Need help with 1/2 scale truck

**ricky.wells33** · 03-20-2019 08:38 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.

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**CARLRIDDLE** · 03-20-2019 10:11 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 10:16 AM

The one brake is hydraulic with a master cylinder. Its just very overworked.

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**fatboy1214** · 03-20-2019 11:22 AM

nothing productive to add I just wanted to say that thing is sweet!

**ricky.wells33** · 03-20-2019 11:23 AM

Lol thank you. Im proud of it, just wish my boy could ride it more.

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**Frank** · 03-20-2019 01:34 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 01:57 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 02:07 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 02:16 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 02:54 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.