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jrapose
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VBMWMO #8617
Joined: 02/12/2007
Posts: 263

Last night while removing the barrels on my R69S I noticed what I think is excessive cam follower play.... I pulled the follower forward just enough to get my fingers on it....and rocked it back and fourth.... felt like .003" or .004" side play.... I think it should be in the range of .0006" side play...

Possibly standard followers in block with oversize bores ? I don't have any ball gauges so any ideas how to check the clearance?

The engine has 40,000 miles on it, and 72.92 pistons so it has been rebuilt (I think) once. (the pistons are loose in the bore)

Joel
Chester Ca.
1967 R69S

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jrapose
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VBMWMO #8617
Joined: 02/12/2007
Posts: 263
idea, what ya think

OK, I just went out and looked at it more..... I think I will measure the lifter as close as I can, then wrap scotch tape around it until it is .004 thick....then see if it fits back into the bore... I think tape is about .002" thick...so is newspaper but that may be too soft.

I am afraid to try to use a feeler gauge as I can't get an accurate reading ...just not enough room in there... guess I could take a piece of stainless steel wire that I have and hammer it down to .004" (I live in a really remote place in California and we are limited to what is available in town......upside...no traffic lights..elevators..big box stores...

Joel
Chester Ca.
1967 R69S

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Joel Rapose
Powerdynamo Importer USA
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jrapose
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VBMWMO #8617
Joined: 02/12/2007
Posts: 263
Diden't work

I measured the followers and then added a single wrap of scotch take and measured again + .005" NONE would not fit back into the follower bore... so I removed all but a very narrow strip...0025" still would not go into the bore...
Lastly I cleaned the followers well,. then pushed them back into the bore....then tried to wiggle it with a rounded off screwdriver.... no play other than oil clearance... and that was minimal.... so I guess my method of pulling them half way out and wiggling them is not a good test of clearance.... (works fine on car engines) no cam wear on the bottoms either...(where they usually pit)..

I guess they are fine.... but I am the type person who worries about things like that... (if you work on BMW early bikes, You are too)

Joel
Chester Ca.

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Joel Rapose
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malmac
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VBMWMO #8751
Toowoomba, Australia
Joined: 06/29/2014
Posts: 285
Joel Interesting thought re

Joel

Interesting thought re the correct tolerance.

In my copy of the workshop manual, specifications - Tappets (Valve Lifters) and Valves section it states,
"Diameteral clearance of tappets .02-.04mm (.0008" - .0016")

I have not measured that clearance yet on my machine, but will use an internal mic and an external mic to calculate.

Mal

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mal - R69s
Toowoomba- Australia

jrapose
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VBMWMO #8617
Joined: 02/12/2007
Posts: 263
How about nickel plating or hard chrome ?

I think those are what I was thinking about for clearances....and mine are much more, I am hesitant to put oversize lifters in ..... the next person that overhauls the motor won't know and might put in stock lifters...so I am thinking... what about having them nickel plated or hard chrome plated.... that should take up a thousandth fairly easy, plus give the lifter a nice finish,,,

Ideas?

Joel

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Joel Rapose
Powerdynamo Importer USA
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