New to Karts, need some help

[rifkin]

After living nearly 27 years of my life kart free I finally cowboy'd up and bought one.

I don't know the make or model, just that is has a 5hp briggs engine on it, some sort of cvt made by comet and I have made it run not so good. Nevermind that last part because the engine will be the first thing to go. I have completely removed the roll cage because it was too short for me and it just wasn't comfortable. I am in the process to doing something about the seat because the angle just doesn't feel good at all.

Now I have no real world use for this machine. This is going to be just for messing around though if I can get it to run at a good enough speed I would register it and run it on the trails here. I plan on swapping the motor for the Predator 212cc 6.5hp engine and then starting the modification route beginning with the exhaust and intake and throughout the summer getting the rest to do the full on piston, valves, crank, etc deal.

I was thinking about taking the cvt off of it and putting a 1:1 ratio clutch+chain+sprocket there. I think it would bolt right up correct? Something like http://www.mfgsupply.com/gomini/gominiclutch/gominiclutchcent/gominiclutchcentmax/4-455.html with a 12 tooth sprocket on the other side?

Anyways here are some pictures:

 

[r_chez_08]

Why do you want to remove the torque converter? The 5hp Briggs with the tc will perform better than the predator without a tc.

Another option for a new engine is the dupor or ducar yellow clones. If you plan on changing out the crank anyway, you may be better off. The parts are cheaper and more readily available for the 196c clones than the 212cc predators.

 

[Doc Sprocket]

Do yourself a huge favour- Service and KEEP the CVT. Not only is there no good reason to toss it, you WILL suffer a performance loss without it. Also- you might want to read up on gearing. a 1:1 ration will render your kart motionless. You need to be up typically between 5:1 and 7:1 overall reduction.

 

[flowerman]

NOOOOO dont get rid of the CVT for a crappy centrifugal clutch. Keep it it will work well!

 

[Doc Sprocket]

On second thought, mail me that crappy old CVT, and I'll send you that shiny new c-clutch...

 

[rifkin]

Ok so I will keep the cvt. How do I tell what model it is so I can get parts for it? On my sleds the belt on the secondary should be 1/8th inch above it and on this the belt is sunk right into the secondary.

As far as gear ratios are concerned The clutch to sprocket ratio being 1:1 would make the sprocket to drive wheel ratio the important one. Unless it needs to be 7:1 and then 7:1 again. I wouldn't think that would work too well though. I figured clutch, chain, and sprocket are cheap enough to try and dislike but if the cvt is the way to go so be it.

 

[r_chez_08]

Looks to be a 20 series but may be a 30 series or cat-99. Are the faces on the pullies symmetrical \/ or asymmetrical \|? Asymmetrical is a 30 series or a cat-99, and symmetrical is a 20 series.
Measure between the faces at the outside diameter on the driven pulley(where the belt rides) if asymmetrical. 5/8" is cat-99, and 3/4" is a 30 series.

The belt looks worn and sitting too low in the driven. Google 'comet (model) belt chart' for the correct belt.

Look for any obvious markings on the tc, which indicate to model.

 

[rifkin]

The secondary has some numbers one of which is 20 and unless the difference is subtle the belt is symmetrical. The cvt needs some overhauling though and a new belt.

 

[r_chez_08]

Sounds like a 20 series then.

 

[rifkin]

I ordered a new belt, I am going to order new tires for the rear soon as they both have some sidewall damage but are holding air just fine, and in two weeks time I will order the engine provided I do not find something local in the mean time. My brother in law is coming over with his backhoe and bulldozer and we are building a dirt track for giggles. Maybe it will spur some friends to getting karts or give me an excuse to buy another. I found my 2012 www.rockymountainatcmc.com catalog and was flipping through it. I would like to get new 'rims' for the kart but on the website it only lets you choose 'rims' by make and model and craigslist go kart isn't an option.

The back tires are 18x9.5-8 and the front is 145/70-6 if that helps. Would it also help to go with smaller back tires?

I also would like to figure out what size sprockets I have on it. Any way to find out other than taking it off and counting teeth?

Thanks for your help.

 

[r_chez_08]

You should be able to count the teeth without taking them off.
Smaller back tires increase acceleration and decrease speed.
What's wrong with your current rims? Btw 145/70-6 is a common quad size on chineese and kids quads (e.g. Suzuki lt50) so tires are easy to find.

 

[rifkin]

The rims are just dirty and old. They work, no issues there, I was just looking at new ones to make the kart look less dumpy.

I guess I will figure out my gear ratios and see where that would put me under optimal conditions. My driven clutch is 7" and I measured center to center at ~7.5" and ordered the 7 5/16 to 7 3/8 belt. My jackshaft and engine are on slotted mounts so I can adjust the ctc distance as needed.

Kenda Scorpions seemed like a decent priced at $40 per 18x9.5-8 tire. I will probably just end up buying something I can get at a decent price with decent shipping however.

 

[Jcotz]

With a little sandpaper and paint, the rims could look pretty good. If you insist on buying new rims, that is up to you.

 

[rifkin]

Over the past week or so I installed a predator 212, new clutch belt, tweaked some things, and then today fired it up and went for a brief spin. The driven clutch decided to eat the spring which I think was my fault because I moved the spring from #1 to #3 hole. I put up for sale in the buy/sell sub forum for 25+shipping but thats not my point to this post.

The kart was actually pretty fast and though I made it probably 800 feet today, it was a very quick 800 feet. The lack of suspension might enhance the sense of speed while offroad though. I was considering the exhaust / intake mods for the engine but that would put it above the 3-8hp range of the comet 20 and probably break more stuff.

I am not sure if I unhooked the oil sensor properly and I tried to hook up my kill switch but I guess I did it wrong? I unplugged the yellow wire coming from ...bunged plug? near the on/off switch. There is also another back wire near it but I left that one plugged in. There is a single wire leading to a bolt near the on off switch that I thought was a place to hook up my kill switch but I guess I was wrong since it doesn't work. I also managed to bolt the seat in and make it some what comfortable to sit in position wise. It is bare metal right now so it lacks comfort in that department.

Anyways, a productive day as well as a destructive day. I can't wait to get a new driven clutch and get this thing going again.

 

[landuse]

As far as I know, all you have to do is unplug the yellow