GS-650 Tappet Clearances

[G0FHM]

Chris,

The closest dealer to me is circa 35 miles away, so that's a 70+ mile round trip. So there will be postage whatever happens!

I can get a pair from the US on ebay, which works out £17 the pair delivered - But then there is the waiting time!

I'll go see Shaun in the morning, see what he has - Else try and find a more local dealer!

J

[Agemax]

any UK dealer will post them to you, within a few days usually. google it and ring them all until you find one that has some in stock. if not, most dealers will get them in within a few days if ordered

[tkent02]

What I don't get is if you ground all the valves, and didn't shorten the valve stems, the shims should all be several sizes too large. You had a couple that were OK? That makes no sense.

Wait, corse and fine, and a stick?
You just lapped the valves? OK never mind.

[G0FHM]

Yes, I meant lapped!

I'm not about to start playing around with valve seat cutters... I don't have the engineering prowess to pull off such a feat!

So lapping them in will have no real effect?

If so, it reinforces my suspicions that somebody has had a go in the past and made a bit of a pigs ear of the job. That may explain why number 3 had a lower compression figure. The exaust valve wouldnt have been seating properly with the negative clearance.... I did the motor oil down the plughole test, and it raisedd the compression slightly, but not blisteringly high! like the other 3

Apologies for any typos and grammar errors, using tablet

J

[tkent02]

Yes, I meant lapped!

I'm not about to start playing around with valve seat cutters... I don't have the engineering prowess to pull off such a feat!

So lapping them in will have no real effect?

If so, it reinforces my suspicions that somebody has had a go in the past and made a bit of a pigs ear of the job. That may explain why number 3 had a lower compression figure. The exaust valve wouldnt have been seating properly with the negative clearance.... I did the motor oil down the plughole test, and it raisedd the compression slightly, but not blisteringly high! like the other 3

Apologies for any typos and grammar errors, using tablet

J

All correct except for the pignose part. Normal wear results in tighter and tighter valves, neglect them and they will get negative clearance, neglect them more and you get low or no compression on that cylinder, keep riding and burnt valves will follow.

Once they re shimmed correctly check the compression again, if you are not happy with them ride it 1,000 miles and check again.

[G0FHM]

I'm fixed up now!

Went to the local bike shop this morning and grabbed a pair for pennies and gave the unwanted ones in exchange!

Sweet

J

[Agemax]

happy days

[G0FHM]

It wasn't an easy task though....

The last rookie that he had in the workshop dropped the box on the floor, and he told him to put them back in size order....

He didn't!

[tkent02]

If you organize them for him I bet you get cheap shims for a long time!