View Full Version : Kids Kart Rebuild Roll Bar ->Full Cage

10-02-2011, 10:32 PM
Howdy guys,
Been a while since I've posted, been out playing more than building..:)

Anyhow, I still haven't finished my big buggy build, but got the itch to upgrade the kids kart to a full roll cage. I ordered a torque converter to give it a little more top end. My previous gear ratio was about a 16.8:1 including the jackshaft which made the kart top out at around 10mph. That's all fine for a little while, but the suspension was just soo good, I wanted it to go faster.

The kart overall seems pretty solid, I've even taken it out to the track and ran it pretty much as hard as I could. Eventually I did loose one jackshaft bearing carrier weld while at the dunes last month, hence the desire to rebuild the rear drive a bit.

Anyhow here is an old picture with the kids. Somehow I manage to get myself and both kids in this thing.[smilie=ecstatic.gi: Suspension Yeah I like to drive it too, can't help myself. It's a lot of fun to ride and extremely smooth in even the roughest terrain, suspension really is a bit overkill for the speed, but I'm working on fixing that too..

The problem being there was never a full cage and I didn't like the looks either, so a roof is on the way..:D

And these are the results after unleashing the cutoff wheel and reciprocating saw on the cage. I was a bit hesitant, but it was one of those things where I just had to start the first cut and before I knew it...it was pretty well done.



Out with the old:

Time to build some new..:D

For now I'm going to focus on building the frame, going for a similar look as my bigger buggy build (http://img695.imageshack.us/img695/9633/84563930.jpg) but much more compact in the floor and motor area. Although I'm also pondering some improvements to the rear swingarm. It has too steep an angle which I did to make room for the jackshaft sprockets, but this makes the rear end rise up on load. I'm going to see about lowering it down some and have also considered going independent on the rear too to widen it out a bit. The front is sitting right at 50" wide where the rear is only 46" due to the limited axle width. I've debated about this since there is some stability benefit and simplicity with the solid axle.

We'll see, I already spent enough on the torque converter and cage materials. Hope to at least get the roll cage up and torque converter/new jackshaft rolling by the end of the month when we go to the dunes again.

10-03-2011, 05:18 AM
Good too see you Martin.(if that is your name)

10-03-2011, 01:11 PM
Thanks...yep thats me..:)

We'll see how this torque converter works out. If it's still to slow and the kids are more interested in the quads..I could always throw the KX500 motor in here..that would be a blast in the dunes trails..

10-05-2011, 10:38 PM
Got the main upper hoop bent and tacked into place with a few of the uprights. Starting to look more like a buggy already..:D

10-06-2011, 08:54 AM
Nice to see you back on the site.

10-08-2011, 07:24 PM

Nice to be building again, even if it is on the kart.

Got the roof built and in position, now it's really looking more buggy like..:D



And my tentative to dos:

Glock n Ballz
10-09-2011, 07:26 AM
Good idea.

10-09-2011, 11:49 AM
What about this? Blue...

10-09-2011, 08:55 PM
I like that, I can definitely do the window gusset pieces and some extra area to support the front shocks/a-arms, but I'm holding up a bit on the rear area until I get the new torque converter. I'm going to have to build around the motor, jackshaft, and torque converter.

I did deviate a bit on my hood plan. While I like the triangulation better on my plan, the resulting dash like area was just too far away. I went for something a bit more simple:


And my 8 year old boy for scale. I also lowered the seat mounts and slid them forward a bit. When I sit in there I've got only about 2" of head room. I figured this would give them something they could grow into.

Seat belts have also been ordered and I'm thinking about covering the roof and hood area with black vinyl or maybe some sort of thin plastic. Not sure just yet, but I do need some sort of front tire protection. Perhaps some simple tire mounted fenders or something..

The other thing I'm thinking about is somehow making the pedals adjustable for different drivers foot reach.

I also weighed it today, as pictured above, it's weighing in at 245lbs without the 45lb motor and jackshaft/torque converter bits. I hope it's not getting too heavy for the little 6.5hp motor.

If it is, I'll probably buy one of these and a heavier duty torque converter.
That should make up for the extra weight..:D

10-10-2011, 11:05 AM
Looks good, what engine did you have on there previously?

Would the front shocks work better if you had them more upright or is it just a really heavy spring on them?

10-10-2011, 01:34 PM
double post.

10-10-2011, 02:06 PM
Its a harbor freight 6.5 hp motor. The shock angles worked well for the previous top speed and weight, but I may need to raise them a bit after the weight is added and top speed is about triple the previous amount. The shocks all around are old yamaha blaster shocks I have bought cheap on ebay. The front aarms are from my trx 450 quad and the front spindles are from a yamaha banshee. The rear axel motor plate and steering wheel are the only things left from the original street go kart this originated from. Steering rack is from ebay also. Lots of source variety on this one..:)

10-11-2011, 01:59 PM
Got the Torque Converter in last night and I'm glad I waited on the cage work in the rear. It looks like I am going to have to pull the gas tank off to allow a vertical mount on the pulleys. I am also going to have to do some modifying of the converter mounting plate to run the chain forward as there appears to be some reinforcing ribs that would conflict with the chain. I may add some removable bracing to the aluminum plate too since I will have to weaken it a bit with the mods needed.

Ill post some pics later as I work out the details. I need to have the buggy ready for a dunes trip on the 28th so it will get done soon..:)

10-13-2011, 10:06 PM
Here are a few pictures of the torque converter. Because I'm running the chain forward, I had to mill down the raised portion of the mounting plate.


The cheap little mill drill combo does fine on rough milling work like this.


And this is approximately the motor position. The tank is just sitting there, but it too is going to need some relocation to make room for the torque converter. I am going to redo the support bars for the motor mounting plate and also ordering up a new jackshaft and pillow block bearings since I found that my last one was a bit tweaked when my bearing carrier broke.

I will also plan on adding some reinforcement to the plate at the top to mitigate for the lost plate strength.

10-16-2011, 06:20 PM
A little update, waiting on a new jackshaft, sprockets, and pillow block bearings to finish up the new drive setup, but I'm getting most of the new cage at least tacked.

Deviated from the previous plan some more..:) What plan??





And this is that critcal jackshaft plan. I need the actual pillow block bearings before I can figure out the framing, but the general thought to is frame up a portion of the lower frame with square tubing and bolt through that. I may then lower the swingarm pivot point to match depending on how that layout bit goes.


This should give me just very slightly lower gearing for low speed and almost 3 times higher top end. I'll see how this motor carries the weight, if need be I'll go to a 16HP motor and 500 series comet. I just don't want to spend the money until at least trying this.

10-16-2011, 07:22 PM
I wouldn't get a new motor , if you take the governor off the motor you will be able to rev it to about 5,500 rpm instead of the luggy 2,500 that the engines are limited to , I've got a brigs 5 horse on one of my builds with the governor removed and it will go 40 [smilie=ecstatic.gi: and still drifts in the dirt. the engine might wear a little faster but running a higher quality oil will help a lot.

