Offroad kart build

[SNGMA]

I recently started an offraod kart build for my son. He's only 3 1/2 but very into tools, building things and anything motorized. For Xmas all he wanted was a ratchet set and some pliers! He can just about change the oil on our cars, gets all the right tools for me and knows what they do. He has a honda 70 atc and an old snowmobile he rides around the yard. My brother has a hammer head 150 that he goes for rides in and has been asking he to build him a buggy since the summer. So, we started this project a couple of weeks ago. Let me know what you guys think so far.

 

[SNGMA]

More pics/info

For the front suspension we are using a yzf 450 front end: a-arms, hubs, brakes, tie rods & wheels. 12-14" travel

Rear suspension- still working it out but leaning to trailing arms with daul chains.

Drive train will be HF 212cc with a comet FNR box. Is this enough motor? I don't need him going to fast just enough power for hill climbs

Can I use a comet 40 with this motor? I'm eyeing one with an 8" secondary for more torque. I think it will handle offroad and the weight better than a 30. It also mounts in a better orientaion to the FNR for mounting location. Will this converter eat up much more power over a comet 30? Also a 40 allows for motor upgrade as he gets comfortable.

I'm thinking 18-20" ATV tires out back. For gearing: 10t on fnr to 14t on axle, then a 10t to 60t at rear wheels. Do you think that will be geared low enough?

Also just picked up this saw on craigslist for $60! Just needed a new plug end! Infinitely better than my rigid abrasive!
Thanks!

 

[jamyers]

... Let me know what you guys think so far.

I think I wish I were your son, LOL!




Sent from my iPhone using Tapatalk

 

[n1kogr]

this is awesome! such a lucky kid! Cant wait for more updates

 

[DaiSan76]

That looks very cool. I am planning to start something similar for the next build off. As to the power, the Predator should be ample power. I have a somewhat larger machine running 15 inch tires with a 16.5:1 ratio for my 5 year old, and it has ample pulling power with only a Centrifugal clutch and the 6.5 engine.

http://www.youtube.com/watch?v=hQ0yxHjJv04

Going to try and redo the steering this weekend. It kind of sucks right now.

 

[OzFab]

Man, that boy is switched on for a 3 1/2 year old; at this rate, he'll be welding by the time he's 5...

I could be wrong but, I'm pretty sure a 40 series driver aren't made for 3/4" shaft...

Other than that, it looks like you've done your homework & are progressing nicely.

Welcome to the forum

 

[souperman000]

I like the design so far. I understand why you would want the 4o series right now, but wouldn't a 30 be ok. I am just thinking a 40 wouldn't work to well withh the 6.5, but I'm sure you could swing it no problem.

That saw for $60? Man, those things cut metal real nice don't they? Just drop it on and it does the rest

to the forum!

 

[landuse]

Great job!! I wish I were your son. I would also use a 30 series if I were you, unless you already have the 40. If you are going to upgrade to a larger motor at a later date then you could try make the 40 work

 

[SNGMA]

offroad kart entry

I started a build thread under Photo Gallery & Project Log a few weeks ago. Since I have had no time to get any work done, I should still meet the less than 50% complete requierement.

I will update all progress on here going forward. I hope to get some time in this weekend

Steve

 

[Doc Sprocket]

Good luck!

 

[landuse]

Happy building!!

 

[SNGMA]

Gearing

I know it's been awhile since I updated my build but we have made some progress and I will post some pictures today.

I do have a question about gearing, my jackshaft and the final ratio for speed calculation:
If I run a 9t from the TQ to a 19 on the jackshaft and then a 9t to a 54t on the axle does it give a final ratio of 14? That's what I think but after looking at a few posts on here I'm not sure. It maybe 8.33?

I am going to purchase the last few items tomorrow.
Thanks in advance!

 

[chris_the_poser]

13:1 so what's the kart looking like now since the last time all I seen was the frame and a misc box o parts

 

[OzFab]

so what's the kart looking like now since the last time all I seen was the frame and a misc box o parts

It's not stated in the rules (maybe it should be but, how do we know what you've been doing for the last five months? How do we even know you built it? Case in point; my build log has over 200 posts, yours now has 6

 

[SNGMA]

It's not stated in the rules (maybe it should be but, how do we know what you've been doing for the last five months? How do we even know you built it? Case in point; my build log has over 200 posts, yours now has 6

I'm not sure what you mean? I highly doubt it's going to build itself. Although, that would be pretty sweet. I had a build log going under projects that showed more pics but I really didn't make any progress until late june after we had our baby. Its been crazy busy since and I didn't have anytime to update until now.
Anyway would it be against the rules to join the contest today and build it in two weeks??

 

[OzFab]

I'm not sure what you mean? I highly doubt it's going to build itself. Although, that would be pretty sweet.

What I meant was (& I'm not implying anything) How do we know you built it...

I had a build log going under projects that showed more pics

Oh ok, found it, maybe that should be here

My apologies for the misunderstanding

Anyway would it be against the rules to join the contest today and build it in two weeks??

No, as long as it's not 50% complete but, you don't need to worry about it as there is a build log, it's just not here... yet.

 

[Doc Sprocket]

Okay- this oughta do it. I've merged the two threads. Build on! EDIT- sorry folks, my bad. My brain hadn't yet joined the party...

 

[SNGMA]

Build Updates

I'm still sorting out a few things but here is a mock up of how it is comming together. I will post some pics of each stage of construction when I get my camera charged.

I am trying to decide btwn using a small rack and pinion I have or a steering flag like on the quad. Has anyone used a rack like the one pictured?

For the rear suspension, it was originally planned to be dual swing arms for irs. I may just go with a regular swing arm and get this thing finished. I have all of the parts to complete it either way. Would irs make a big difference on a kart like this?

For the gearing I settled on about 12:1, with the TC it should have plenty of low end.

Any suggestion are welcome, thanks!

 

[OzFab]

Steering rack: as long as the rack isn't wider than the A arm mounts, you should be good...

Rear suspension: Ultimately, IRS is the better choice of the two. the main reason is, if you're on rough terrain, one wheel will lift or drop but, with swingarm, the whole buggy will roll through the terrain. It all comes down to time &, as of now, you have a little over 2 weeks to go...

 

[Jim-L-L]

Looks very much like a Edge Sidewinder ! is it a scaled down version ?