Yamaha yfm250 bear tracker carburetor

[Quin]

Recently bought a yamaha beartracker and found that it was more powerfull than another beartracker i already owned so decided to swap carb from one i bought which was an original mikuni carb to other one which has a cheep chineese one in it but it did not like it at all and was bogging under load at full throttle ( leaning out) so just changed it back to original chineese one and it was happy again. Just tought it was strange that 2 identical bikes did not like each others carbs. It also was nothing to do with retricted fuel on one bike as there is plenty of flow on both bikes. Anybody any ideas?

[Mech]

Do those things have two throttle cables going into the carb ? Perhaps one bike has a different/faulty cable splitter box. Perhaps the cables need readjusting for the different carbies.

Did you try the other bike, with the other carby ? How did it go?

Edited January 19, 2022 by Mech

[MarkinAR]

Almost any 2 identical machines of any kind behave differently.  My father years ago kept a fleet Toyota truck for parts delivery, had probably 30 and they were all identical except for color.  Sometimes you'd have one that would light the tires up, one that was slow as a turtle, one that got 30 MPG and one that got 14 MPG.