06 450 Clutch Question after full tear down

So I just got my bike running this weekend after sucking sand in through the crankcase breather hose. The bike runs very well, power is back where it needs to be, but my clutch is acting up. It makes more of a growl than it used to, I have had 3 450's and all of them have had noticable clutch noise when they are in neutral and you pull the lever in and out. Anyways the clutch is not fully disengaging either, it is almost impossible to get the bike into neutral while it is running from first or second gear. My question is what could the sand in the motor have done to affect the clutch like this? When I pulled the clutch plates out I had to pry each one off of its respective metal plate. The basket and inner clutch hub are both notched a little bit, but should not account for the whole problem I am seeing. Could the sand have ruined my fiber plates so that they behave like this? I noticed that it did this the last ride before I found out there was sand in the motor as well. Any ideas???

I don't think it's related to the sand thing. In the first place, the growl isn't the clutch, it's the transmission:


I'd suggest you check the flatness of the plates carefully. Notched baskets/bosses do contribute to this, but it's usually more a matter of the plates being warped, free play excessive, bad springs, or an unfriendly oil being used.

Grey, thanks for the reply. I'm running Amsoil 10w-40 in the bike. I'll go and check the flatness of the plates to see if any of them are warped. How much notching can I have on the clutch basket fingers before I need to replace it? Thanks.

One other question - I noticed when I put the clutch basket back onto the main shaft of the transmission that the large gear on the back of clutch basket did not fully engage with the primary drive gear on the crankshaft. There was only about 85-90% tooth engagment between the two. It seemed like the basket needed to slide further onto the shaft to have 100% tooth engagment. This seemed a little bit odd to me, is it normal???!

I just had to replace the basket on mine at 72 hrs. You would be surprised at how little notching it takes to hang the plates up. Keep moving the basket it will go on all the way. Make sure the thrust washer is in the right sequence. I had the same neutral issue until the clutch was adjusted correctly after the new basket and boss install. Got all the parts from the Thumper Talk OEM site.

The kick/auxiliary drive gear is probably not meshing with the kick idler or the oil pump drive gear. keep fiddling with stuff until it drops all the way in.

The kick/auxiliary drive gear is probably not meshing with the kick idler or the oil pump drive gear. keep fiddling with stuff until it drops all the way in.

Did that last night on a 08 WR 450. on that bike the oil pump idler gear had to mesh first then the kick start gear.

I watched my buddy figure it out. He gently slid a very skinny long screwdriver (a metal coat hanger would work) in between the basket and the case. With a flashlight he could see the oil pump gear and turned it with the screw driver until it meshed. The basket slid in an extra mm then was then hung on the kick start gear. we turned the kick start slowly and it fell in.

thanks for the replies, I did line up all of the gears while installing the clutch basket, I verified that it is bottoming against the bearing that holds the main shaft in place, I just thought that the primary drive gear and the gear on the back of the clutch would be 100% meshed with eachother.

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