valve adjustment assistance and shim request

[thumperjsa]

There was talk of a shim bank a while ago. Is this still happening?

I went through and checked all my valves today. I took down all the measurements and anything out of spec, I pulled the shims with the help of a little grinding down on my MP Tool I got from Bike Bandit. It too me about 3 hours from start to finish. The first two hours were spent measuring with the guage and figuiring out how to place the MP tool and grind it down a bit so it was easier to get the shims out.

So I have a few questions that I hope I can get some help with.

1) My guage which I picked up from NAPA, not only has metric and standard, it has two measurements on it that seem to be .002 inches (~.05 mm) off from each other. For example .005 inch .007 inch and .127mm .178mm are all on the same guage.

I thought it might be that one half side of the tip is one thickness and the other half of the tip is the other. That did not seem to work out so is it that the measurement of the guage is a thickness between those two points?

2) I made up a table of what I measured and what I believe I need. Can someone check this for me and let me know if what I marked the dimensions are OK and I do need the shims indicated.

intake Specs .006 -.008 .16 - .20
1 2 3 4
inch .005 -.007 .006-.008 .007-.009 .008-.010
mm .127-.178 .152-.203. .178-.229 .203-.254

1 2 3 4
have 275 OK 275 285
need 270 OK ? 290


Exhaust Specs .008 - .010 .21 - .25
1 2 3 4
inch .008-.010 .008-.010 .010-.012 .013-.015
mm .203-.254 .203-.254 .254-.305 .330-.381

1 2 3 4

have OK OK 280 285
need OK OK 285 300

3) Being that the 3rd intake is so close to spec, should I leave it alone?

4) So if I am correct, I need 3 shims. After moving the 285 shim I pulled from the #4 intake and putting it in the #3 exhaust (I am going by the stamped numbers of course), I have some I can't use and some I need.

I have a 275, 280 and 285 I don't need. I need a 270, 290 and 300. Can anyone help me out with the 3 shims I need?

Thanx in advance for assitance

[newmaac]

Thumper,no dice on the shim pool, but I think that I have those three. I will confirm that tomorrow AM when I get to work.
If I do have them, I will trade you for your old ones.

[2fast]

I just did my valve adjustment this winter. I inquired at my local yammy shop/dealer about shims. They said they would trade me one for one for whatever I needed, no charge! Might want to check your local dealer and see if they would do this for you. I helps if you have been in there before, of course.

[ratbyk]

Shims

I had the same experience as 2fast at my local Kawi dealer this past winter. Of course I buy all my tires (for 3 M/C's) and accessories from the same dealer. First name basis all round.
Ken/Sooke

[thumperjsa]

need a shim

Local dealer says they don't have the shims. I have arranged with newmaac to swap out two of them. Can anyone help me out on the third one?

Newmaac, will swap me out the 270 and 300, but he ha no 290.

Can anyone swap me out the 290?

[pggg]

Dunno but 270's, 290's, 300's seem pretty high as the usual shims are around 230 - 250. Thump are the mathematics triple checked? The popular 230 - 250's are usually scarce to swap for and the 270 - 300's usually sit in boxes unused.

[DiverRay]

I'll check my box for the 290. I have three spare shims, and If newmacc has not mailed them off yet, and I have it, I'll hand it to him Saturday.
Ray

[ratbyk]

Valve Shims

Talking about shims. The Ratbyk has moved down the road so I no longer own a Yamaha. I have a valve tool (modified so that it works) and an assortment of 8 valve shims.
First offer of $25.00 plus postage gets the whole works.
Ken/Sooke

[randy]

While we're on the subject of valve adjustment, have any of you heard of or seen this tool before? it's a Kent-Moore # ym-33296. apparently it's no longer manufactured ( according to Kent-Moore). It's got a little doohickey that pokes out when you flip the lever, supposedly pushes the bucket down so the shim can be removed. I'm going to test it next weekend, and if it does what I think it does, it will make valve adjustments a breeze. I wonder if any of our machinist guys can take a crack at reproducing it? I own this one.

