Mulling 1st kart build

[jrbrtsn]

After seeing KartFab and CarsAndCameras on YouTube, I've got the bug to build a kart. After reading many of the articles and posts on this forum, there are still a few things I need to decide, and I'm hoping for some sage advice.

First off, my goals for this build:

* Single-seat kart suitable for anybody 13 yrs old and above to drive, regardless of skill level.
* Off-road only; yard and trails.

Things I'm pretty sure about:

* 14 guage ERW steel tubing for frame, probably 1.25" OD
* 6.5 hp Predator engine
* Torque converter
* Both rear wheels drive
* Disk brake

Things I'd like advice on:

* Solid axle vs. differential
* Wheel / tire combination - would 14.5 x 70-6 knobby tires be OK for front and rear?

Thanks in advance!

 

[KartFab]

id check out spidercarts.com for a nice off road build, as the ones I did are just simple go karts with zero suspension. 15x6-6 turf tires on front, and 18" tires on rear. Axle sprocket 60t, and the TAV2 comes with a 10t 40/41 sprocket, so maybe get a 9t or 8t sprocket for torque if you want to just putt around on steep trails all day. 10t is perfect all around and for hills though.

Id also look into rear swing arm, and front a arm suspension. Have fun man!

differential axles are 1) expensive 2) not really that awesome compared to a live axle.

have fun building!

 

[jrbrtsn]

Thanks for the advice, KartFab

One more question I forgot ask earlier: roll cage? It would seem that the chance of rolling a kart over on the trail is significant, and said kart could easily weigh 250 or 300 lbs. Of course the roll cage itself will add 40 or 50 lbs. Thoughts?

 

[crazykart]

Well you can cut some weight first off, try using 16 gauge 1.25" (or bigger diameter ) tubing instead of 14 gauge. Don't get me wrong 14 gauge is great...but it's also overkill, and really adds nothing more than weight. If you're worried about strength then go up in diameter size, not wall thickness.

Poke around ebay for a brake, look for hydraulic atv brakes, usually around $50 for a good set, and you'll thank me later.

If you have a-arm suspension up front those tires would be fine, but I would suggest at least 18" for the rear for ground clearance.

Axle, depends. What's your budget? In all honesty though you're going to be offroad, dirt, grass, etc: solid live axle will be more than fine.

Roll age for offroad imo is a need, but you don't need a full roll cage. Design a roll bar, somethings that sits behind the seat and sits higher than the drivers head by a good 6-8" minimum. That'll keep you from getting crushed, while not adding a massive amount of weight. I would suggest minimum 1.5" diameter tubing for that though just to be safe.

Others will chime in as well of course.

 

[jrbrtsn]

Front suspension

Thanks KrazyKart!

After a little research, it seems like using a salvage ATV's front spindles, hubs, and front+rear brakes might be the simplest strategy to end up with powerful brakes. The front suspension arms could be replaced with fabricated units matched to the kart design. Looks like a live axle in the rear is the way to go.

 

[J_Walker]

Check craigslist for motorcycle brakes!!

you can get 3 piston calipers for legit sometimes like 20 bucks. and sometimes comes as a whole piece. sometimes a whole set for like 40 bucks! [2 calipers and the reservoir and lever assembly]

then you buy a rotor like said above for your axle size of your kart. and attach the brakes to it.

lemme tell you, with 3 or even 6! piston brakes. UR GONNA STOP. [legit its over kill] lol you can easily get away with 2 piston calipers