What's the best way to "adjust" valves with no clearance?

[blue83ranger]

I'm working on a '79 XS1100 standard and it's very hard to start when it's cold. So i checked the valve clearances and all of the intakes are to tight and aren't actually closing all the way. So i need to know the cheapest way to get them corrected. Meaning i don't know how open they are so i don't know how much thinner shims i need. Should i just buy a shim kit for $130ish off ebay and just try thinner ones till i'm good? or is there a simpler and cheaper way to do it? thanks for any help.

[James England]

I wouldn't buy a kit as you'll find most of them unsuitable. I would look for thin shims individually at first. They tend to be rarer than the thick ones though.

Your first step is to measure all valve clearances (ie the exhaust, since you can't get a reading on the inlets). Then make a valve chart and remove all shims, noting the thickness of each (etched underneath the shim). If you have any thin ones (eg 250, 255) on the exhaust valves, try slipping one into each inlet and see if you can get a fix on the thickness of shim required for the inlets.

By mixing and matching between valves, you may find that you only need to buy a few shims

[blue83ranger]

that sounds like a good plan to me. thanks

[crazy steve]

Let me ask you this... how does it run once it does start? If you're getting backfire through the carbs, then your clearance is below .001". No backfire, the clearance is probably a bit under .002". Hopefully you don't have burned valves, as an adjustment won't cure that... Do try to verify how much clearance there is (I doubt it's less than zero, the bike likely wouldn't run) even if it's only .001". If you have any less than zero, you may have to change those shims a couple of times to get it right.

You'll need to go at least two sizes thinner, maybe three if they're that tight. As to what sizes you'll need, there's no way of knowing that until you find out what's in there. As James said, buying one of those 'kits' off eBay probably won't have what you need. Instead, call around to your local metric bike dealers or indy shops and see if they sell/exchange used shims. These were also used on the KZ1000 Kaws, so you aren't stuck with Yamaha-specific parts. If you call a dealer, ask the service department about shims (not parts); many will be happy to fix you up.

This is a good candidate for using this method for valve adjustment:
http://www.xs11.com/forum/showthread.php?t=35434
Gives you access to all the shims at once, you might be able to shuffle some around...

[blue83ranger]

It runs pretty good. It backfires through at least 1 carb maybe 2 and it's somewhat rare that it does at all.

[crazy steve]

Your clearances are probably a bit below .002" in that case, so you'd need 3 sizes thinner to get back into spec (.006-.008"). Each shim size change is .002", so it's easy to figure....

[blue83ranger]

I checked all the valves with a better feeler gauge, the one i was using only went down to .005, here's what the clearances are. Starting with the exhaust side on the left side of the bike .008 .006 .002 .007 and the intakes on the left side .004 .002 .002 .003 and when i put the number 1 cylinder at TDC before i take the cams out, for the cam alignment do i just align the center puch marks on the left side of the cam and do the sprockets have nothing to do with it? I ask because i mainly work on offroad stuff and there's always some type of mark on the sprocket and not the cam.

[crazy steve]

You align the marks on the cams with the arrows on the cam caps when the timing pointer is at TDC. You do have to pay attention to the sprockets to make sure you don't get those 180 degrees out; all that is shown in the link I posted.

As far as shim sizes, where do you want to 'hit' in the adjustment range? Spec is .008-.010" on the exhaust, .006-.008" on the intakes. Going to the 'low' side will give a quieter motor, but you'll be doing another valve adjustment sooner. I'll also note that Yamaha reduced the intake clearances on the '80-up bikes (for noise reduction) to .004-.006", you can adjust to this spec on the early motors if you want, your call. Each shim size difference changes clearance by .002".

For a 'high side' adjustment, you'll need:

Starting with the exhaust side on the left side of the bike .008 .006 .002 .007
(in order) one size thinner, two sizes thinner, four sizes thinner, and one size thinner. For a 'low side' adjustment, go one size thicker than noted unless it's just under the spec (like the one at .007"; you'll still have to go one size thinner). This will put you at .010" for the first three and .009" for the last one.

The intakes on the left side .004 .002 .002 .003, again in order, two sizes thinner, three sizes, three sizes, two sizes.

You won't know what sizes you need until you get yours out; if the intake with .004" clearance has a 280 shim for example, you'll need a 270 shim (passing by the intermediate 275 size).

I personally like to run my valves 'high' or 'loose'; this gives the valves more time on the seat and aids in cooling them, as well as extending the adjustment interval. I don't mind the noise and they're not really that much noisier...

[blue83ranger]

I must have missed the link i'll go check that out and I would like to have them on the loose side too.
I did get all the shims out. The exhaust's on the left side of the bike in order are 280 Y285 Y285 Y300 and the intakes on the left side in order are Y245 255A Y255 250A

[crazy steve]

...The exhaust's on the left side of the bike in order are 280 Y285 Y285 Y300 and the intakes on the left side in order are Y245 255A Y255 250A

So the shims you need will be (in the same order as above)...

Exhaust: 275, 275, 265, 295
Intake: 235, 240, 240, 240

A bit of a bummer, as not one of your existing shims will be right... If a local dealer will exchange shims, trade in all the exhaust shims but hang onto the intake shims as you could possibly use those at a later date.

[blue83ranger]

I will check with some dealers and see what i come up with. Thanks for you help.

[bikerphil]

On line shim supplier, ours use 29mm...

http://www.newmotorcycleparts.com/mo...lve_shims.html

[blue83ranger]

thanks for the link. I have one dealer in particular i want to check with first but i have a feeling i'll order them from you link.

[Cobia]

Your best chance at exchanging them is to find a mom and pop type shop that's been around for a long time and talk to them. I have one near where I live and have exchanged some at times. They also have carb parts like those little washers and o-rings at the bottom of the idle jets. Don't have to buy a whole kit to replace a little part here and there.

[blue83ranger]

i ordered the shims from the link. A few sizes were back ordered but they still came pretty quick. I got everything back together and the clearances were all good. I got it started today and it started alot better but still not the greatest but i had my hand by the choke and the closest carb to the lever back fired (because it was lean) and i noticed when it did i felt air on my hand and the plug that covers the end of the throttle shaft was gone. So i pluged it up and it seems to start and run better. But i'll know for sure tomorrow morning when its all cooled down. Just off topic, besides the return spring on the throttle is there any special way to get the throttle to return to idle on it's own?