2004 Crank in my 2003 WR450

Has anyone else tried this. I noticed that the 03 starter gear has a roller bearing and spacer that holds it in place, and the 04 has a brass bushing (like the clutch hub) and seems to float. Spent hours tring to figure out what is missing or changed. All parts from cam chain gear to the end of the crank are 04 parts. I have been all over Yamaha's parts catalogs and there is nothing between the starter gear and the cam chain guide (on the bottom of the rear cam chain slider). 2004 starter works much better and I know I won't have a key problem.

If you have a 2004 WR450 and been behind the rotor, do you remember if the starter gear "floats"?

Thanks for any help. :thumbsup:

I think the starter gear is on the starter clutch if that is what you mean by floating. Otherwise it will stay in place on the crank. :thumbsup:

The gear I'm talking about (gear 3 in the parts fish)sits between the Rotor and the cam chain gear on the left side of the crank shaft. the 2003 has no movement (crank has a ridge about 5mm from the lower cam gear, and then a washer that the gear sits aginst. The 2004 crank has no ridge and no washer. The gear slides into the "starter one way assembly" (that is bolted to the rotor and is one of the few parts that are the same for both years)the 2003 will not float and the 2004 will float (I hope). Anyway I can't find anything in the parts fish that seems to hold the gear in the starter one way assembly there is about 3mm to 4mm of movement. I don't think that this is correct... :thumbsup:

The gear is suppost to float. The starter and it's assorted gears hold this gear stationary until you push the button. Great mod, works awsom! :awww::lol::thumbsup:

The gear is suppost to float. The starter and it's assorted gears hold this gear stationary until you push the button. Great mod, works awsom! :lol: :lol: :awww:

What mod are you referring to? Are you saying to replace the one-way clutch assembly with an '04 model? I searched on partsfish.com but couldn't find gear #3 you were referring to.

I'm so confused... :thumbsup:

I too am very confused. :thumbsup:

The modification I'm talking about is installing a 2004 crankshaft (or just an 2004 crankshaft half) to an 2003 WR450. My confusion was: On the 2003, the starter "gear 3" (listed on the generator page of the parts fish, and yes it's part of the starter assembly even though it's on the generator page) bottomed out against an embossed ridge of the 2003 crank with a washer in between. On the 2004 crankshaft, which has no ridge between the cam chain sprocket and the end of the shaft, gear 3 has nothing between it and the cam chain sprocket. While the engine was still apart, the gear would slide back to the cam chain sprocket guide. After putting it together I found the rest of the starter gears and the starter it's self will hold the "gear 3" stationary. See the Yamaha parts fish under "generator" for the location of gear 3. The 04 crank works great in the 03 motor. By doing this you get the updated crank design and will never worry about the woodruff key again, plus when you upgrade to the 2004 starter design, you have all of the parts. If you do this mod you will have to replace all parts from the cam chain out. I tried to paste a picture showing gear 3 but did not know how. If you want send me your e-mail and I will send you a PDF of the parts fish showing gear 3

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