are xsport cr3 engines the same as yx140 engines

[Domleadenham]

just been looking at a rebuild thread for a yx140 engine and it looks exacly the same as my xsport cr3 engine are they the same engine? apart from the top end obviously

[Dangle_kt]

nope.

primary clutch vs secondary.

[Domleadenham]

thanks so in your opinion which one is the better? also is there a difference in a cr3 engine and a standard xsport 125 engine?

[Dangle_kt]

difficult to say.

yx140 is faster, secondary clutch is meant to be better cos you can kick them when they are in gear.

cr3 lump are very good engines, quick for a 125, but dont have the best gearboxes if your planning on jumping (3rd gear can blow if you dont pull the clutches in on landing)

yx140 is a current engine, and so parts should be easier to get, and its still being developed so will continue to improve, and you can get aftermarket parts, none of those apply to the cr3, but its a very good engine and lasts very well.

[Domleadenham]

yeah thats the problem with mine the dreaded gearbox! but ive pulled the engine apart and the gearbox looks fine no teeth missing ect so im a little confused. i am mechanically minded but just cant find the problem!

[Dangle_kt]

is the shift arm bent? can cause the gear to not engage properly as the shift drum can't be turned accuratly