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ricky.wells33
03-20-2019, 07:38 AM
I built this truck for my son from scratch. It was my first build and I learned alot. Theres alot of things I would do differently if I had to do all over again but my son absolutely loves it. The problem is the truck is pretty heavy and I only installed one small disc brake designed for a normal go kart on the rear axle. With the weight of this truck that one brake isnt enough to get it stopped quickly or if its on an incline it doesnt want to stop it at all. All 4 hubs are 4on4 bolt pattern so that I could run golf cart wheels and tires on it. Any suggestions on a brake upgrade so I feel safer with my son driving this? Id love to have front disc brakes but cant seem to find any that will work. https://uploads.tapatalk-cdn.com/20190320/ba798075ce00bf046e1712ec9aa05cf5.jpghttps://uploads.tapatalk-cdn.com/20190320/8d0219e29262da94ce4c3e43caa6c965.jpghttps://uploads.tapatalk-cdn.com/20190320/84c4e005b5559eecc3b0d77d0b0e11ba.jpghttps://uploads.tapatalk-cdn.com/20190320/7afe3876f963a4536d58f0b3f8dcec07.jpghttps://uploads.tapatalk-cdn.com/20190320/fef441166854d1f9a2c6f5aea3686f53.jpghttps://uploads.tapatalk-cdn.com/20190320/9b659681627c78009063f8c30779500a.jpghttps://uploads.tapatalk-cdn.com/20190320/d574dde6e01477282a669c61f99cff1b.jpghttps://uploads.tapatalk-cdn.com/20190320/fa9041e1732dd3fdb1c86121df9438fa.jpghttps://uploads.tapatalk-cdn.com/20190320/1e433b6c507dda60681d114235dd6faa.jpghttps://uploads.tapatalk-cdn.com/20190320/f272db025979a3f13cb2b69bed127bd6.jpghttps://uploads.tapatalk-cdn.com/20190320/822e89a5fec9472c9d02076cd68535cb.jpg

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CARLRIDDLE
03-20-2019, 09:11 AM
Great looking ride!!!

Are the brakes just a cable or are they hydrolic w a small master cylinder? I used some calipers off a quad and had some small rotors made mounted to back of hubs. I think ya could squeeze them in and while small diameter I bet ya could lock up tires.

ricky.wells33
03-20-2019, 09:16 AM
The one brake is hydraulic with a master cylinder. Its just very overworked.

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fatboy1214
03-20-2019, 10:22 AM
nothing productive to add I just wanted to say that thing is sweet!

ricky.wells33
03-20-2019, 10:23 AM
Lol thank you. Im proud of it, just wish my boy could ride it more.

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Frank
03-20-2019, 12:34 PM
Looks great !!

No expert by any stretch, but did recent upgrade myself. Looking at your pics, I would look at adding a second rotor and caliper to the rear axle. some things you may want to consider...bigger calipers that would offer larger brake pads and pistons. another thing would be an upsized master cylinder.

Again, no expert. Hope this helps.

ricky.wells33
03-20-2019, 12:57 PM
Actually yea it does help. I have a bunch of parts laying around from a few crotch roacjets that I stole motors out of and I thought about trying to put the rotor and claiper from the front of one of those bikes on the back of the kart

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LIDUNO
03-20-2019, 01:07 PM
Could this simply be a leverage issue? Can you lock up the rear brake? If you can get them to lock up, but your kid can't, you may just need more leverage on the peddle.

If that doesn't work, I would think a master cylinder and a 4 piston caliper from a motorcycle would do the trick. A larger rotor also increases leverage and stopping power.

With all that being said, having just a rear brake isn't all that great. Even if you get the rear brake locking up, having front brakes would be way better. Do golfcarts not have front brakes?

ricky.wells33
03-20-2019, 01:16 PM
No I cant get the back to lock up, the weight of the rolling cart just pushes right thru the brake. And yes golf carts have from brakes but they have a completely different spindle setup and Im not sure if they could be made to work or not.

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darwinpayne2000
03-20-2019, 01:54 PM
Are the tires using 8" rims?

My original buggy setup had 8" rims and the standard Azusa go kart 4-on-4 inch hubs and spindles that you find on most go kart websites, such as mfgsupply.com. Just as you describe, the single rear brake left a lot to be desired.

I picked up some 1/8" x 6" rotors that are used on racing go karts and some small calipers. The rotor had a 2" inner diameter that fit perfectly onto the front hub. I fashioned some tabs for attaching the rotor, but you could also weld the rotor directly onto the hub. I also cut a mounting bracket for the caliper with a 3/4" hole that slipped over the spindle. the final piece was a brake master cylinder that had connections for both the front and rear brakes.

My buggy is probably about the same size and weight as your son's truck. The four-wheel disc brakes made it stop on a dime. I was amazed at how well the setup worked with those small rotors.

