300ex/250x compression

[zell250x]

what makes the 250x have a biger compression ratio than the 300ex. i was wondering because im planning on putting a 300ex cylinder and head on my 250x but dont want to lose compression.

[Sjorge450R]

Originally posted by zell250x
what makes the 250x have a biger compression ratio than the 300ex. i was wondering because im planning on putting a 300ex cylinder and head on my 250x but dont want to lose compression.

the shorter stroke. The same reason why a 50cc quad will have like 170lbs of compression when a 90cc quad will only have like 120lbs of compression

[am_muscle]

Isn't the 300ex cylinder and head the same as the 250x?

[zell250x]

the 300ex has long valvue springs. that is what the book said. but everything else is the same.

[Cody_300ex]

Originally posted by zell250x
the 300ex has long valvue springs. that is what the book said. but everything else is the same.

lol, the valve springs are the same.

[zell250x]

the manuel said they are longer on a 300ex. i havent measured but thats what the book reads.