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lost26
09-07-2014, 12:09 AM
Need some help here. I'm putting a gx620 in my sons buggy and really do not know anything about torque converters or a cvt set up. His little buggy should weigh roughly 400-500lbs, I need it to hook up to a polaris outlaw irs axel carrier with a 38 tooth sprocket and polaris outlaw atv wheels . From what I've read on here maybe a comet 94c drive clutch to a 100d driven clutch with a small sprocket on the shaft to the 38 tooth sprocket... Am I on the right track or just rambling complete crap? [smilie=alright.gif]

rgvkid
09-07-2014, 12:50 AM
Post some pics of what you have and then we'll go from there.

What size shaft does the GX620 have?
That'll be a nice engine setup for the buggy. Degoverned, Carb, and exhaust will put out some good HP!

lost26
09-07-2014, 08:08 PM
Hey rhvkid, it's a 1" shaft, I'll get some pics up today

mech_head6
09-08-2014, 10:10 AM
First thought that comes to mind is to use a 90s Polaris ATV transmission with chain drive to the rear. You would get FNR, which is a plus, and there are different gearing options in different boxes.

darwinpayne2000
09-08-2014, 01:50 PM
Your first thought is roughly correct. A Comet Duster driver/driven clutch setup would work, but you probably need to gear it down a bit with a primary/secondary jackshaft setup. The driven clutch would be mounted on a primary jackshaft with a 4:1 ratio between the primary and secondary jackshaft. The secondary to axle ratio would be 2:1, which would give you an 8:1 final gear ratio.

As Mech_head stated, another option, is to use a Polaris transmission setup. Pick up a Polaris ATV primary clutch and use a 1" keyed shaft-to-tapered shaft adapter to mount the clutch on your engine. Use the Polaris secondary clutch and transmission to add reverse (which is nice) and to also gear it down to match the sprocket on the rear axle.

The only downside to the transmission setup is finding a place to mount everything. You'll probably need to mount the engine a little higher than you were thinking in order to make room for the transmission.

Several guys have built buggies using a Polaris transmission. Maybe they'll chime in and post a few pictures.

mech_head6
09-08-2014, 02:01 PM
Team Ind and others make a primary clutch that will bolt on a 1" keyed crankshaft. You could also have a machine shop bore the ID of a clutch and broach a keyway. That's what we used to do for our baja clutches.

Not the cheapest option:
TEAM Aftermarket | Parts and clutches for ATV, Snowmobile, Golf, UTV and motorsports (http://teamaftermarket.com/parts-catalog/driveclutches-0)

We used 2 different versions of ATV trans in our build. Both can work well. There should be some pictures in the thread linked in my sig.

poordad
09-08-2014, 02:55 PM
Your first thought is roughly correct. A Comet Duster driver/driven clutch setup would work, but you probably need to gear it down a bit with a primary/secondary jackshaft setup. The driven clutch would be mounted on a primary jackshaft with a 4:1 ratio between the primary and secondary jackshaft. The secondary to axle ratio would be 2:1, which would give you an 8:1 final gear ratio.

As Mech_head stated, another option, is to use a Polaris transmission setup. Pick up a Polaris ATV primary clutch and use a 1" keyed shaft-to-tapered shaft adapter to mount the clutch on your engine. Use the Polaris secondary clutch and transmission to add reverse (which is nice) and to also gear it down to match the sprocket on the rear axle.

The only downside to the transmission setup is finding a place to mount everything. You'll probably need to mount the engine a little higher than you were thinking in order to make room for the transmission.

Several guys have built buggies using a Polaris transmission. Maybe they'll chime in and post a few pictures.

X2

if you keep your eyes open you can find a decent set of atv clutches and a transmission for less then one new drive clutch, then just get this adapter Tapered Clutch Adapter (http://www.cartpartsplus.com/performance/clutches/tapered-clutch-adapter) or have your primary bored for the 1" shaft.

I have used the adapter now for about two years and like that I can have two clutches set up differently for the type of riding I plan on doing and just swap them out when I want to change.

