Camshaft endplay guidelines

Are there guidelines for the amount of endplay for the camshaft once the timing sprocket is seated properly?

If a shim is required where is the best location to ensure cam lobes cover the tappets?

Tom

I can't say that I have seen a need to shim a camshaft however I suppose you could remove the shoulders from the cam bushings and replace them with custom washers to move the cam around if so desired. Jim

I think i may have left out the inside thrust washer in my Trixie Combat last month, as found a set in tray with the cam chain drive. Installed and tensioned, seems to me that chain would hold cam in line even against the slight pull of tach drive. Also had a fella tell me he forgot his shim/thrust washers inside, 35K miles ago. I pulled on cam to see it slide out further than I remember it, but will try it and see.

Like Jim, I can't see the need to shim the cam for endplay, but I do it anyway. Might not do anything good, but no harm either. Kind of like chicken soup.

I used to use thin shim washers, but got nervous about using such thin material. Now I just turn new conical spacers on the lathe to replace the stockers, and keep the end play down to .005" or so.

Ken

So are we saying that we allow end play?
I've just fitted my PW3 with the sprocket nice and tight (feels like the nut bottomed out on the thread) and I feel there is considerable end play, around 0.015". This week I will put a dial indicator to it to confirm but its about the same as the crank.
The past posts seem to mention removing shims which is confusing to me as it seems to imply that there was no end play found.
Jim, I have bought the modified drain plug and breather combo from you... so I took the OEM breather plate and spring out of the drive side bushing.. would that spring and breather reduce some of the end play?

CDubb said:

I took the OEM breather plate and spring out of the drive side bushing.. would that spring and breather reduce some of the end play?

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Well you know the answer is no....wrong end..at most your end play would be sprung!

It is not difficult to shim it anyway....I recall sourcing off the shelf shim 5 and 10 thou shims from a John Deere tractor specialist....steering box shims....they won't come to much harm...but settle for an extra 5 thou if you don't like the idea of using the 5 thou one....

And if it i so seriously out of line that you cam lobes are off the followers, I think you have another problem to address, shimming won't fix that...

As for hobot, you know you really want to strip and fit that washer don't you

200,000 series cam bushings were just a bad design...lovely hard tag just ready to break off....and they did...and with a bit of effort they could get themselves all the way to the scavenge pump...though I guess there are none of those left now...

hobot said:

I think i may have left out the inside thrust washer in my Trixie Combat last month, as found a set in tray with the cam chain drive. Installed and tensioned, seems to me that chain would hold cam in line even against the slight pull of tach drive. Also had a fella tell me he forgot his shim/thrust washers inside, 35K miles ago. I pulled on cam to see it slide out further than I remember it, but will try it and see.

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Steve,
Remove the rev-counter drive and you should be able to see if the spacer is at home.
Cash

I shim mine with a Triumph gearbox phospher bronze spacer bush on the drive side case. Perfect fit.

But I heard that the tacho gear take off drive forces the camshaft onto the thrust washer, but can't confirm.

I do think it stops the camshaft sprockets from becoming missaligned when the power is either on or off.

Just my 2 cents

Andover still supply the camshaft bushing washers with the tag on. Only they suggest these are removed before fitting..

marinecommando said:

Andover still supply the camshaft bushing washers with the tag on. Only they suggest these are removed before fitting..

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Exactly, and that advice was around even in the '70 when the bikes were new! just not from the supplier, so often those who really needed to know to do that....didn't!