Did my shims and WOW!

[GLoweVA]

Last Friday, I finally got around to doing my valve shims and WOW, I'm surprised by how much more power and response I have now.
Every one of my 8 shims needed to go down at least one size some 2 sizes.
I started the day tearing apart my SG to get the shims out of it to use.
Then I moved on to my G. Before pulling the cams out, I measured them all.
CatatonicBug had sent me a 255 because I knew I needed one, but as it turned out, I needed 2 more.
So I called up the closest Yama dealer and he said sure, we'll trade them out.
Took 2 of my 295's down there and BAM, two 255's in my hand. Turns out, they were just a hair too big.
Call the BMW dealer and he had 2 ($8) a piece!
So, got those in and put cams back in and checked all my clearances, and they are all at the top spec or just a hair over, so they should be good to go for many more years.

While I had the fairing off and enough hours left in the day, I decided to finally change out the front upper motor mounts to get rid of that nasty vibration that make my right hand go numb after 30 mins of riding.
It took a breaker bar to loosen the bolts, but they came out okay.
Here's a pic:


So my new ones didn't come with the metal insert sleeve. No problem, I'll just pull the old ones out.
Yeah, right. Those suckers were vulcanized to the rubber. It took me 3 hours to get those 2 out and cleaned up enough to use.
After all that, I got it all back together and wouldn't you know it, My 'Vibration' has gotten worse.
I guess those polyurathane bushings transmit the vibration a little more than the rubber stock ones do. Add to that the fact the my valves are a little more open now which probably adds to the engine vibes too.
Anyway, I'm glad I did the valves and the mounts, they needed it.
I'll take the trade off of a little more vibration with the increase in power and performance now.

[Yard Dogg]

I thought we had a pool of shims somewhere on here so members could send in their old ones and trade for the ones they need. Do we still have that cause I will need to shim.

[DGXSER]

Not so much on the Shim Library these days. However, alot of folks have good luck going to small shops or local dealers and getting them for under $4 or even swap.

[jjz28]

I have never checked my clearance yet, a motorcycle mechanic told me that they are recommended by yamaha to change at 26,000. Does anyone know if that is right? My bike has a little over 14 thousand on it now, so i just figured i have a lot of miles left before i check it. am i right or should i check them anyway?

[crazy steve]

Yamaha recommended checking the valves every 3K miles, but that's really too often.

At 14K miles, you should at least check them; they may be fine, they may not. The bike can run noticably smoother with properly adjusted valves. Personally, a check/adjust every 10K is what I'd do...

[Nightengale]

thanks george

I have never checked my clearance yet, a motorcycle mechanic told me that they are recommended by yamaha to change at 26,000. Does anyone know if that is right? My bike has a little over 14 thousand on it now, so i just figured i have a lot of miles left before i check it. am i right or should i check them anyway?

george helped me check my valve clearance on my bike today. my bike is an 81 h with about 36,000 miles on it. i am not sure if the PO had done anything with the bike or not, but when we checked them, they were all pretty good. with the exception of two to the exhaust valves were off, and had to change those shims. so all this to say that it wouldnt hurt to check them. the main reason i checked mine was that i had a leaky valve cover gasket, so while i had the valve cover off i figured that this would be the best time to check them. it does help to have someone close that knows what they are doing, and has done it before. thanks again george.

[petejw]

hi george,
jat, after re shimming, re sync/adjust the carbs
it might help a little with the vibrations.

[GLoweVA]

Yeah, Pete, I did do a sync. I did notice that a few were off a little from the previous sync. I expect that's due to the valves opening/closing at a little different times now.

The vibrations are most likely due to the polyurethane motor mounts that I put in. They seemed a whole lot harder than the rubber ones I pulled out.

I recommend to all who have gotten a 'new to them' bike to at least go in there and check the clearances. It's not that hard to do and it'll give you peace of mind to know that you're good to go or not.

On John's bike (nightengale) He hadn't checked his since he got his bike and we found that #2 exhaust clearance was too big by at least 2 sizes. The PO had put the wrong shim in there. Even though his bike ran fine, now it runs better.

[Nightengale]

noticed a differance

since me and george (GLoweVA) adjusted the valves in my bike, i rode the bike all day sunday and noticed that the bike felt a little different, but i couldnt tell much of a difference. that is until today when i rode my bike to work, the bike seems to be running at lower rpms at highway speeds. like most of you that ride your bikes alot i can normally tell how fast i am going depending on what gear i am in and how the engine sounds. i noticed that i was changing gears at higher speeds than normal, by about ten miles per hour form where i normally shift from 4th to 5th. not dramatic results, but we only had to adjust two of the exhaust valves. so all this to say if you havent checked your valves in a while you might be surprised with what a difference i makes.