I do plan on boring out multiple sets of clutches tho for the long term ease of use and fit.

lost26
09-08-2014, 05:02 PM
I have a Polaris trail blazer transmission and the driven clutch but I'm not sure if there will be room to mount it. I built the rear using the measurements from a different motor I was going to use until I decided that motor was going to be a bit underpowered. I have figured out a way to get the clutches to fit by raising the motor bit. Something like this is what I had in mind unless I can get the polaris tranny to work :) http://i924.photobucket.com/albums/ad81/lost26/jack.jpg (http://s924.photobucket.com/user/lost26/media/jack.jpg.html)

rgvkid
09-08-2014, 07:10 PM
Take the info these guys are giving you like Bible! They know their stuff!

If I were you, I'd scratch the setup like in your pic, bite the Bullet and go full suspension on the front and rear.
You'll thank me later. ;-)
That engine can put out a good amount of power and your gonna end up beating your chassis and your back with no suspension.
You should be able to easily pull 30-40mph on hard pack ground with that setup. Doesn't sound like much but it feels pretty fast when your that low to the ground! Good times!!!

lost26
09-08-2014, 07:58 PM
Hey rgvkid, It does have full suspension both front and back. It has trx450 front arms and shocks, the rear has Polaris outlaw irs arms, knuckles, hubs and shocks. I'm also running the outlaw IRS hub carrier as my live axel just like wheels did. I'll get pics up tonight to give you a better idea of whats going on. I'm just curious as far as my clutch gearing. I know nothing about torque converters or a cvt set up. Also I really appreciate all you guys chiming in to help, i have learned a great deal from all you guys and have become addicted. :D

lost26
09-08-2014, 08:45 PM
This is a pic from the rear
http://i924.photobucket.com/albums/ad81/lost26/image-14.jpg (http://s924.photobucket.com/user/lost26/media/image-14.jpg.html)

here is another of the back where the motor will sit. (the axle carrier is backwards in this pic, I was just checking my clearance on the brake rotor)
http://i924.photobucket.com/albums/ad81/lost26/image-15.jpg (http://s924.photobucket.com/user/lost26/media/image-15.jpg.html)

front suspension
http://i924.photobucket.com/albums/ad81/lost26/image-16.jpg (http://s924.photobucket.com/user/lost26/media/image-16.jpg.html)

side shot
http://i924.photobucket.com/albums/ad81/lost26/image-13.jpg (http://s924.photobucket.com/user/lost26/media/image-13.jpg.html)

rgvkid
09-08-2014, 10:35 PM
Oh Shit! Your on your way to a bad Ass little buggy there!

Have you cycled out the suspension without the springs yet?
I'm curious to see what travel numbers your getting with the front and with the rear CV's

If you brace the top of the shock hoops it will give you a nice Stout setup along with Reinforcing the hood tubes.
http://www.minibuggy.net/forum/attachment.php?attachmentid=31076&stc=1&d=1410222972

rgvkid
09-08-2014, 10:39 PM
There seems to be a nice little Mini MiniBuggy movement going on here!

I guess people are starting to realize the potential of the smaller engines and power to budget Ratio!

lost26
09-08-2014, 10:50 PM
Thanks rgvkid, I have cycled the front without the springs but just to check the clearance of the tires to frame. I will measure it to see where I'm at. The rear suspension is not tacked yet. I still need to do some measuring and get it on all 4's so I can get it righte. I didn't have any plans so Ive just looked at pics on here and others Ive found. My next door neighbor has a trx450 that I got all my front end suspension measurements from. I really like how it's turned out but without plans you have to get the parts then build accordingly, then undo that and do it again.. I like your brace idea on the front, thanks

Project X
09-08-2014, 11:07 PM
It Looks Great!!!!

Nothing wrong using a little trial and error.

I look forward to seeing a motor setting in place.

Keep up the good work.

Project X

lost26
09-08-2014, 11:09 PM
Thanks Project X, sorry I can't roll with you this weekend.. I was so excited then the ol boss dropped me on my head.

Project X
09-08-2014, 11:16 PM
That's OK,

I have 3 more trips to Little Sahara on the calendar, we will keep you in mind for a later trip.


