TT250, 350 Warrior project questions.

[Downey26]

ok guys, need some advice.

I race vintage flat track, and I just picked up a 1980 TT250.

I want to make a short tracker and TT bike out of it, but my class is 0-400cc, so all those honda 350's and the suzuki 400's really clean house.

I have read DuggyT's Frankenbike thread and also some things from Fast Frank, so I think I know enough to be dangerous on this topic.

I have a few questions.

I don't have access to a machine shop, so putting the 350 warrior sleeve in the tt250 jug is a bit of a problem for me.

1. can I just take a 350 warrior jug and head and bolt it on the tt250 lower end?

2. if so, will I still need to shorten the sleeve?

3. can I use the 350 top end and put the 350 crank in? that would solve the 19mm to 20mm problem.

4. if I do re-sleeve the 250 jug to use the 83mm piston, do I still use the 250 head, or can I use the 350 head ( I like my exhaust opptions with the 350 better)

also, someone said that a suzuki piston would be a good replacement, just bore out the 250 cylinder, and make it like a 277cc or somthing like that.

if anyone could please help me out with some info, I would greatly appreciate it.

Thanks

Nick

[DuggyT]

Not sure about using a whole 350 Warrior top end. I'm guessing it wouldn't work, as if I remember correctly, it's a bit larger. I did have to trim off about 1/4" off the bottom of the sleeve. I started off with a 0.040" copper head gasket. I ended up having a custom 0.020" copper head gasket made and it made a bit more power with the higher compression and doesn't knock. It usually starts first kick after sitting for weeks/months. It sometimes takes numerous kicks to start after shutting it off while hot or tipping it over and killing it.

This motor turned out to be 312cc with one overbore piston size left. It runs awesome and numerous times I've got the holeshot (beginner/intermediate classes) against much more powerfull hp bikes. It hooks up well and has lots of grunt.

Hope your project goes well.

[Downey26]

so you think using all the 250 parts with the 350 sleeve and piston is the way to go?

what did you use for a carb? did you still use the pumper carb from the 250?

a guy at the track told me he used to indoor race a TT250 and he said he couldn't get it to run on anything but the pumper carb. just curious.

is the 0.040" gasket standard? where did you get it?

[DuggyT]

Downey,

If you found the Frankenbike thread from the past, then all the info I know is in there. I'd suggest cozying up to your computer and doing some reading.

About the carb I used. I bought a new Sudco VM carb that they set up for this motor. I'm extremely pleased with it. Starts first kick, jetted just right, no backfiring, no hickups, etc. I'd buy this carb again in a second.

Again, the way I went using all TT250 parts except the warrior piston worked for me with minimal work. Using more Warrior parts MAY work, but I wouldn't be sure.

Good luck.

Doug

Edited August 26, 2012 by DuggyT

[Downey26]

thanks Doug

I will try and keep this updated with my results.

[ELEPHT70]

Any news? I'm interested!

 

I'll go find this "Frankenbike" then...

[knudsen]

Unless my brain is fubar again, I think there was a few kits made. Maybe you can find a donor engine with the kit. I replied to elfy's thread and mentioned a link. I'll see if I can find it. Might at least be interesting for both of you.

[knudsen]

Unless my brain is fubar again, I think there was a few kits made. Maybe you can find a donor engine with the kit. I replied to elfy's thread and mentioned a link. I'll see if I can find it. Might at least be interesting for both of you.

Hahaha elfy is the one who found the mentioned link and passed it on... http://www.xt500.co/post41191.html?hilit=%20TT%20250%20http%20www#p41191