10-16-2011, 07:29 PM
Just looking over the your pictures again if you do remove the governor you probably wouldn't want to set the rps not too high ,I didn't see that it was a overhead valve engine if you rev them too the valves can jump and hit the piston which can result in breaking the valve. But 4,000 would probably still be safe. [smilie=jumping.gif]

10-16-2011, 10:00 PM
I'm hoping to have this done so I can give it a try at the dunes on the 28th. I'm sure you're right, I should probably focus on a few minor engine mods before trading up. I just can't help but want to drive it myself and more power always sounds good in the sand..:)

We'll see, I did take it out before in the sand and putted around with my friends 4 year old with little 18" paddles when it was a kart. It did ok then and I haven't added all that much more weight with the thin walled tubing.

10-23-2011, 04:50 PM
Well, I got it to at least drive-able although it seems the gearing is a touch too tall, but not bad. A definite improvement with the torque converter. I may play around with the spring positioning too, it seems to up shift at slightly lower RPMs than optimal for the engine HP.

I built the jackshaft framing with square tubing, installed the pillow blocks with 1/2" bolts this time and lowered the swingarm pivot point to match. I did have to mill a bit more of the torque converter plate to get chain clearance. I also fabricated some mounts to move the tank over and also added a lateral brace to the torque converter plate, it seems very solid now.

I may change the 12T sproket to a 10T, we will see...I just think the top end is a bit too fast for what I want and a little shorter gearing would probably help on reducing belt wear.

Still some welding to do and need to make some sprocket/chain guards as well as install the seat belts.


My co pilots..:)



10-25-2011, 10:53 PM
Finally got a chance to run up to the hill and take it for a little spin near the gravel pit, and made a video to walk you through a bit of the history, show the suspension, and a little action.


Kids Go Kart Rebuild - YouTube (http://www.youtube.com/watch?v=7yUddgHhku0)

10-26-2011, 07:45 AM
suspension on that is great!! good job... it looks like a lot of fun.

Glock n Ballz
10-26-2011, 08:06 AM
Oh man thats great! Good job. I bet your kid is stoked!!
Good Dad!

10-27-2011, 08:45 AM
Thanks guys!

Going to experiment a bit with moving the spring position on the driven pulley. I got it switched to max tension now which should hopefully allow the engine RPM to go up a touch. It's not much fun trying to keep that drive clutch together while fighting the spring and e-clip all at once..whew. I did it with the driven pulley removed, but I think next time 'll leave it on the keyed shaft to at least give me one more hand..:)

It looks like if you really wanted to you could even drill a few more spring position holes to maybe get even more tension.

Heading to the dunes for the weekend...mostly an adult 450 quad trip this time, but here are a few more pictures of the torque converter/jackshaft setup and why I had to mill down part of the converter plate. You can also see the lateral brace I added to the top of the plate to mitigate the slight weakening. Also note that the swingarm pivot and jackshaft pivot are in line so no chain tension variance with swingarm movement..:)




I'm generally very happy with the buggy now other than seeking a bit more power out of the motor. It is fine on dirt and more than enough for the kids, but it's probably a bit underpowered for sand. I figured I'll try to tweak the motor/torque converter a while and if I'm still not happy look to upgrading to a 16HP and comet 500 series toque converter later.

10-27-2011, 11:34 AM
Great job! You're kids are very luck. That red go-kart at the begining of the video looks exactly like the very first go-kart my grandparents bought me.

11-06-2011, 11:10 AM
Little update, decided on two things. One to get some paint on it to protect what is done with winter moisture setting in. Just a rattle can Rustoleum blue... I know I'll be doing some more cutting/welding for the new motor upgrade, but a little touch up is better than letting the rest of it rust.

And the second was to order the motor upgrade, it is a clone (Duromax) 16HP with electric star (http://www.ebay.com/itm/DUROMAX-16-HP-GAS-ENGINE-GO-CART-MOTOR-LOG-SPLITTER-/120803348110?pt=LH_DefaultDomain_0&hash=item1c2070ce8e#ht_4993wt_1396)t. I was going to buy one of the Lifan home depot 420s without electric start (which is cheaper), but they were all sold out. My son also said he really wanted electric start so he could start it and have lights....so I figured why not...maybe I can even add an electric horn and a few "fun gagets" for the kids to play with. I can also probably wire up the ignition switch to the dash to give it more of that "Starting a car" feel.


I haven't bought a new torque converter yet, that may have to wait for next month...spent enough on the motor this round. I'm considering comet 40 and 500 series. I'd prefer the 500, but I may have a source for a 40 series for relatively cheap. Still working on that.

The 6.5 actually does fine for the dirt, I just wanted to have a bit more power for the sand.

11-06-2011, 03:22 PM
Nice job man. I hope to start on my sons here very soon. I got all the parts ready to go. But he just turned 2. Maybe for his 3rd

You did a fine job of making a baby mini out of a yard cart. Top notch

11-07-2011, 08:09 AM
turning out really sharp with the blue(my fav color). quick question about the cvt... instead of buying a new one, can't you just upgrade your current to fit the new engine? (i'm new to CVT's)

11-07-2011, 06:47 PM
Nice job man. I hope to start on my sons here very soon. I got all the parts ready to go. But he just turned 2. Maybe for his 3rd

You did a fine job of making a baby mini out of a yard cart. Top notch

Thanks! It's kind of hard keeping up with growth and making a setup fit different leg sizes. For a while there I had two sets of pedals on the kart, one just big enough for my kids and a longer reach set for myself which eventually my son grew into also. My only suggestion is to make it big enough for you to barely fit and be ready to move the pedals around as needed.

turning out really sharp with the blue(my fav color). quick question about the cvt... instead of buying a new one, can't you just upgrade your current to fit the new engine? (i'm new to CVT's)


The standard Comet 30 CVT comes with a 3/4" driver(primary), so when upgrading to the 16HP motor, I ended up also upsizing the motor drive shaft to 1". You can buy a 1" comet 30 primary, but that would be another $75 and is likely not going to work very well. I have seen and heard of people using motors with up to 8-13 HP with enough gear reduction and flat terrain, but the comet 30 is actually only rated to 8HP.

Because I'm going with 16HP and plan to abuse the clutch in the dunes, I figured I'd go through belts like crazy. I have even heard of some people modifying the 6.5HP motors and tearing up belts.

So...while it could be done by buying a 1" bore comet 30 driver, I decided I better save the $75 and buy a heavier duty clutch. A comet 40 would work, but it's a symmetrical belt type and requires both drive and driven pulleys. You can run across those for around $200 for the pair used on ebay, or you can buy a comet 500 series for around $300. I'm leaning toward the comet 500 because of the larger belt (more beefy) and much larger gear ratio (about 3.5 variation vs the comet 40 2.5). The larger ratio will allow me to have a lower low gear and higher top speed over the comet 40.

I'm also looking at comet 94C and some sled clutches which you can find driven units for pretty cheap. The problem is figuring out the compatibility between units and tuning it for a low RPM 4 stroke vs. the factory high rpm 2 stroke they are setup for. You can find parts for the 94C, but there isn't much info on the driven units other than driven FL250 units, but that's all high RPM again.

Anyhow, I've been shopping around quite a bit and still haven't decided what to get regarding clutch, I'm just pretty sure the comet 30 wouldn't be up to the 16hp and sand dunes/hills.

11-08-2011, 04:43 AM
Have you talked to QDS yet?

