Oil pump drive gear

06 YZ450F Oil Pump Drive Gear has a bunch of slop in it. The cogs on the gear look fine and the bike is pumping oil.

is that by design?

was this question to stupid or to complicated for anyone to answer?

Oooh! An attitude...

"A bunch of slop" is not a particularly specific description of things for one. Is the play rotational? End play? shaft clearance in the pump housing? What?


sorry didn't mean to come across as having a bad attitude. I kind of figured it was a stupid question or i didn't word it right.

The bigger gear that drives the oil pump in the engine will move in and out and just feels loose. The manual does not show a bearing or anything on the shaft of this gear. I really don't understand how it works. do you have a link I can go to to read up on the oil pump drive gear? I noticed this when i was replacing my waterpump seals using your post. (bike quit leaking from the wheep hole but still low on fluid after 30 minute ride. but that is another subject)

sorry for the attitude, people usually answer back so fast on hear it threw me when i didn't get any reply for a couple of days.

As hard to believe as it may be, I was doing something more important than ThumperTalk that whole week. :excuseme: Sorry...

So it sounds as if you're concern is with the oil pump idler gear. The oil pump is driven by the gear on the back of the clutch basket/primary driven gear assembly; the same gear used for starting the engine. That gear drives the idler gear, which drives the oil pump. The idler sits on a shaft in the right crankcase, and has a thrust washer on top only (sits directly on the case on the inboard side), followed by a snap ring retainer. It has no bearing, and it's normal for it to seem "a little loose", both in terms of the fit on the shaft, and in terms of end play. There's no spec given for it, and you'll either have to inspect for signs of visible wear, or have someone look at it if you're worried.

Thankyou sir, I think it is ok doesn't look worn at all. I rode the crap out of this bike for 4 years and the internals look bran new. I replace the top end about 2 years ago and had to reshim it one time after that because it wouldn't start. besides that this bike has worked great and I am very happy with it. first 4 stroke original owner, Yamaha for life!

Thanks for responding

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