Need shims bigger than 3.50.

[Randle]

Hi all,
I am working on a ZXR400 that requires some valve shims bigger than 3.50mm.
It seems genuine Kawasaki shims stop at 3.50mm and the only aftermarket ones I have found (Hotcams) also stop at 3.50mm.
Anybody got an idea where I can get some shims around 3.55mm and 3.60mm?
Diameter is 7.48mm.

Other than that the restoration is going well.......The bike is not mine, but I had to ride it for 100 miles the other night, starting with the motorways around Liverpool, in the dark, in the pouring rain, 2 up!
Brake lever nearly coming back to the bar, clutch lever that didn't want to come back to the bar, it was so stiff. Exhaust rusted through and blowing!
The bike was desperate for a full service......so here I am.......there's a good bike in there somewhere.....

[RedexRobB]

If you need to go that large surely theres something wrong?

[Randle]

Well possibly.....I will have to take another look at the valve parts with that in mind. I only discovered today that I could not get big enough shims and realized the extent of the problem.
The previous keeper had receipts for new rocker arms, so I had assumed that possibly these had worn during their bedding in.
There are some large clearances I have found in this engine.
The manual says top spec on exhaust clearance, 0.21mm.
The clearance between shim and rocker arm in this engine, 0.32mm.(Edit: I mean clearance between rocker and cam)
All 16 clearances are out of specification! All but one are loose not tight.

When doing the strip down I did not notice any excessive damage/scoring to any of the valve train parts. But the mileage is high at 51000KM's

[RedexRobB]

thats not massively high mileage but if they are the original cams and followers i guess its possible they have worn way beyond spec. Have you checked the microfiche to make sure all the parts are there?

[Randle]

I think everything is there. I will try to get some pictures of the parts. Maybe you will recognize some wear.
One thing I had wondered about......I believe the cam timing was actually wrong on this bike. It appeared to be one tooth out.
That would place the cams at a slightly different position where the measurements are taken with the feeler gauges.
Maybe, with the cams in the correct position, the clearances would not be so large. I don't think it would make much difference though......
I may put the cams back in, time it correctly and check again........I have a new cam chain coming, that will change the timing also.....best wait for that to arrive.
It looked like the tensioner was at the end of its travel. The rod all the way out to the casing.

[Randle]

Pictures of the cam parts....... Nothing was missing as far as I can tell. I have taken all shims out.

'New' rocker arms look ok. Move up and down nicely.....I must check the point where they touch the shim though....

What the hell is all that welding!. That alarmed me when I saw it. However it appears to be ok. Not a load bearing part or bearing surface. I need to check the oil feedway has not been blocked inside.

Why didn't they just buy a replacement part when they broke it??

Bearing surfaces in the camshaft caps appear a little worn, but not excessive.

That big shim is not a shim, it is a battery from my vernier calipers! ha. It will not be going in the engine.

The oil feedway seemed to have oil in it on each bearing surface, suggesting it has been getting oil.

Camshafts look fine.

I would say hardly any wear at all.

Any thoughts?

Hope I haven't overdone it with the pictures.......

[cargo]

you could try measuring the valve clearance in the right place

[Randle]

Oh, bloody hell!!!! I think I measured between the rocker and the cam......should I have measured between the rocker and shim????

[Randle]

No. Manual says measure between rocker and cam.....hhmmmm.....thats what I did.

[cargo]

According to your second post in this thread you measured between rocker and shim

[Randle]

Yeah, sorry. Thought process/typing error.....maybe I can edit that post?......shows you were paying attention though. Gold star for you, and I must try harder. Ha...cheers.
I definitely measured between rocker and cam.
My plan is to fit the new camchain, when it arrives, then recheck all clearances in case things have altered slightly. It may be just enough to help, but I am not expecting much change, if any.

[zimm]

one version of the manual says between rocker and shim, other version says between rocker and cam ..

so really .. both are right ..

hasnt got reground cams (kent) in has it ?

they take a bit off the base circle during the regrind necessitating larger than normal shims

[Randle]

Standard cams as far as I know.
The previous owner was a regular road rider, not racer.
Is there a way to recognize reground cams?

[zimm]

measure the lobes etc .. standard specs are in the H model manual iirc

its possible they were acquired cheap and just thrown in without setting clearances ?

[zimm]

looking at the pics though ... the cam journals are slotted.. stock cams arent .. its an "F3" mod,

check out pages 7 and 8 of the zxr400r (racing) manual (http://www.zxrworld.co.uk/Manuals/zxr400r.pdf) and you'll see what i mean

recommended valve clearances in the same manual are 0.25 inlet and 0.28 exhaust, its increased to allow for the extra thermal expansion likely in a race engine .. does make 'em clattery as fsck when cold though.

so, possible they are re-ground and possible they were just set up on the loose side... probs when that cam cap snapped and was welded up.. maybe the oil starvation ate the original cams ?

(they're easy to break btw, if you dont ensure 100% that its sat down nice on the dowel when tightening its just *crack* -- bugger ..)