I read the atricle in dirtwheels about the 330EX and i was wondering if the sleve for that could be put into my 250X cylinder? If not will a 300EX top end fit onto the botom end of my X? I like having less weight and kick start and i dont want to trade for an EX unless i have to. Thanks!

Dave

 

These engines are basically the same except that the 250x has a shorter stroke than the 300ex, and electric start. They have the same bottom end so that should be no problem.

 

Yes, you can put a 300ex top end on a 250x bottom end....But...You would gain nothing because they have the same bore! To gain cc's. you would have to put a 300ex crank in your 250x. I can't remember exactly what, but I know something is different between the 2 cranks. I think the 300ex crank is longer to allow for the starter gear. It would probably be easier to have Powroll make you a stroker crank.

 

i think the 300ex 2mm more stroke.

 

letitsnow

you dont know what you are talking about, the 2 machines DO have a different bore the 250 is a 246 and the 300 is a 281 the 250 has a shorter stroke than the 300 also

thank you

 

Actually no, they changed the stroke and kept the bore the same size.

 

you are wrong too i have the clymer manual right next to me and a double checked it someone please back me up on this because i know that i am right

 

They both use a 74mm bore, but the 300 has a longer stroke. The 250 has a higher compression ratio.

 

longer stroke same bore!

 

exlax250x?? Lol.