clylinder and piston

[logg3rhead]

will a cylinder and piston from an 05 yfz fit an 06 yfz motor?

[James_yfz17]

first off, why on earth would you do that, the 05 has a smaller bore equalling less power. i know an 06 top end and piston will fit an 05 so i guess they are interchangeable.

The bores are all the same. yfz never changed that. they have different Cranks only. meaning different stroke. not bore. the 05 will bolt on no problem and work perfectly

[Titanium]

Originally posted by walshyfz86
The bores are all the same. yfz never changed that. they have different Cranks only. meaning different stroke. not bore. the 05 will bolt on no problem and work perfectly

04's were 439 cc. 06 and up are 449 cc.

Thats because of the stroke in the crank. not the size of the bore.

2006+
95 mm x 63.4mm

2004-2005
95 mm x 62 mm


That stroke is what makes up for the cc's. Not the actual bore. Thats why if you buy a 06 crank or a wr crank for the 04-05 it makes it a true 450.

[Titanium]

Originally posted by walshyfz86
Thats because of the stroke in the crank. not the size of the bore.


2006+
95 mm x 63.4mm

2004-2005
95 mm x 62 mm


That stroke is what makes up for the cc's. Not the actual bore. Thats why if you buy a 06 crank or a wr crank for the 04-05 it makes it a true 450. :blah:

learn something new every day...:blah:

[logg3rhead]

Thanks guys for all the help,

The reason i asked is because the hose from my airbox to my carb came loose and sucked a bunch of dirt into my cylinder and destroyed the coating. I dont have alot of money to go and recoat my cylinder and buy a new piston because im in college. So i saw a cylinder and gytr piston on ebay that had only 5 hours on them in excellent condition and won the bid for a little over a 100 bucks, not thinking about it being off an 05 and i have an 06.

Thanks for all the info