New Project Plans

[Doc Sprocket]

Howdy, y'all! I have officially broke ground on a new kart project. I stripped the donor bike today. It's a 1988 Yamaha Virago XV250. Air cooled, Vtwin, rated 22hp @8000 rpm. Comes with a 5-speed. I got the bike in running condition for $250CDN.
I should mention that this will be an offroad kart, it's bound to be quite unique. I got a frame out of the paper for $50. It's an onroad frame, but I think I can work with it. I'll stick in a couple pics here to give you an idea. I'm going to do a rear swingarm arrangement, haven't settled on the frontend yet.
(Having pic issues, will add them later)

 

[Doc Sprocket]

Pics...

 

[idontknow]

look this is my first post so hello everyone. ive been riding gokarts since i was 9 or ten, but i just got into all the finer details of wat maks them work like last summer since then ive fixed an entire front end on a kart i crashed a couple of years ago and now im trying to build a go kart with suspension. but i cant find any plans, i saw this really cool kart on youtube that some highschoolers made but cant find the plans, its called a dirt devil, so if anyone has any free plans or ideas it would be a great help thx!

 

[KieranM]

idontknow not trying to get a you or anything but you should not be hijacking other people threads. if you start your own thread more people will see it and you will get a more people replying.

Welcome to diy gokarts

 

[modelengineer]

Toystory it looks like you're off to a good start. That engine will sound fantastic and go like stink

 

[Kaptain Krunch]

thats one clean engine!

 

[freakboy]

with that engine you should do double a arms in the rear end! the ride will be much nicer and it would be a really kickass kart!

 

[Kaptain Krunch]

or trailing arms. There better than a arms IMO.

 

[freakboy]

it would be harder to do on his kart there. a arms he can weld tabs on and either go with bushings or heim joints then from there go out and just have 4 u joints. and a axle....

 

[Kaptain Krunch]

it would be harder to do on his kart there. a arms he can weld tabs on and either go with bushings or heim joints then from there go out and just have 4 u joints. and a axle....

true, didnt really look closely at the frame, it would be very hard.

 

[freakboy]

yeah.. you also need some good distance for trailing arms for some good travel...



also dont cheep out on the shocks.. the cheep ones are basicaly just springs i would get some good atv type that acctualy absorbe shock apposed to bounce your head loose.

 

[DK shredaaa]

the frame looks like a tank and heavy, nice motor

 

[Doc Sprocket]

I still haven't decided on suspension yet. As for the frame, I believe it's going to have a serious conversation with my Sawzall! Yeah, it's a little hefty right now, and if I was scratchbuilding it, it would be completely different. But the price was good, and a little hack 'n' whack oughta bring it a little closer to useful. As far as shocks go, I have two sets right now. One set is from the donor bike, the 88 XV250. I also have a set from a 1984 Honda VT750 Shadow. As the Shadow is a lot heavier, I would imagine those springs would be more appropriate for the rear of the kart.

The engine is pretty clean- I haven't even cleaned it! Can't remember how many miles are on the ticker, but I know it was stored for a few years. The only problem it has is an exhaust stud is broken off in the jug (AAARGH!!!), and it think I'm going to have to remove the jug to have any chance of extracting it. Runs well, though!

To keep it cheep, I was thinking of doing the single swingarm/ unsprung engine thing, but I want the rear axle to articulate, so I'm goofing off with a few ideas, yet...

 

[anderkart]

Sounds like a cool project there toystory. I was thinking you might get some (articulating) Idea's from the pics in this link: http://phoenix.craigslist.org/evl/rvs/1620295785.html

 

[Doc Sprocket]

Now that is neat! Thanks for the link, Anderkart! I see that it has the independant braking some of us were dicussing in another thread. I didn't know this was benificial in a sand rail- Surprise! The steering is very interesting too- they used a rack and pinion, but only to achieve a desirable ratio. Then it goes to a pitman arm, didn't see that coming...
As far as the rear suspension goes, that looks pretty good, but might be a little too much for my budget (and possibly) skills. Well done, all the same.

Somewhere in this forum (gotta find it), a fella built a rear suspension that is similar in fuction to what I have in mind. The engine is unsprung, riding with the suspension, and the whole rearend pivots up and down, and articulates on a large balljoint. It is located with a Panhard rod. I've been thinking about doing something very similar, with a Watt's link arrangement. I know that having the engine unsprung is not the best design by any stretch, but the purse strings are quite tight.

I also have access to a golf cart axle, but I suspect that it's ratio (as yet unknown) may not be at all appropriate.

 

[Doc Sprocket]

Ahh. Here we go. The thread was by dougthewelder. That took some digging. http://www.diygokarts.com/vb/showthread.php?t=5315

 

[Doc Sprocket]

My frame fought my saw and my saw won!
My frame fought my saw and my saw won!

Sorry. Annnnnyhow- I weighed it first (135lbs) and started hacking. I know I'm gonna put it all back, plus some, by the time the suspension and cage are built, but that stuff had to go. I ended up taking off 65lbs of dead weight that was no good to me, at least what I put back on will be functional. Still have to clean it all up, but I'll do that later. Now at least I can visualise what I have to do next. I think I'm going with single A-arms in the front. Oh yeah- found the speedo- 24000 original miles. Not bad, eh? I didn't bring my camera up to the shop, so the after pic is a crappy cellphone shot. Sorry.

Here's before and after.

 

[Doc Sprocket]

Okay. Started putting the weight back on. It's simpler/squarer than I'd like, but I don't have complex angle finding/ cutting equipment, or access to a bender. I could probably do it all by hand, but I don't have that kind of time. So be it. Meanwhile, If you guys have suggestions for triangulation or stiffening, I'm all ears. The basic cabin is only slightly taller than it needs to be to clear my head, and there will be a section grafted onto the rear to tie in the suspension. Cheers!

 

[Doc Sprocket]

Folks, I'm having a rough time trying to figure out how best to triangulate/ support the sides. Could one of you good folks toss me an idea? Maybe play with my frame in Paint?
Thanks a bunch- Chris.

 

[freakboy]

i would gusset the uprights in front
mabey add a peice from the top were its welded in the front to the frame... and in the back from the top of the welded bit to the center of the frame in the back