need some help with valve clearance adjustment

[DimitriT]

I finally managed to get the 24 year old gasket off (can someone recommend a good gasket residue cleaner)

I followed the procedue for checking clearances and I am within spec on 7 of the 8 valves.

One of the exhaust valves appears to have fallen below .03mm clearance (my feeler gauges only go to .03mm).

I've ordered the tappet depressor tool from CRC2 and will take out the old shim and note the value.

So here's a question: I've read about folks swapping shims between valves to get them within spec. Is it ok to rotate the cam onto a tappet WITH NO SHIM in place? So for instance, I take out the old fat shim and decide to try swapping with a thinner shim from a different valve, but to get the thin shim out I need to rotate the cam. Will I damage the tappet without a shim on it if I do this? Or should I order a spare shim just so I can do the shell game and swap them around?

[KEITH KRAUSE]

Don't rotate the cam with no shim in place.
You can remove the shim when the cam lobe is in two positions, which may help you. Depends on what two valves you're working on.
Some people think the cam lobe has to be straight up. Some also make inaccurate measurements by insisting all the lobes point up. Always follow the factory procedure exactly. It's the quickest and simplist way.

[BRycraft]

Cam Lobe Position

According to my "factory" service manual it shows 2 different positions the cam lobes can either be in to check the gap, the upright 12 o'clock position or the 3 or 9 o'clock position depending on if it is the exhaust or intake and what side of the bike you are on. Basically the intake cam lobes can be upright in the 12 oclock upright position or facing towards the rear or carbs laying on their side with the middle of the cam lobe in line with the surface of the head or where the valve cover gasket lays. The Exhaust cam lobes can be upright also or facing the front of the bike, in either position the cam is not touching the shim.
Did you map out the size of each shim like #1 intake 2.70, #1 Exhaust 2.65 and so on...?
If so you might be able to get lucky, when any 1 cam lobe is in the position to be checked or removed or upright lets say there is always 1 other lobe in the same position. Get the cam in the correct position for the valve you are checking, then look to see what other lobe is also in the same position, if you are lucky that shim is 1 size smaller then what you have and is the size you thik you need. If #4 exhaust is your last one to check and it is lets say 2.65 hopefully the other shim that is available for removing is a 2.60 and you can swap them and see if the gap is now within tolerance and if so then that is the shim you need to order.
Or you can go to any local auto supply house or a Sears hardware and get a set of feeler gages for about $7, usually on the larger set they will go as thin as .0015in which is .0381mm, if that is too tight then most likely you need the next smaller size shim. Also I learned from someone on this forum that I was not aware of is that there are some shims with a x on them like 2.65x indicating that it is thicker then a 2.65 shim but thinner then a 2.70 shim. I did in fact find some of these already on my bike and that comes in handy because if one shim lets say 2.60 is a little too thin and the next size 2.65 is just a little too tight then if you have a 2.60X that might be all the difference you need.
Hope I didn't confuse you...

[DimitriT]

Hey thanks for the good replies. It didn't occur to me that the I can depress the tappets when the cam is in two positions. I'm just waiting for the tappet tool to come in and I will get to work and map out the current shim layout. Then I'll see if there may be some swapping options and if I can get the cam in position for an easy swap. I should've just ordered an extra shim with the tool to make the swapping easier.