white_fly
white_fly Reader
7/14/17 5:59 p.m.

As I've been getting into autocross in rental cars (another subject for another day), I've been telling everyone who would listen that I wanted to get a shifter kart. One of those people sent me this listing, suggesting it might work.

I jumped on it right away. The seller turned out to be a very cool gentleman and I was more than happy to pay the asking price. What did I get? Well, I'm still figuring all that out. See, I know and love cars. This is another story. This is just a way for me to go fast and I know almost nothing about it.

So, that's where this build thread comes in. Part of this is documenting things for my own sake, part of it is sharing experiences with the world, but quite a bit of it is hoping that I'll get some useful guidance.

The frame itself is a Tony Kart, but I can't tell what year. Several of the parts interfaces on the frame have quite a bit of play in them, from the pedals to the side bumper supports. This will need to be sorted out.

The engine is a '99 CR125 that seems not to have run in some time. I was told that it has a 6-speed transmission and was modified for more power, but had trouble shifting which was diagnosed as possible bent shift forks. I talked to John Sefcik of SRS engines who specializes in stock CR125's looking for information about the transmission since '99 CR125's came with 5-speeds, and he said it is almost certainly a '96 or '97 6-speed but there's a "99% chance the problem is outside the engine." He suggested it might be the linkage (which does have a fair bit of play) or the seat moving around and interfering with the linkage.

EDT
EDT New Reader
7/14/17 7:28 p.m.

Certain things on karts are often loose so as to not interfere with the flex of the chassis. Most modern karts run the side pods with a bit of play, as well as the rear bumper.

And I am not very well-versed in older machines, but it looks like you either have an extended front porch or an older design to the front of the chassis where the pedals attach. Make sure it looks factory and not something poorly cobbled together. It would not be a good day if the brake pedal were to shear off unexpectedly.

white_fly
white_fly Reader
7/15/17 10:45 a.m.

The kart really did come with a ton of extras.

There's a set of three used wheels, one brand new set of wheels, two old but unused sets of tires, a tire installing tool, a bunch of extra gears...

...extra hubs (one has some bolts that need extracting), possibly a flywheel tool?, exhaust bracket, aluminum alignment discs, ballast...

...a bunch of extra two stroke oil and a funnel (which I won't bore you with a picture of), extra engine case halves, some random pistons and other engine stuff... ...MyChron 3 with data logger, laser alignment tool, kart suit and rib protector, trackside transponder, and probably some other stuff. Hopefully it'll all come together into a fun project. For now, I'm pretty pleased with the purchase. Time to get it running!

white_fly
white_fly Reader
7/20/17 11:08 p.m.

Some karting guys suggested I rebuild my brakes rather than bleeding them. It's a good thing they did! Not a single piston was moving freely.

After cleaning up a good bit of mess I discovered the bores were less than perfect. I picked up a hone and will be working on that.

Finding rebuild parts has been an interesting lesson in the world of karting. While kart design hasn't changed fundamentally since my kart was made, it's over 18 years old and borderline vintage! The kart has an old Biesse brake system that has been out of production for a very long time. Where standard fittings of very similar sizes would be easy to find anywhere in the US, it uses almost strictly metric sizes. A notable exception is the apparent use of 1.25" seals on the rear caliper.

The brake lines seem ok, but there are a couple of nicks in the sheath and I'm wary how old they might be. I read that many karts use nylon lines and this seems to make sense to me. The trouble is finding the lines and fittings in metric sizes. If I can replace all the lines and fittings for a reasonable price, this would definitely be the time to do it. I believe I need 6mm compression fittings and lines, but I need to double check that.

I found the "cup seals" or "lip seals" for the calipers at some kart parts suppliers, but I would like to try to find either a local source (Tampa, FL) or a cheaper source online.

Gaunt596
Gaunt596 Reader
7/21/17 2:01 p.m.

McMaster Carr might help on the seals, provided you have a rough idea what kind of rubber the seals are.

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