TY250R carby jetting

[Tim Stone]

Can any one suggest the perfect jetting sizes for a TY250R (1991 Pinky) Carby is a TK Y26P STD main jet #145 and pilot #42

[FM350]

Its difficult/impossible to jet a badly worn carb properly, but things can be improved through replacing wear parts like the needle and needle jet, and checking that everything else is to OE spec.

[The Hell Team]

Drop the main to at least a 140. Even leaner depending on altitude and ambient temp. These were always toooooooo rich straight from Yamaha. No need to touch pilot or needle.
Note: there is NO such thing as "a perfect" set of jet sizes for all conditions, locations and fuels. Take some time and search the net for material on carb tuning, there is plenty out there, or email me directly and I will send you some good stuff to help YOU analyze the way to achieve a sweet setup.
Regards

[FM350]

As you have someone who seems to be an expert on OKO carbs for trials bikes, based in Aus, then why not contact him and see if he has one to replace your worn TK?