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mgies
05-28-2014, 09:01 PM
1983 ATC 250 R

I'm moving to Alaska soon. From 1/4-1/2 throttle, the engine sputters then picks up at half throttle; I know my jetting's off. Even yanking on the handlebars it won't wheelie. The trike has stock exhaust, Boysen power reeds, stock carb and stock jets, and a Uni air filter. Any help would be appreciated.

Thanks

DohcBikes
05-28-2014, 09:08 PM
Looks like you figured out how to post:welcome:

You said you 'know' your jetting is off. Buy jets. the 3 sizes bigger and three sizes smaller on the main and maybe one bigger or smaller on the pilot. So many people want to know the correct jetting but they dont order jets. Order jets, they will get used sometime.

Enter somebody that says its neither because its at a certain throttle position,,,well, its not so cut and dried as most people make it sound so be aware of that. pilot overlaps needle jet overlaps main and such so dont det stuck thinking its one thing. Make a significant change in tuning while recording original and modified settings and the results.

If it works, do it more. If it made it worse, go back the other way. The most important thing is that you ACTUALLY go outside and tune it, then post results. Days on days can be spent talking about it and if we dont make changes we will never know.