My '03 R6S shoved a valve sideways into the head. It also dinged up the piston. We have a donor '04 engine with throttle bodies and wire harness. But given what all we need to swap out on it parts wise I'm thinking it would be quicker and easier to just swap out a piston and the head.

First question of course is, will an '04 head work on our '03? Would the throttle bodies and black box need to be swapped too?

What about the piston swap? Can I just pop the piston off the rod of the donor engine and throw it into the recipient? Should I swap the rings out?


Thanks in advance for your help! :)

All you need is the head. The 04 head will work. Just swap them out, get the timing set then check, and adjust the valves.

All you need is the head. The 04 head will work. Just swap them out, get the timing set then check, and adjust the valves.

I'm finding that there are differences of some sort with the ECU between '03 & '04. Any reason why my current ECU & Power Commander setup shouldn't work? I can't think of any.

Somebody just told me that the head and top case on this bike are machined together and cannot be mix matched. Is that true?

the 03 and 04 are the exact same bike, just different years. Also the 06-09 R6S are the exact same as the 03. Anything can be swapped between them. Only the 05 R6 has some differences.

the 03 and 04 are the exact same bike, just different years. Also the 06-09 R6S are the exact same as the 03. Anything can be swapped between them. Only the 05 R6 has some differences.


Thanks. Including mix matching heads and top cases?

Thanks. Including mix matching heads and top cases?

as long as it isnt warped, i dont see a problem. although i have never swaped them on an r6 before.

they are supposed to be the same. yamaha made no changes from 03-04. and like already said, the 06+ "s" is the same as the 03 and 04.
if you are still in doubt look up the part numbers

Thanks, guys.

Yeah, I checked part numbers and they're all the same.

I also just noticed that the crank case (upper and lower) is sold as a full assembly, which indicates that the upper and lower cases probably should not be mixed matched. Seems that would be the case for the head too if that component was a "match set" with the cases, which it appears not to be.

Good question...

I dont see why you couldn't mix and match. They probably just sell them as a whole cuz its cheaper to do that. Remember, all the "whole" parts on a bike are just a completion of individual parts. Shouldn't matter if its one year top and another year bottom.