Is it OK to............

remove all shims that need changing at once? As you can tell I have never
changed shims on a bike. All my previous four strokes have been SOB's with
tattering chappets. I need to know that it would be OK to hoik out a shim
then turn the engine for the next one etc and that the cam running directly
on the bucket won't damage it at all.

 

Yeah, that's fine. I mean, a cam lobe wiping a bucket at whatever speed
your hand can turn over an engine isn't going to do any harm at all.

However, if you're hoicking out a shim, better to replace it
immediately, IMHO, otherwise you run the risk of forgetting which shim
was atop which valve, and making a hash of the clearances.

Measure gap, if necessary remove shim, calculate thickness required for
new shim, insert new shim, move onto the next one. That's the best way.

 

I find that drawing a nice picture, or making up a nice little table on
a bit of paper is best. You want cylinder number, in or ex valve actual
clearance, shim size and target clearance.

I dunno if the dealer will let you have the needed shims on the strength
of you bringing the old ones back. Maybe it's best keeping some old
shims so you don't have to gamble on the top of the empty shim bucket
knackering the cam lobe if it's turned with no shim in there... and as
Tog says, you don't want to muddle them up.

 

That's exactly what I do.

Few dealers exchange shims these days. I keep old ones, because you
often need them. Big ones can have their size inked on with indelible
marker.

 

Shims can be as much as £10 each, so one dealer told me.. dunno how true
this is though. I've always been able to exchange them at about £3 each.

As do the little ones in my FZR. Although it's not hard to measure with
a micrometer, just to double check.

 

Just thought it might be better this way as I am twenty miles away from the
nearest bike shop and don't have any shims. Just thought it would be easier
to take them out, see what size I need and go buy or exchange them. This is
my understanding of how to get shims but having never had to do it
before......

 

My Ducati ones vary - different price for opening or closing, and I
unremember which. But one is about 4 quid and the other twice as much.

True.

 

Yes, I se the prob, but once you've taken one out and checked it, you
can work out what size you need. If it's a matter of just two or three
shims, as long as you make damn sure you know which shim came from which
valve, you ought to be OK, yes.

 

gazzafield wrote

Spot on, well done.

 

Especially when you have a large plastic flip lid tray with ALL the shim's
and their sizes neatly marked out in little compartments.

 

Not a problem. Just re-check the clearance after you have changed the
shims.

 

Don't forget 'L' or 'R' if it's a four-valve...

 

Yeh, I use W and A on the FZR, no ambiguity as W is for water pump and A
is for alternator.

 

It was somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember
(The Older Gentleman) saying
something like:

On the ol GSs it slightly knocks the edge of the cam lobe against the
bucket edge and just ever so slightly bevels the lobe edge... even at
hand speed.

 

OK, I stand corrected.

 

It was somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember
(The Older Gentleman) saying
something like:

I stood aghast. After that I put a 2p piece in as a temp shim for turn
over purposes.

 

Did it work, or did it just scratch the load bearing part of the cam?

 

Excellent, thought so, but wasn't sure that the coins were 100% copper.

 

Using the patented Mavis Beacon "Hunt&Peck" Technique, Muck

They're not.

--
Wicked Uncle Nigel - Manufacturer of the "Champion-105" range of rearsets

WS* GHPOTHUF#24 APOSTLE#14 DLC#1 COFF#20 BOTAFOT#150 HYPO#0(KoTL) IbW#41
ZZR1100, Enfield 500 Curry House Racer "The Basmati Rice Burner",
Honda GL1000K2 (On its hols) Kawasaki ZN1300 Voyager "Oh, Oh, It's so big"

 

It was somewhere around Barstow, on the edge of the desert, when the

They're not, but the thickness of the coating is enough.

Steel core with a copper (or cupro-nickel) cover.