11-08-2011, 01:22 PM
No, but I did go ahead and make an order through bmikarts. They did pretty well on my last order, so I gave them a try again. They had the comet 500 in stock for around $340 for everything and also carry the other bits I needed like 3/4" jackshaft and keystock. I went with the 500 because it's much more compact than a sled secondary and I can order springs and weights for it still. I' m not thinking I will do too much for mods on this motor and the 500 is rated for 16hp. It was more $ than I wanted to spend but I think its worth it.

Now I'm just waiting for parts to ship..:)

11-10-2011, 11:55 PM
Got the new clone 420 "Duromax 16HP" motor in. I believe the 420's are simply a larger bore and stroke of the GX390 clones. This one does seem to have some enviro friendly features, but generally pretty well done. It is definitely a bit bigger in overall dimension than I had visualized, so I'm guessing it'll mean more hacking of the rear.

Anyhow, nothing like a good motor unboxing..:D








Not quite sure what the little exhaust T feature is, but it reminds me of streetbike PAIR's system, probably allows some air into the exhaust stream to improve emissions is my guess since it really doesn't have any other feed or connector and too far to be any sort of cat type thing.

The gas cap is a much improved version over the little 6.5 clone though, this one actually looks like it'll hold gas without spilling everywhere...even comes with the chain. It also has a vent that leads back to the carb.

The air filter however seems pretty restrictive and the muffler is pretty big too. I'll have to see how the jackshaft and comet 500 driven all fit before deciding what has to be moved around.

The electric start wiring and pod comes separate which I'll probably keep that way and simply extend the pod up to the dash for key start...kids will love that. Even comes with batter terminals and cables which is pretty cool I thought.

Going to take a few step back in completness with this motor upgrade, but I like the beefyness and quality so far. Much improved over the prior 6.5.

11-11-2011, 12:59 AM
I cant see any photos just a frog in an iceblock?

11-11-2011, 10:26 AM
I cant see any photos just a frog in an iceblock?

Hmmm...the picture server must have been swamped. Are they still not showing up?

11-11-2011, 01:07 PM
not sure about a frog and an iceblock... but, i see the pictures just fine. the battery connectors are a nice touch. The electric start 6.5 i ordered didn't come with them.

11-11-2011, 01:32 PM
Yea the Y takes fumes back to the head. Nice little engine you got there bro. That should wake it up

11-11-2011, 04:28 PM
After cutting off the old mounting plate and supports.




I could use this spun 3 gallon tank if I wanted...looks cool.

And a mockup. One big advantage of the 500 series is the low range ratio it gives, I'll probably try to do something like this and simplify to just one jackshaft. I will have to build some pulley protection below, but it'll only hang down a couple of inches below.


Some theoretical speed calcs, this should have a lower low range than the 6.5 motor had with torque converter and higher too. I'm assuming I could dial up the governor to 4200 RPM, but I'm not sure yet.

I ordered an 8" belt, but I might actually need a 7" now that I'm test fitting.

And the 500 factory comes with the red highlighted parts, I may buy some purple springs and test out a higher RPM. Looks like I can get just about any of them here:

Here is a stock GX390 HP/Torque curve

Not sure I believe it, but the 420 specs are 16hp peak and 21ft-lbs of Torque peak

11-12-2011, 05:06 AM
I see your power curves but only frogs for other pics..hmmm must have to subscribe to a frog site??

11-12-2011, 09:55 AM
I see your power curves but only frogs for other pics..hmmm must have to subscribe to a frog site??

OK, I can see it using my phone and other computers, so it must be an imageshak thing with certain locations.

Here is the photo album, maybe that will work?
Photo Album (http://profile.imageshack.us/user/eightyeighthuny)

11-12-2011, 10:11 PM
Decided I didn't like the box air filter system, so I went down to my local autozone and found a 3" pod k&n style filter for $19. Bought a 3" pipe piece for $2 and started fabricating. I made the filter adapter using a piece of scrape 1/8" steel plate and welded the pipe flange piece. Then I welded in a hose nipple to capture the valve breather too and finally made a cone taper out of a piece of acetal I had to give it a nice velocity stack taper transition. I used my mini lathe quite a bit and the mill to create the nut seats. Took a while, but I like it. I may buy some 3" elbow and additional tube to extend the intake up just above the back of the seats for cleaner/colder air flow.

A little overkill being 3", but why not..:D

Tried to upload the pictures to the site attachment tool, but even when reduced to 600 pixels and well below the 512K, I'm not able to add a .jpg:confused:

Imageshak works for me though, at least I can see them ok.




That should make it breathe better...:)

11-13-2011, 07:09 PM
Without the clutch here, I decided I'd do some mockups with sketchup. Of coarse it's way too easy to keep going and I decided to pencil out what independent rear would look like..:)

Possible future upgrade..:D

It's currently 46" wide, this would widen out to 52"






The red would be the new motor framing using square for the bottom bolt through parts, green would be the trailing arms.

11-13-2011, 07:43 PM
Thats the Martin we know and love!I was waitin' for some sketchup modeling!

How did you model the engine so fast or did you get it from somewhere?

Very cool.

11-13-2011, 07:55 PM

I got lucky and found a 6.5HP motor model from the 3D Warehouse, I downloaded the motor, the pillow block bearing, the shocks, brakes, and the sprockets and simply scaled them to approximate scale. It's not perfect, but fun to play with and at least give you the general idea. It's a lot easy and cheaper cut/deleting in sketchup than in the garage.

11-13-2011, 09:33 PM
Very cool, what is the final gearing with that model? From previous experience your going to need a second jack shaft or run over sized rear sprockets. I put one together a long wile back with a solid rear it would fly but the belt would smoke just to get it rolling.http://home.comcast.net/%7Efasterpatrick/wsb/media/355398/site1020.jpg I wound up using the second shaft as the pivot for the swing arm and ran the brake there as well geared it 2;1 off the driven pulley and 2:1 off the Jack shaft made for plenty of clearance. The use of solid modeling sure would have saved me lots of headaches back then.

11-14-2011, 12:12 AM

I've been thinking about a double jackshaft option too. I'm running really small 18" rear tires at the moment, but considering swapping out to some 20" atv rears I have handy. My wifes LTR450 rarely sees dirt, so her tires could be used easy enough and help with some ground clearance issues I've had with the 18" tires.

My current gearing is 12T front to 60T rear + 12:14Jackshaft +1: 2.68 comet 30 torque converter for old 6.5 setup, but I'm not sure what will be ideal for the new 500 series comet. It's supposed to get down to a 3.41 ratio where the comet 40 gets to 2.5. When I had a jackshaft only on the 6.5, I was running around a 18:1 total reduction, so somewhere between 16 to 20:1 should be more than good for the 18" tires...it's just that I'm not sure about what I'm going to do for sure on tires. As the buggy progressively improves in speed/power/handling...it seems ground clearance and suspension travel demands increase as well, so it's probably safer to go with the second jackshaft idea to allow flexibility in increased tire size and smaller final sprocket.

This was my idea for a second jackshaft, which could work out as well... just more work and another chain to maintain. If nothing else on the independent rear idea, it would really help in reducing that rear sprocket size and also help in general with ground clearance. I could probably go down to something like a 20T 40 series rear instead of the 60T I currently have on the solid axle. Maybe a 28T on the jackshaft with 10T sprockets all around and 20" tires.




