Question by : aprilia rx with new piston, bad accelaration, doesnt go pass 4k revs? help?
hi, i just bought a aprilia rx 50 road bike, and its just had a new piston and bottom end, i took i down my local field and it worked perfectly until i accelarated in first, and no matter what the bike wont get past 4000 revs, unless its in neutral, any suggestions or solutions i would be very grateful :)

Best answer:

Answer by jon
Carb needs to be retuned and rejetted for the new bore.

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