[ratbyk]

Valve Tool

It looks "trick". The curved tip would likely mount under the cam lobe and the protruding tip should force the bucket down. There is not much room to manipulate tools around in there. It may prove to be to bulky to use. Also suggest that if you use it make sure the piston on that cylinder is not TDC when you force the bucket down. You could end up with a bent valve.
Ken/Sooke

[thumperjsa]

Diverray, I don't think newmaac had a chance to send them yet.

Pggg, I posted my measurements in the first post in this thread. Based on the manual and what I measured, I believe I am right. Considering I am starting with and off 1 - 3 sizes, I believe the math is right. I triple checked the measurements before I pulled the shims. I got the requirements of what I need out of the manual. The exhaust valve on number 4 had little problem getting the .013-.015 under it. That is the one that needs a 300 because it is 3 sizes off and started as a 285. That would mean this valve was not opening enough when the lobe hit it by quite a bit.

Trust me. When I get these shims in, I will be hand cranking the engine several times to make sure nothing feels or sounds funny.

[ratbyk]

Valve Clearances

Your valve clearance on #4 exhaust does sound excessive. There must be excessive wear on the cam lobe, or the tip of the valve is mushroomed over, or the valve is bent not allowing it to close to it's normal seat, or there is carbon or something between the valve face and the seat.
The only way clearances become excessive on these engines if something is wearing away. Usually clearances tighten up as the valve seats deeper into the seat.
One other possibility would be that the camshaft main caps are loose or the studs pulling out of the head.
Ken/Sooke

[thumperjsa]

Update report

Got the shims yesterday. Thanx to NewMaac and DiverRay.

I put most of them in that I got from you. For some reason, when I put the 300 in, the tolerance became way to close. The 290 worked better. So I played around a bit, Got them all close to tolerances with what I had on hand.

I made sure to hand turn the engine after every shim replaced to make sure noting was hitting. Cranked it once without plugs and then with plugs with no wires. Still all well. Put on the engine covers and put on the plug wires and what do you think happened next?

All was still OK.

So I managed to do a succesful surgery without the need for an unqualified bike shop mechanic at $70 per hour.

Took the bike out for a hour long ride. After about 10 minutes it felt like it was running on two cylinders. I know that feeling all too well. Looked under the tank and one of the fuel lines were pinched. Pulled off the seat and then up goes the tank. Re-routed the fuel hose the right way, put it all back together and I am off and running again. Glad I brought pliers with me.

Bike seems to be purring better. Idles better and actually feels a bit stronger. Before after it would warm up, it would idle at 2k and not like to come down without forcing it too by leaving it in gear at the stop light and letting out the clutch a bit. Then after pulling the clutch back in, sometimes it would keep the low idle. Now when warm, it is still idling at about 1k and I did not do anything to the carbs or adjustments.

Took her out on to I-95 at about 65 MPH. Put it in the left lane and opened the throttle a bit. Was doing 90 before I knew it and passing traffic. Did that for a couple of miles. Then brought her home. She ran like a champ.

Can't wait to test compression and see if it improved a bit. Acceleration feels a bit more like, "rip arms out of socket" so I think she is doing better, and I am happier for it.

Thanks to all on this forum for the support. Some work seems a little out of reach because most of us are nt even shade tree mechanics. There is enough friends here on line to help out, even with the minor surgeries.

[pggg]

Thump, now that's all done you can now start on the loose camcaps and studs. joking.

[jazzrat2000]

shims needed: 270, 270, 285?

Hey thumpersja, great news on the shims, I found the sheet!! So, I need to find out if anybody has the following: a 270, a 270 and a 285... I will have 2 265s and a 285 to trade, but would also consider buying the ones I need with no trade, if that is the proper protocol for this...

Also, it is great to hear your bike is up and running again, thumpersja! I am off next weekend to pick up the XS750, wish me luck!