11-14-2011, 08:02 AM
Step up your final drive chain to #50 and run your brake on the jack shaft. Simplifies the rear brake system. Yes the snowball effect has started, you may need to get it finnished before it gets to far out of control.

11-14-2011, 10:49 AM
Your sketchup skills are very impressive!

11-15-2011, 12:56 PM
Your new design looks very familiar:





I am in the process of changing my rear drive to use a Polaris transmission and CVs. I will have all my rear drive parts for sale soon if you are interested. The major challenge with this design is keeping the chains aligned and tension just right. I ride in really rough terrain and sometimes you just can't get those bearing carriers tightened down enough to prevent a little movement.

11-15-2011, 08:45 PM
Thanks..yeah the shredder is a big inspiration for it although Ill be making my own trailing arms so I can get that lower shock mounting point down lower for more spring rate progression. I would be interested in the hubs and maybe the sprockets though.

11-18-2011, 07:12 PM
Minor update, got my new comet 500 clutch drive/driven/belt and a 3/4" jackshaft.




The drive clutch sticks out a lot more than I expected so I'm actually shifting the motor centerline to the right a couple of inches so I have a bit more room to make chain clearance. I'm also going to basically rebuilt the swingarm to fit the new motor clearances.

For now I'm going with the existing solid axel I have on hand, later I may give the independent thing a try, but it'll take some more parts and planning there. This will simplify the number of jackshafts and keep CG down low too AND give me a chance to play with the gearing a little. I will have to build some sort of secondary guard below the pulley too, but it only hangs below the frame a couple of inches at most.

11-19-2011, 05:38 AM
a cheap irs for a small buggy like that is an older polaris 400 front diff and axles. Cuy the hub side off the axle and weld in your stub. You could even potentialy use a polaris sportsman rear up right, hub and axles with the front spool. Then you just gotta un bolt the polaris sproket and add what you need

94 POLARIS SPORTSMAN 400 FRONT AXLE DIFF CARRIER | eBay (http://www.ebay.com/itm/94-POLARIS-SPORTSMAN-400-FRONT-AXLE-DIFF-CARRIER-/110763524726?pt=Motors_ATV_Parts_Accessories&vxp=mtr&hash=item19ca054276)

Or if you wanted a ton of work you could turn the engine side ways and add a sproket to this style diff

03 Polaris Sportsman 500 H/O front differential / diff | eBay (http://www.ebay.com/itm/03-Polaris-Sportsman-500-H-O-front-differential-diff-/140642111900?pt=Motors_ATV_Parts_Accessories&vxp=mtr&hash=item20beec519c)

When I build my sons I will either do a linked solid rear like a TK or the polaris diff most likely.

11-21-2011, 11:42 PM
Thanks, I may do that for my bigger buggy, but I'm pretty sure I'm going to keep the kart chain driven for the time being anyway.

A little update, spent most of the last weekend getting the motor mounting and jackshaft bolts dialed in for the 8" CD comet spacing and started in on reconstructing the swingarm to fit the motor. I pretty much cut away the entire swingarm except the bearing and brake mounts and starting building out from there. I did squeeze out every bit of travel possible before the axle impacts the motor by finding that high point and extending the arm length to that point. That made the swingarm about 2" longer than previous which shouldn't affect maneuverability too much. It's good for about 10" worth of travel in the rear if I can get that out of the shock travel,leverage ratios and ride height I'm playing with.

I am also experimenting with new shocks and will probably go with two TRX450R rear shocks as they seem to provide the best dampening control. I had a set of front 400EX front shocks that looked good (one on the left in the pictures), but there is litterally no dampening left in these so that was a waste. The 450 rear shocks are actually pretty reasonable costing around $50 used on ebay and do provide dampening control.

I also bought some of that "Pimp my ride" 3" custom air intake tubing to bring the intake out of the dust, but admittedly it looks a little big blingy for my taste. I may flat black the intake tube to tone that down later.




There is more swingarm building and rear engine cage building to do, but it's a good start and it's a roller again..:D

Thinking of sticking to the solid swing for now and maybe ordering just a wider solid rear axle + hubs. Maybe not quite the smooth ride of independent, but that would make for a very stable ride and reduce roll over risk. That and it's simple which is always a bonus..

Going well, but that bigger motor does weigh quite a bit more adding probably another 30-45 lbs.

11-22-2011, 08:29 AM
bling isn't my thing either... but, i think that air intake looks good chromed. :D quick question: what size tubing did you use for the frame? (went back and read the thread but didn't see it)

11-22-2011, 09:09 AM
Thanks. Most of it is 3/4" ID thin walled with some full weight pipe in areas that I felt were suspect to regular rock damage. I also used 1/2" thin walled for webbing. Then I used 1" heavy walled square tubing for motor and jackshaft mounts. Overall it's very light weight for the frame. The motor, and drive train and suspension is what account for most of the overall weight which is all sitting low in the frame. Need to weigh it again..but overall probably looking at around 350-400 lbs total.

11-22-2011, 02:17 PM
Looking good. Is your driven clutch going to clear the frame when it opens up at higher rpm? It looks pretty tight in there.

11-22-2011, 06:23 PM
I weighed the buggy as it sits without seats or gas tank and I'm currently at

Front = 117lbs
Rear = 195lbs
Total = 312 lbs 62% rear biased without rider. Rider weight would probably make that bias a bit more to the rear.

So by the time I add a battery, gas tank, oil, bench seat, lights and misc goodies, I'll probably be pretty close to that 350lb mark which I guess is pretty good considering most of the 250cc type sized two seater off brand buggies are rolling at the 500lb and higher range.

I also just checked that secondary clutch. The picture is a bit hard to see, but I have about 7/8" of space to open which should be just barely enough, but it is a good point and I may have to do a little expansion there.

11-22-2011, 06:49 PM
Cant wait to see this run,please take a vid if you can.

11-22-2011, 07:48 PM
I like your buggy, but are you worried at all about the driven clutch being kinda low for getting into junk and water?

11-27-2011, 07:10 PM
I will make a vid, but I'm still working out the details. I also plan to make several guards particularly for that secondary pulley. I want something to resist both dirt/mud as well as taking a rock hit from below so it will be beefy. I'm thinking something like 4x1" heavy channel cut etc. I also need to make some guards to separate the cockpit area from curious fingers..etc.

In the mean time here is another update. Been working pretty regularly in the evenings and got to take it for a quick front yard/neighborhood spin this evening.

Been working on a lot of details like the lower shock mounts. I cut out the eyelets from my 400ex shocks which had needle bearings and seals that were a perfect match for the 450R rear shock bottoms and I built that into the swingarm..came out really nice. Also working on beefing up the upper shock mounts, got the right side done, just need to mirror the left. The rear suspension is a huge improvement and I can tell immediately when driving it too, so nice and plush in the rear now with ample dampening control.

Other details like the throttle linkage take time too, here I fabricated the cable mount, and modified the factory throttle arm to retain the govenor for now with various bits. Throttle works well in testing too although it does seem to peak in RPM a bit lower than I'd like yet (a little tweaking in order still).

