Padding under old valve shim to thicken it?

[Guest]

Hi guys.

I am building a friend's Suzuki gs500 top end engine and the job is almost finished. The only thing that remains is that I ordered a set of new valve bucket shims and the guy who re-fitted the valve seats, made the valves a bit shorter so now when I fit in my shims on top of the buckets and put the cam back in, there is 0.08mm gap on the intake side and 0.1mm on the exhaust side. This is out of suzuki's specs (0.001-0.003 inch). Can I just put a little evenly spread padding of my old 0.03mm feeler gauge under all 4 shims to make them a little tight? Since from the look of it, the shims are not going to come out on their own once they are fitted in as long as I take the cam out and take the shims out, or use a shim removal tool. Will this padding be a good remedy? If not, what alternatives do I have other than ordering a new set? It takes a good 2-3 weeks before orders arrive on my place from ebay so I am figuring out a way to use what's available instead of delaying the project further.
Please advise

[Spiff]

to remove the shims when the cam is installed you need a valve shim tool, it's pretty cheap.
Since the valves on a motorcycle have a tendency to tighten up with time it's wise to have the valve clearances a little bit on the loose side, leave your intake side like it is and go the next size on the exhaust side to get them within spec. Or leave as is, 0.1 is only 0.02mm above spec and I think you'll be fine, at least that is what I have read here...
Personally I wouldn't feel safe having small pieces of feeler gauge in my motor, you never know if it will come loose and what damage that will do.

[safwan.khan]

Thanks for the reply Spiff. I would like to leave it as it is but I am hearing an annoying valve ticking sound due to these increased gaps. I also read on a suzuki forum that if the valves are left too loose above specs, it can not only damage the shims but also damage the cam lobes in the long run. So that is the main reason behind my concern. Regarding the pieces of feeler gauge damaging the engine, I do not think they will ever come out unless the shim is automatically removed from its place while the engine is running which never happens as far as I can see from the shim/bucket adjustments. Please correct me if I am wrong.

[cowboyup3371]

Those specs are just fine if it is at the mm listing you give as the specs are .03mm to .08mm (don't get the standard and metric confused). And if you are that concerned, you just need a thicker shim not any foreign body in there; just don't run it too tight or you'll burn up the valves.

[Gold01ca]

Don't do a mickey mouse job, put in the right shim and be done with it.

Cheers!

[Steve]

I also read on a suzuki forum that if the valves are left too loose above specs, it can not only damage the shims but also damage the cam lobes in the long run.

Well guess what. You are on another Suzuki forum now, and this forum is telling you that those clearances are just fine. In fact, some of us will intentionally set our clearances there.

You are willing to believe another forum, but not this one? Not a real confidence-inspiring statement around here.

.

[tkent02]

.1mm is just fine, most of us use .1mm. Tappy valves are happy valves.

I certainly wouldn't add any loose pieces of metal inside my engine.

[robertbarr]

You are willing to believe another forum, but not this one?

That's because he's almost certainly a troll.

[tkent02]

Yeah, they don't even have 500 cc bikes in Pakistan.

[Flyboy]

I do not think they will ever come out unless the shim is automatically removed from its place while the engine is running which never happens as far as I can see from the shim/bucket adjustments. Please correct me if I am wrong.

You are indeed wrong, I have thrown a shim on a GS550 motor, left a nice hole in the valve cover as it exited the motor, never to be seen again.
Consider yourself corrected.

Ok, so the little mill was spinning at around 12500rpm at the time.

[tkent02]

Ok, so the little mill was spinning at around 12500rpm at the time.

You must have got one built on a Wednesday.

[Allie]

That's because he's almost certainly a troll.

Ask him how he plans to get the engine back in the frame...

[safwan.khan]

Thanks for the response guys. First off, I am certainly not a troll!
Secondly, I got this bike from an auction and it is REAL. I'll shortly post a few pictures to make you guys believe me.

[safwan.khan]

That's a relief! So I do not have to worry about re-adjustment.

.1mm is just fine, most of us use .1mm. Tappy valves are happy valves.

I certainly wouldn't add any loose pieces of metal inside my engine.

[safwan.khan]

I did not take the engine out. Just opened the top end while the engine was still in place. There is enough room at the top to safely pull the top end out without taking the whole engine out of the frame.

Ask him how he plans to get the engine back in the frame...