You can probably keep the single rotor on the rear-end because the front brakes are what really make the difference when stopping. If you're interested, I can post up some pictures and list out a source (or sources) for the parts.

ricky.wells33
03-20-2019, 03:34 PM
Darwinpayne that would be great. Ill have to check but I think the rims I used were 10 inch. So shouldnt be any issue fitting

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Bullnerd
03-20-2019, 04:08 PM
Nice job!

ricky.wells33
03-20-2019, 04:09 PM
Nice job!Thanks

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LIDUNO
03-20-2019, 06:40 PM
https://uploads.tapatalk-cdn.com/20190320/f272db025979a3f13cb2b69bed127bd6.jpgConsidering the topic, the shirt is perfect..lol

ProtoDie
03-20-2019, 07:46 PM
cool looking truck!
I agree with previous posts
one caliper on the rear will stop it

1. I would run a 1/2" to 5/8" master cylinder,
2. 8-10" dia rotor
3. if the MC is low on the frame, try adding a 2 lb residual valve
if still not good enough
4. add a 4 piston caliper.
I run 4 piston wilwood, part # 120-6818 caliper with brake pads 150-8850K on single rear brake buggies
pricey though. A used motorcycle caliper should be able to do it too

3. make sure you have enough throw / leverage on the pedal. depending on the pedal location, may have to go to a hanging pedal to increase leverage

and bleed, bleed , bleed and re bleed the brakes good. tiny bit of air in the system can take away all your power

ricky.wells33
03-20-2019, 08:06 PM
cool looking truck!
I agree with previous posts
one caliper on the rear will stop it

1. I would run a 1/2" to 5/8" master cylinder,
2. 8-10" dia rotor
3. if the MC is low on the frame, try adding a 2 lb residual valve
if still not good enough
4. add a 4 piston caliper.
I run 4 piston wilwood, part # 120-6818 caliper with brake pads 150-8850K on single rear brake buggies
pricey though. A used motorcycle caliper should be able to do it too

3. make sure you have enough throw / leverage on the pedal. depending on the pedal location, may have to go to a hanging pedal to increase leverage

and bleed, bleed , bleed and re bleed the brakes good. tiny bit of air in the system can take away all your powerhttp://www.nexgenoffroad.com/product-p/798520r3.htm

Could something like that be used? And if so how do I match up calipers to it?

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darwinpayne2000
03-22-2019, 02:35 PM
Sorry for the delay. Work intervened. As I stated the hub is a standard go kart hub that you find on a lot of websites with a 4 on 4 inch bolt pattern. The spindle is a 3/4" grade 5 bolt that's welded to the spindle assembly. This design is borrowed from the Shredder II buggy plans.

The front brakes are my own addition. The rotor is a 6" x 1/8" minilite with a 2" center hole. This makes it slide right onto the hub. If you're running 10" tires, you could go with a 7" rotor for more stopping power.

I bought 3" and 2" bimetal hole saws and cut a donut ring out of 1/4" plate steel. Weld-on tabs would probably accomplish the same thing, but I thought the ring would make it easier to get everything perpendicular to the hub. Also, in hindsight, 3/16 plate steel or just tabs would have been sufficient. I drilled the mounting holes through the ring, using the hub and the rotor as the jig/mockup for drilling the holes.

I cut a rectangular piece from plate steel as a bracket for mounting the caliper. I drilled a 3/4" hole for slipping the bracket onto the spindle. I slipped the rotor onto the hub, then figured out the distance and the hole spacing for mounting the caliper onto the bracket. the bracket needed a big notch in the end to clear the caliper. I fitted everything together to verify alignment, then I tack-welded the donut to the hub. The rest was just welding everything up.

The pictures will probably explain the rest of the story. After I built the front hubs for 8" tires, I moved to 10" tires with a different bolt pattern. (Yes, everything looks rusty. A work in progress, I'm afraid.)

The minilite rotor is listed on Ebay, along with the go kart 150 brake calipers and the master cylinder. I've included pictures of each

36634 36635 36636 36637

darwinpayne2000
03-22-2019, 02:38 PM
Here's the additional pictures of the items on Ebay. Apparently, there's a limit of 5 pics per post.

If you're interested and want more precise measurements, let me know.

36639 36640 3664136642

darwinpayne2000
03-22-2019, 02:52 PM
Oops! Double-posted.

ricky.wells33
03-22-2019, 06:59 PM
Here's the additional pictures of the items on Ebay. Apparently, there's a limit of 5 pics per post.

If you're interested and want more precise measurements, let me know.

36639 36640 3664136642Thsnks alot for the info!

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Wheels
11-02-2019, 10:00 AM
Holy moly, that is awesome! Dang. Thanks for sharing.