Here is that new shock position. You can't see the lower mount, but it's built in with nice needle bearings.

And a bit rough and tacked only, but here is an automatic chain tension-er idea I was working on. It only took a few minutes to realize I needed to limit the throw minimum or the two sprockets hit on decel. Needs more testing and welding, but this might help minimize chain maintenance.


For temporary use, I've got the factory ignition box mounted behind the wheel to access the ignition and circuit breaker. Wiring the unit did take some trial and error since there were not any instruction. I assumed one loose eyelet wire would go to ground when that was actually intended to be powered +12V. After figuring that out, all went fine in getting the motor to turn over and turn off. I also bypassed the low oil shutoff since I quickly learned that didn't work for the previous motor (hard rights would kill the motor).

I don't have a choke cable setup yet, but the ignition switch is at least up in the dash.



And a downward look at the clutch and chain, a tight fit, but it all seems to be working ok.

And while it's not done yet, here are some overall pictures since I had it outside tearing up the front yard..:D




Going in for knee surgery this week, so I'm not sure on timing of my next update and actual offroad ride/video. Regardless, I was happy to hear the motor run and at least take it for a quicky spin today. Getting there...and getting better little by little:D

The rear suspension update was a huge improvement. Now the buggy droops on the rear with it's own weight and the dampening is many times better. The clutch is also much smoother and more refined than the comet 30. The power gain is definitely there and the large ration on the clutch also make for some nice smooth acceleration. It does seem to have both a lower low speed and higher top speed.

On the "To Dos"

-Rear engine removable guard
-Intake Support
-Possibly 450 silencer/custom exhaust
-Clutch/Sprocket Guards
-Shock Gussets
-Seatbelt mounts
-Battery box
-Vinyl or PVC Top/Hood/Sides Skin?
-Choke Cable

11-28-2011, 02:48 PM
Really nice work! Good luck with your surgery.

01-08-2012, 08:22 PM
I really like this build, you have a good thing going. cant wait to see the video.

01-10-2012, 11:44 PM
Been getting my knee better and almost have range of motion back now to where I can fit in the little beast. By the end of the month I should be back to continuing with the build and be able to fit in for a test ride video of sorts.

01-12-2012, 08:08 AM
nice cart man...

04-21-2012, 08:50 AM
Been away a while with the knee surgery and cold weather, but the sun is back out and my knee is much better.

Took the boy out for a little spin yesterday to test out the 16HP motor. I had no problems at all until I wacked a 2' boulder while trying to make this video..

2012-04-20_KidsBuggyTesting.mp4 - YouTube (http://www.youtube.com/watch?v=ueiPLEYQK8g)
You'll see it at the end, when I got home there was a 3" gash in the left front tire. Whoops!

And a few pictures:


Near perfect fit for my 8 year old boy..

And even though I'm way too big and heavy... I don't mind a little playing either...:D

04-21-2012, 11:42 AM
Awsome build, simplistic... sorta and yet looks like a real kick in the pants.

04-21-2012, 04:08 PM
Stopped by our tire store and sure enough the 3" tear in the sidewall was too much for repair. New tire on order.

I'm surprised the direct rock hit like that didn't do some front end damage, but I can't see anything else wrong. I'll probably double check toe in/out when the new tire arrives anyway just to be sure.

It's a fun little buggy to ride, just need some rock protection to the clutch secondary and sprocket then some skin..:)

04-21-2012, 07:35 PM
Very cool Martin,lucky kid for sure.

04-21-2012, 08:53 PM
looks like a lot of fun... you're son is very lucky!

04-23-2012, 02:43 PM
looks good, you guys should have some fun with that

04-23-2012, 09:36 PM
Looking forward to this summer at the dunes with all the kids piling in there. They are going to have a blast.

Started working on the body panels. I found some fiberglass reinforced panel material for pretty cheap that I'm going to try.

This is a photoshop concept of what I was thinking for panels...

And here is the actual panel work done so far..

Still missing that rock video left tire getting replaced...:)

08-13-2012, 08:12 PM
A little update on the kids kart. I took it out a couple of times over the last month which inspired me to finish up the finer details I've been needing to do including:

-Adding seatbelts 3ea
-Building secondary clutch guard
-Building battery box
-Finish building upper rear shock mounts
-Modifying automatic chain adjust to remove primary clutch contact.
-Building clutch/battery/sprocket interior cover panel to keep those fingers and seatbelts from wandering into bad places.
-Finishing rear engine hoop bracing for front to back roll over protection.
-Modifying Intake tube to remove rear disc conflict, raise to minimize dust, permanent mount.
-Add side and front side panels to protect from front tire debris and keep legs and toes inside where they belong.
-Reroute and rebuild exhaust header.

And a few little odds and ends. Spent the better part of the last couple of weeks doing this and it's turned out really well. I found that putting a ziptie on the governor spring is a quick bypass and really livens up the motor. With the govenor in place it runs plenty good up hills and around for the kids, but removed is actually a lot of fun for me to ride...it will actually turn the tires taking off on concrete a bit and feels like it has quite a bit more power and torque than my sons 250ex.

I'll post a few pics in a bit.

08-13-2012, 08:19 PM

Back seat panel and clutch/battery/sprocket panels removed
Secondary clutch guard made out of heavy angle iron since it hangs down a little lower than the rest of the frame.
My little home brew battery box is a perfect fit for the little micro battery that I had on hand. I was a little worried the little battery wouldn't have enough cranking amps, but it works perfect and has for many outings...never had to use the backup pull start yet. Mount is solid, no movement at all.
My battery/clutch/sprocket cover panel to keep the fingers and belts separated from the moving parts. Simple, and works well.
New exhaust header, rear upper shock mounts, and intake mounts.

About all that's a must do left is an exhaust heat guard/shield, flag mounts and the rest will be little electrical toys like lights and maybe a horn.

Pretty happy, the little buggy has been a blast to ride on the 50" and under trails. It is exactly 50" wide up front weighs around 400lb and has about 10" of travel in the rear and 8-9" up front. I took the kids through the trails rather aggressively and honestly have more fun than riding my TRX450R..something about the low CG and railing corners while being low to the ground that makes it just fun. The rear TRX450 shocks are also easy to dial in compression/rebound on and ride extremely smooth. I'm most amazed at how smooth the ride it, it soaks up whoops and bumps better than any quad I've ridden...very smooth..:) The kids should have fun with it at the dunes this summer too as both plus a friend could pile in there (govenor adjusted) and tool around camp safely seat belted and caged...I can actually ride in there snugly with both kids at either side...:)

Oh and kind of a side note, but I already got pulled over by the ATV police in this buggy. I think the guy just wanted to check it out, but he said he couldn't see my ATV sticker which is stuck to the top of the tank. He said he wasn't sure what class this fits in if it's class 1 (ATV) or 4 (SIDE BY SIDE). I told him it was under 800lbs and under 50" wide, so it should be a class 1 and he kind of agreed. A class 4 would technically need seatbelts and a fire extinquisher which I didn't have installed at the time of pursuit. It was pretty funny actually, I was tooling along a designated 50" and under trail when the red and blue lights and siren went off behind me. I had never actually seen an ATV equipped with lights like that and was baffled by the siren not knowing where it was coming from. He let me go after seeing my sticker was good, so all was well..:)

One last front picture, sort of has that raptor look, maybe I should sink in a few lights in those bare triangles and make some black panels there or something for fun.

