250R stock carb size?

[annex138]

I have been looking at aftermarket carbs on ebay and i was wondering what size is the stock 85 250R carb? Also if i put a 38mm carb on my bike and jet it in will there be noticable power gains?

[timberwolf78]

im not positive but stock on an 84 250r is 30mm , so im guessing it might be 32 or 34 mm stock for an 85

[dunerash]

stock is 34mm on a 85.. im running a 39mm on a stock cly. (68.5 mm piston) if you have a good pipe on it, let it get enuff air in, it will run fine, hardest part is getting the big carb into your intake boot, can be quite a challange, it will add more performance to your trike, but youll also be going back to the truck to refuel alot more often..:)

[Mr. Richard]

yeah what he said!!! i'm running a 38 mm on one of my 250's , i used a cr intake boot cause its bigger so it was easy to mount the carb,,, i think you loose a little bottom end with a bigger carb . but the upper midrange and the topend are definitely stronger...............................

[250rAL]

I've got a 36PJ on mine. It fits in the stock boot without too much trouble and has great low end. Unless your cylinder is ported, that would probably be the way to go.

[dunerash]

not that i have any influence here, but i do agree with 250rAL if you throw to much fuel at a stock(un-ported/stock compession) motor youll have a tough time jetting a bigger carb..but if you get a 38-9mm carb, u might want to bump the compression up a little(shave the head/ or the dreaded CR head gasket mod) both are cheap ez mods... still think u should already have a good pipe and yer ride is in good"shape" before makin it go faster..:D these smiley things are kewl