Need valve shim info for Yamaha F75-100

[speed_demon]

I'm having a hard time finding a shim kit for my 1999 Yamaha F100. Anyone know where to buy one? I was hoping they would be 7.48 or 9.48mm but they are larger shim over buckets. I'll pay the dealer $15 a piece if I have to but in my experience it becomes a back and forth nightmare if you don't have a plethora of shims to get the job just right in one sitting. Please help or I may resort to sanding.

 

[speed_demon]

Re: Need valve shim info for Yamaha F75-100

Got it apart today and measured the shims. Standard 25mm Yamaha/Honda valve shims. K&L offers kits but they are in .05mm increments while factory shims run in .025mm increments.

 

[speed_demon]

Re: Need valve shim info for Yamaha F75-100

Still have a few questions. I ended up with about .12mm intake and .18mm exhaust clearance across the board. The manual specifies .20mm intake and .34mm exhaust +/- .03mm which means I'm way off but consistent. The manual specified clearance seems excessive but then again I only have experience with motorcycle valve adjustments. I called three different dealers about replacement shims and they said they don't stock shims because they never see motors needing an adjustment. All three dealers agreed the specs were excessive but my manual is correct. I don't want to put it back together out of spec and burn a valve down the road. The motor runs great and I was told it only has 530 total hours. My common sense is telling me to go with .15/.25mm but I want to do it right and be done with it. Any help is greatly appreciated!

 

[99yam40]

Re: Need valve shim info for Yamaha F75-100

What did you do to this motor that this needs to be addressed?

 

[Capt Ken]

Re: Need valve shim info for Yamaha F75-100

Nowhere near time to check the valves so what is up with that?

 

[speed_demon]

Re: Need valve shim info for Yamaha F75-100

I bought it as a fixer upper a few years ago when the oil pump drive splines failed. I'm just now getting it back together and I figured I go ahead and do a valve adjustment while I'm replacing the timing belt. The manual calls for a valve clearance inspection at 500 hours.

 

[Silvertip]

Re: Need valve shim info for Yamaha F75-100

So you did or did not have the valve train apart? And whether you did or didn't. are you certain you had the cams on the base circle when taking the measurements? Hard to believe the factory setup would be that far out of spec.

 

[speed_demon]

Re: Need valve shim info for Yamaha F75-100

As far as I know the valve train had never been apart until after my inspection. I started at #1 TDC and rotated the crank 360 for the rest.

 

[Silvertip]

Re: Need valve shim info for Yamaha F75-100

As far as I know the valve train had never been apart until after my inspection. I started at #1 TDC and rotated the crank 360 for the rest.

Why did you do that? At TDC the valves will be closed. Since the cam runs at 1/2 crankshaft speed you turned the cam to something other than valves closed position and hence the lobes were not on the base circle. I'm certainly not a Yamaha expert so if you followed the service manual then Yamaha has a reason to do it that way. But one can generally turn the engine so the cam lobe points 180 degrees from the bucket. Measure the gap.

 

[speed_demon]

Re: Need valve shim info for Yamaha F75-100

I did exactly what the manual specified. Set #1 to TDC to check 1/2 intake and 1/3 exhaust, and rotated crank 360 (cams 180) to check the rest. I understand setting the lobes exactly 180 from the valves is a good way but in this case I decided to follow the manual.

 

[clanton]

Re: Need valve shim info for Yamaha F75-100

You using a factory or aftermarket manual? Specs seem a little excessive. The Yamaha motorcycle shops may have the same shim, still pricey.