08-13-2012, 08:53 PM
Nice to hear a good police story. Cool little buggy.

08-13-2012, 10:01 PM

I do have an electrical question if anyone knows. The ignition switch basically sends a ground to the coil circuit when the key is "OFF". I was wondering if there was any way to use this ground output to allow lights to be on when the key is "on".

I know a basic relay can convert the grounding output to positive, but is there any way to make the absence of ground become the trigger for power on? I'd like to wire some headlights to come on with the ignition, but knowing the kids would like it make it automated so there is no accidental leaving of the lights on.

08-14-2012, 10:13 AM
Really an awesome build. I'd like to make a similar one here to replace the Chinese death trap my wife and daughter currently drive around camp. Congrats !

08-14-2012, 03:09 PM
Nice work Martin! I'm sure you've made the kids really happy. Once my two girls are older I'll probably build something similar for them.

08-14-2012, 03:18 PM
Martinm thats a cool lookin buggy from what I can see very well built and thought out . What are ya buckin for Dad of the year. LOL [smilie=haha2.gif]

08-14-2012, 09:36 PM
The buggy has fulfilled many purposes for us. For me it was a learning tool, for my kids it has been a fun toy we can all ride in together. It's kind of hard to believe that it started out as a suspension-less manco type single wheel drive street go kart that transformed over many rebuilds, but I has come a long way now. It's now been through about 3 different front suspension rebuilds, two frame rebuilds, and two motor/drive system rebuilds.

I like driving this little machine. I'm seriously thinking my 3rd build might be another 50" compatible of similar size...I'm impressed with how fun the smaller size is once you get a little motor behind it and the size is nice for hauling. I wouldn't mind doing one more micro 50" wide with something like a 450 motor and a touch more suspension...now that would be a ton of fun in the woods.:D

08-14-2012, 10:57 PM
Martin, You have done an amazing job on this buggy, both this one and the one you are working on are some of my favorite buggies I have seen so far!

I know a basic relay can convert the grounding output to positive, but is there any way to make the absence of ground become the trigger for power on? I'd like to wire some headlights to come on with the ignition, but knowing the kids would like it make it automated so there is no accidental leaving of the lights on.

I believe what you want is a DPDT switch (Double Pole Double Throw). This switch controls two independent circuits at the same time (Dual Pole). The switch also allows each circuit to be connected to one of two on positions (double throw). Here is a picture to aid my crappy explanation :D,

To wire the switch (assuming terminals are in standard layout), using the picture below as a guide:

-Connect A to your frame ground.
-Connect F to your battery positive.
-Connect D to your headlight positive.
-Connect C to your magneto ground wire from the engine.
-Do not connect terminals B, and E to anything.


Note that the wiring arrangement I explained is just one way of doing it. Make sure your switch does not have an off position in the middle, and that it can handle the wattage of the lights. Do you know how much power the charging coil puts out? Hope that helps.

Thanks, Rory

08-15-2012, 01:59 PM
Awesome, thanks a bunch for taking the time. I'm not sure on the coil limits but I'll see what I can figure out...:)

09-02-2012, 09:46 AM
Little update.
I took the kids buggy out on our last camp trip and it was a lot of fun, but I never liked the smaller back tires and narrow 46" rear width when the front was 50". I ordered a new 45" solid 1" rear kart axle, heavy duty 4 on 4 hubs, spare belt, and some misc. I old hubs were an odd 3 on 100mm pattern and I wanted the rear to be honda 4 on 110 so I could use some spare rear tires from one of our three honda/suzuki quads.

The hubs were not very true, so I faced them on the lathe and drilled out the 4 on 110 studs in, they came out pretty good and heavy duty.

I can adjust the width with the new wider axle from about 48-53" in width and currently set it at 50".

Very solid and stable now, I think you could darn near get it sideways on pavement and still not roll it. I also changed out the front sprocket from 10T to 9T to maintain the gearing I previously had and liked. I tried the 10T for a quick spin and it was pretty good, but for sand and paddles, I didn't want to stress the belt anymore than I had to, so I went with the 9T front for lower gearing.

The only issue I have now is the rear brakes are now a bit soft for my liking due to the larger rear tire size. I have an old GSXR600 rear caliper I may use to replace the offbrand atv caliper I currently have on there. I could also add calipers to the front if I really wanted to. I also need to run a choke cable to the dash area to avoid having to reach back for the choke to start.

Just trying to get this little buggy solid for our dunes trip at the end of the month, getting there. I also picked up a pair of 20x12x10 dune slider paddle tires for the rear off craigslist for $40.

I'm really impressed with this 16HP motor after bypassing the govenor, opening up the intake/exhaust, and rejetting...it's a fun machine to drive around even for us BIG kids..:D

09-03-2012, 12:41 PM
That is very cool wish i had a dad that could do that when i was growing up!!!! But from what i hear is dad drives it more then kids LOL[smilie=ecstatic.gi: im sure you are just TESTING IT and making SURE ITS SAFE! But great job

09-03-2012, 07:04 PM
LOL! Always wanted a go kart when I was a kid. Just don't tell my wife and kids that this 37 year old kid is finally satisfying that need..:D

Anyhow, I have made some minor progress. Got a dash mounted choke cable hooked up and that works good. Also got the GSXR600 rear caliper mounted and despite the larger pistons, the rear disk brakes alone still seem a bit soft. I thought it was maybe just not enough master cylinder throw, but after some testing in the neighborhood, the rear disc and pads were actually smoking hot.:eek:

The rear brakes work, but just didn't want to lock up the rear on pavement like I had hoped they would.

I guess it's time to get those front brakes mounted up...more work!

09-04-2012, 04:13 AM
that should make big differance for stopping what kind of Mc you using? for the rear? think pads would still smoke as they are in contact with disks and just because they are red hot doesnt mean they are clamping hard enough just like driving with foot on brakes

09-04-2012, 07:13 AM
It's an off brand atv master cylinder, so not a quality unit and possibly the problem. Seems like I just can't get enough volume out of the throw. I changed the caliper and adjusted my pedal leverage but still not satisfied. Seems like I get full pump but it is just not enough to lock up stop. I am thinking I might buy a larger Wilwood and rebuild the pedal system. Is a 3/4" master enough to run two atv and one streetbike calipers or should I go with 7/8" or 1"?

A proportioning valve might be in order later too, but for now I was just thinking of hooking them all up together.

I also have the gsxr rear MC that came with the rear caliper, but it is only 1/2" and I figured it isn't enough to run front and rear calipers with?

Brakes are just one of those things I want perfect and more than plenty of stopping power and I'm not there yet.

