2003 YZ450F Using WR450F Crank/Flywheel/Stator

Is there a thread detailing this swap?  Trying to upgrade a 2003 YZ450F to run race lights.  Ready to split the case in half to fix a 4th gear problem, so now is the time.  Any help, direction, photos, part numbers, etc. would be greatly appreciated.  Thanks.

Out of curiosity are you interested in a wr trans as well? PM me if so. I have not seen any detailed threads on this. I have seen threads where it has been stated what would be needed but not anyone actually doing it. I thought about this mod my self a while back after I bought a complete 04 wr bottom end. I just could not justify ever putting in the time and money to do anything with it. Unfortunately all I have left is a plastic bag full of the transmission parts.

Unfortunately, almost the only way to accomplish this is to buy a whole WR engine.

The crank is different to support the larger rotor. The larger stator requires the larger WR stator cover, which will only fit on the WR crankcase.

On the other hand, the WR trans will bolt in in place of the 4-speed (as a complete unit only). Look for more info in Common Threads in the index.

Out of curiosity are you interested in a wr trans as well? PM me if so. I have not seen any detailed threads on this. I have seen threads where it has been stated what would be needed but not anyone actually doing it. I thought about this mod my self a while back after I bought a complete 04 wr bottom end. I just could not justify ever putting in the time and money to do anything with it. Unfortunately all I have left is a plastic bag full of the transmission parts.

Thanks. My pal might be interested. I'll forward this to him.

Unfortunately, almost the only way to accomplish this is to buy a whole WR engine.

The crank is different to support the larger rotor. The larger stator requires the larger WR stator cover, which will only fit on the WR crankcase.

On the other hand, the WR trans will bolt in in place of the 4-speed (as a complete unit only). Look for more info in Common Threads in the index.

10-4. Thank you.

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