Project X

Bullnerd
09-08-2014, 11:23 PM
Lost, is the relation between the wheel carrier and the center bearing carrier the same as in the quad? It's hard to tell from the pics but the center looks too high?

lost26
09-08-2014, 11:39 PM
Its a bit higher right now, I haven't set it in yet it's just sitting with magnets giving me something to work with. Where it is now I can move the arms to what should be full droop and full bump and the axles still have a couple inches each way before they start to bind. It actually looks higher in the pic than it actually is, especially on the side view. I will have to cut the axles and sleeve them, my Aarms are mounted wider than the outlaws.

lost26
09-12-2014, 02:33 PM
After setting the motor in place I only have 1 option where I can fit the polaris transmission. My next problem is where I can fit the tranny, It would have a 16" center to center spread on the transmission clutch shaft and the motors drive shaft. Anybody know if there's even a belt that will fit this distance?

MJ4x4PA
11-12-2015, 11:39 AM
is this build still in progress?

lost26
11-12-2015, 06:54 PM
Still working on it, frames done, seats mounted, steering wheel and all steering components installed. Front suspension is done. Working on driveline now. Just ordered axles, rear knuckles, brake discs and hubs. It's been slow progress I've been playing with my boys a lot and really on get to work on it at night when they're asleep or out shopping with mom. Ill get some pics up.

Project X
11-12-2015, 08:01 PM
Thanks for the update!!!

Looking forward to the pictures.

Project X

lost26
12-28-2015, 02:23 PM
http://i924.photobucket.com/albums/ad81/lost26/Mobile%20Uploads/20150920_173557.jpg (http://s924.photobucket.com/user/lost26/media/Mobile%20Uploads/20150920_173557.jpg.html)
http://i924.photobucket.com/albums/ad81/lost26/Mobile%20Uploads/20150907_204010.jpg (http://s924.photobucket.com/user/lost26/media/Mobile%20Uploads/20150907_204010.jpg.html)
http://i924.photobucket.com/albums/ad81/lost26/Mobile%20Uploads/20150907_203956.jpg (http://s924.photobucket.com/user/lost26/media/Mobile%20Uploads/20150907_203956.jpg.html)

I need to get more pics but I wanted to be sure I remembered how to upload pictures :p

Rat4020
12-28-2015, 03:19 PM
Looks great Tex :D By the looks of your frame a 20hp auta move it quite well ...

lost26
12-28-2015, 03:30 PM
Thanks Rat, The honda was one of those deals you can't pass, I figure it's easier and cheaper to govern it than it is to add power.. it will start off pretty limited and I will increase his throttle as he progressess. Everything is adjustable as far as the seat and steering and I will probably make the pedals adjustable as well.. I should have the engine and trans installed pretty soon. I'm have to make a mounting plate that will allow me to mate the trans with the engine and still be able to use the oem cvt cover. I'll get some pics of that too.

Wheels
12-31-2015, 02:02 PM
Saweet! I can't wait to see it go. Oh... And take more pictures. You know better than to post multiple shots from the same angle. Geez. Lol jk Lost. :D

chrisMX-15
12-31-2015, 04:07 PM
very sweet build and safe looking for the little guy!!!!!! im thinking of building a few of the smaller kids version one for my nephew he is 18months but all he plays with is cars and trucks lol if I didn't no better would think he is my offspring lol keep up good work and keep us posted

lost26
12-31-2015, 05:21 PM
Thanks guys, Wheels I'll get some more pics ASAP, got some friends here for the new year so it may be a day or 2.. I'm just as bad about wanting to see pics and here i am showing some leg but cutting page 2 out and leaving you hanging :eek:

Chris, I prolly went a bit overboard on the bracing but "when" he rolls it I want to know I did all I could to make sure he's safe.. He's got a bit of me in him and tries to push pedals through the floorboard..lol
Thanks for the compliment and I'll keep ya posted..

Project X
01-01-2016, 07:34 PM
Great Job Lost26 !!!!!!!!

Keep the pictures coming.

Your boy looks Ready to tear up the trails.

Project X

chrisMX-15
01-04-2016, 11:25 AM
I hear ya on the kid think my nephew who is 18 months is going to be the same way just started walking but he loves his cars trucks etc. he will be the one I build small buggy for

Wheels
12-04-2017, 09:12 PM
Lost26... where ya at?? Any updates?