09-04-2012, 09:09 AM
go through the threads here i looked at one last winter on brakes for same reason im running suby discs and calipers so i need way more then
mc master. Do you have just one disk on rear? then i would think a 3/4 or even a cycle MC should work for that one brakes are very funny too much MC and pedal very hard not big enough and well you know. some of the other guys here could answer better than me i will look around also and see what i come up with even the guys that sell MC should be able to help or someone from summit racing or jegs or even willwood good luck

09-04-2012, 12:43 PM
Thanks! I just have a single disc in the rear. I'll do some searching and reading, but I'm sure its a bit of a guess unless the caliper volumes were all known in detail and even then probably have to trial and error the pedal leverage some. Utilizing the front discs already in place should help though and figuring this out on this build will help my planning for my bigger build too. I find it is cheaper to make my mistakes on the kart...lol.:)

09-04-2012, 01:43 PM
After digging through all the threads, I decided on a 3/4" single cylinder for this kart build to share between all three calipers. Somone ran a 5/8" with a similar set and while it worked they though a 3/4" would be preferred. Stopped by my local autoparts store and ordered me up one..should be here tomorrow...now for hoses and adapters and Tee fittings. Master is 3/8-24 out and all the calipers are 10mm banjo fittings. Hope this all works in the end..:)

09-05-2012, 01:23 PM
Im sure it will. good luck hope to see vid of it in near future

09-05-2012, 02:27 PM
alittle late, but i was researching the same awhile ago and 3/4 is what i ran across as the preferred size. :D

09-05-2012, 08:19 PM
I know I am late. Get a master from a neon. Single res and four ports

09-05-2012, 08:55 PM
Thanks. I tinkered around a bit more with the old master/pedal setup and it's just not enough volume for the new GSXR600 rear caliper.

I got my new 3/4" Master in at my local auto parts store. I just looked through a catalog of automotive masters and found this one that was 3/4" with a simple tube reservoir. Seems like a nice quality unit in comparison to the atv stuff, has a nice ball joint and what seems like an internal valve. It has over an inch of travel too, so I'm pretty sure it should be more than enough volume to handle the GSXR rear caliper and banshee front calipers.

It's a bit bigger than I imagined, but I think I have an idea on a mount. I'm going to mount it between the front arms with bottom hinge pedal and push rod just below the steering rack.

Now I just need to figure out my lines/adapters/hoses and fabricate the mount and new pedal. I have some banjo to metric flare hoses from the banshee for the front and banjo to banjo hose for the rear, but a mixture of SAE and metric threading. The master cylinder is 3/8"-24 out.

Here are a couple of pictures of the rear caliper upgrade and new Master I just picked up. The rear caliper is all installed. I also have banshee spindles and disks already in place up front so all I have to do there is mount up the calipers and hoses.


09-06-2012, 03:58 AM
nice mind me asking how much that master was and where you bought it maybe a part number?

09-06-2012, 07:53 AM
Sure, I paid $52 for it. I found it in a Raybestos catalog under a different number by picture, but they didn't have any in stock and ordered under a different rebrand BEC072-2660. I bought it at Novak's auto parts here in town 541-884-7749. I order a lot of my stuff on ebay but these guys are nice local auto parts folks I like too. Maybe that part number or a raybestos catalog is available in you area you can peruse. It was one of the few 3/4" masters I could find in there. If I couldn't find one there I was going to order a Wilwood on ebay, they do have some with the clip caps for cheaper but any with this style reservoir were about the same or more that I could find.

09-08-2012, 11:30 AM
Got the master cylinder mounted, front brakes mounted, pedal and linkage built, all the lines runs, and the brakes bled.

I do think the 3/4" Master is more than needed though, I am only using maybe 1/2" to 3/4" of travel on the master cylinder which has about 1-1/4" of throw.

That's ok though, to make the pedal push nice and easy, I simply adjusted the leverage on the pedal until it felt just right.

Came out really good and I feel MUCH MUCH better now about the brakes. I think the front end has a touch more braking power than the rear, but I'm going to take the kids out and go test it out this weekend some more..:D

New Banshee Front Calipers and the 3/4" Master Cylinder all mounted up.
The GSXR600 rear caliper
Not painted or permanently mounted, but the brake lines and Tees were all mounted on top of the upper a-arm box to keep them out of harms way. I just used premade 3/16" hard lines I found at NAPA. Most were 3/8-24, but two of the 8" lines were adapters from 3/8-24 to M10 to plumb to the banshee hoses. I ended up buying three premade 8" lines and one 61" line in 3/16" size.The Tees were all 3/8-24 inverted flare Tees. I went from the master cylinder up to a Tee that splits front to rear, and then on the front I split again for each side front caliper. The rear, I ended up fabricating my own 3/8-24 banjo bolt because I couldn't find one locally to convert the hard line 3/8-24 to a banjo bolt using a regular union. The bends of the hard lines I just did by hand, which I've never done before but the 3/16" hard line seems to bend pretty easily.

The pedal and bushing I all made out of pipe and 3/4" brass stock, 1/2" bolt and 1/4" tabs again all built from scratch. I made the pedal extra long so the kids could have plenty of leverage, but I might shorten it a bit after testing some since there seems to be more than enough stopping power now.

Pretty much my first brake line/system fabrication and it went easier than expected.

Brakes are GOOD![smilie=jumping.gif] Time for some testing..:D

09-09-2012, 08:44 PM
dang, you don't waste any time at all. good job on the brakes/pedals. really compact in there.

09-09-2012, 11:18 PM
Thanks! It was already pretty much all setup for front brakes (Already had the banshee spindles and discs mounted before) as I was thinking about adding them in the future. I also had the banshee calipers on the big buggy and sort of "Borrowed" them:eek:

Never got around to a full dirt outing this weekend (Planning a dirt run next weekend instead), but the brakes work really well in quick pavement runs near the house. It really made all the difference in the world, darn near stops on a dime now with very little effort. It went from an uncomfortable slow down, to MOAR than enough stopping power which is good.

Anyhow, I'll give it a good dirt test run next weekend, but I think the kids buggy is pretty solid for the dunes at the end of the month. Just gotta mount the paddles I bought and it should be good to go.

Time to get back to the big buggy build..:D...need some more brake calipers now..:D

09-10-2012, 08:53 PM
Nothing major, but I got my craigslist find $40 20x12x10 used dune slider paddle tires mounting on some old aluminum honda 4 on 110 10" rims I had today. Had to get a looksy on the buggy with one tire on and the kids volunteered to pose for scale reference...:)

The 12" wide tires are pretty beefy and look cool....all set for our dunes trip at the end of the month.[smilie=jumping.gif]

09-11-2012, 12:47 AM
Hey the buggy is looking great!

Check out this find I spotted on youtube.
Long travel buggy - YouTube (http://www.youtube.com/watch?v=9q5jbeIdsBQ&feature=plcp)

09-11-2012, 03:15 PM
Awesome job Martin!

Your a talented fabricator,car looks great.

RGV,that vid has been posted before.That guy is a professional builder.Thats one of the coolest kids cars I've ever seen.Theres some of her driving it also.

09-23-2012, 10:41 PM
Yeah, that's a sweet car.

Took the kids buggy out last weekend and let my son take it around a friends property. I also got in and put it to the test. The brakes work awesome, that upgrade was a major success.

Did a little more in preparation for the dunes this coming Thursday. We might take it for a night ride, so I figured...lights would be good. I doubt the little industrial motor can crank out 100 watts, but that's also why I left the pull start cord as backup just in case..:)

Found the headlights at walmart. They are sort of a trailtech knockoff using MR16 50W halogen bulbs. $19 was the right price. Taillight was a trailer marker light for $8.

I'll try to get some decent video at the dunes next weekend, although my son seems to be more interested in his 250ex quad, I'll probably be cruising with my daughter in the trails with it. Can't wait.[smilie=jumping.gif]

09-24-2012, 08:19 AM
Nice tires!

09-24-2012, 01:18 PM
Thanks...hope it can turn them in the sand ok and not push the front end around too much. I would like some front sand tires too, but I already overspent my monthly toy allowance...:)

I think it will do ok, seems to have a fair amount of more torque and power than my son's 250ex. Really lokking forward to this dunes trip later this week. Can't wait to hit the trails with my daughter, she is such a hoot to ride with and can't seem to get enough screaming and yelling with her arms in the air as the buggy becomes roller coaster...:)

10-01-2012, 10:12 PM
Took it to the dunes, it did really well. Sorry for the poor camera ability, but this is all I could bring back. A poor attempt at chasing my better half and daughter while trying to ride my son's 250ex with one hand while the left hand was holding my phone...lol

KidsBuggyDunesTest.mp4 - YouTube (http://www.youtube.com/watch?v=hUCMMXl-2Fc?t=6s)

10-01-2012, 10:17 PM
Nice bit of multi tasking there Martin ,,,,,,,cool lil trails,, buggy looks a perfect fit :)

10-01-2012, 10:30 PM
Thanks! If it wasn't for the auto-clutch on the 250, I'd really be having trouble. One thing I really like about the south end of the Oregon dunes is all the woodsy trail system, but some of them are pretty narrow. The kids buggy is right at 50" in width which is a great fit and hoping my bigger buggy at 60" will still fit a majority of them. When the open dunes are too windy, the trails are usually a great place to tool around. Some of them are really windy built up with berms and lots of ups and downs. Lots of fun, just gotta watch for them tree roots, they eat wheels and tires for lunch..:)

10-02-2012, 05:57 AM
looks like the little buggy performed well... also looks like you guys/gals had a great time. :)

10-02-2012, 06:36 AM
looks good Martin!

10-02-2012, 06:56 AM
Cool vid Martim.. I am suprized how that kart gets it ,in the sand and your kid getin out of the buggy and flipin her helmet off brings me back to when my boy was that age "He did the same thing" Now its a 16yr old W/an attude:mad:

08-19-2014, 05:42 PM
Just an update to this ol thread.... I bought this mini buggy from Martin!! I was asking his opinion on CVT's for mini buggies and he pretty much sold me this whole buggy for the cost of just the CVT!!!

I'll start a new thread for it's transformation in the future, gotta finish Tubby first.... But, my plan is to use all the parts on this buggy to build a DRIVERS ED BUGGY!!! It will have two sets of controls, one set on the left for little people, and one set on the right for Adults (well, at least adult sized people, I know I am more of a large child myself....) With this setup I'll be able to teach my nephews and my little one (soon to be plural... wife is due in October!! yikes!!) how to drive in a pretty safe manner :D

Thanks Martin!!!!

08-19-2014, 05:47 PM
Congrats MrB. sounds like a great plan.

08-19-2014, 05:56 PM
Happy to see the parts going to good use!

Don't hesitate to chop/toss whatever is useful. It was a bit of a build as I go unplanned project, so it would probabaly be best to scrap the frame and pull the parts off of it.

I had my fun experimenting and it is even smaller than the pictures seem to indicate.

The driver's ed idea will be really cool, the kids will have a blast!:)

08-20-2014, 02:07 AM
Wow! Im really impressed at how well it hooks up with a child and an Adult along with it only running the 6.5HP!

I have 2 of those engines sitting in my shop and have been wanting to build something for my Nephew!
You guys have to stop posting all these videos, It keeps making others want to build more and more!!!

Mr.Bracket, Good deal on the buy! looking forward to the changes! You guys really are the Buggy Buddies!!!

Is the 6.5 Degoverned?

I've been to Kart races where I have seen guys running Track Karts with Dual engines and they were pretty bad ass!!! A few of the old timers said they can run them with different clutch configurations. I've always wondered about that and how it would benefit in an offroad setup like the kids Buggy.

I even contemplated on running 2 engines, 4wd. 1 in Rear and 1 in Front! Hmmmm???

I have a Go kart Chassis, Chinese 350 Quad Tires Spindles and wheels, and the 6.5 waiting to be put to use. I think I may build the kid Kart before I get into building the 16HP buggy! Dual Degoverned 6.5's may be the ticket!!!

08-20-2014, 02:45 AM
The last video was with the 16HP motor and Comet 500 clutch. Intake was adapted to a 3" car intake, drilled out the main jet, and built an exhaust using my old KX500 silencer.

I did start with a 6.5, but switched over to the 16HP later.

Zip tie on the govenor spring, but the motor was untouched otherwise.

The 16HP did really well, not enough to climb real steep dunes but it did give the 250ex a run for it's money, I had a hard time keeping up with them shifting and holding my phone with one hand..lol

In the dirt, the buggy is really quick but the govenor is a good way to limit power.

Comet 500 clutch also a great match. Great combo..:)

08-20-2014, 07:07 AM
So thats the Single cylinder 16HP?

08-20-2014, 07:21 AM
Martin! I just watched the video again!
I Love It! First time watching I only made it halfway before having to cut out, But that thing does really well!!!
Sizing is perfect for 1 adult and child, and power to weight ratio. It even did good over the Whoops!
Along with a great budget way to have family get out there.

Hope you have more video.
The Video Stabilizing almost makes the rear look like it has Lateral Articulation!

08-20-2014, 07:37 AM
This is the only one I found with 2 6.5's. But it doesn't look to bad!
He gets booking down those roads. Not sure how difficult it would be for tuning and or dune torque. Gearing would play key

08-20-2014, 08:44 AM
So thats the Single cylinder 16HP?

Yes, Duromax single cylinder 420cc honda clone with electric start:
Duromax 16 HP 1 in Shaft Recoil Electric Start Engine XP16HPE ID 166904 | eBay (http://m.ebay.com/itm/131262470274?nav=SEARCH)

They also make a recoil only model, really cool little compact motor and you should be able to do a lot of Honda GX390 type mods if you wanted to open her up.

Very reasonable cost on the motor, but the Comet 500 clutch is a bit spendy but worth it for offroad needs. I had a comet clone 30 on the 6.5hp and then the 500 for the 16hp. The 500 has a nice wide ratio and much more of a big boy torque converter. Bought a spare belt, but never needed replacing granted I only put about 40hrs on the setup.

Comet 500 primary

Comet 500 secondary

Comet 500 belts

Comet 500 tuning/spring info:

I never did any tuning other than sprocket and gearing it down to 9/60 #40 but the clutch is set up really well right from the box for this sort of engine. Worked well both with govenor (3600rpm max) and with a little opening up (4000rpm).

Had thought about dual motors a few times too. I think it would work fine with a CVT setup on each to a shared jackshaft hosting the secondaries. Would just have to sync the throttle on each but the clutches would cushion minor differences. Two gsxr600s though, not sure you could sync the gearing, you would probably need two shift levers to allow manual gear sync, that would be cool too though..:)