R12 valve adjustment

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norwaybike
Posts: 39
Joined: Fri Jan 26, 2007 3:44 pm

R12 valve adjustment

Post by norwaybike »

I think the valve adjustment procedure on my R12 is difficult. I have adapted my tools to try enter the nuts better, but it will not be as I wish. Do some of you have any good tips, procedures or tricks to make this job easier?

Bigsieuk
Posts: 106
Joined: Mon Feb 27, 2012 7:40 am

valve adjustment

Post by Bigsieuk »

There are a number of ways posted here. As space is so tight when the valves are closed, I usually check the gap when the valve is closed, then rotate the engine and adjust when the valve is open as it gives more space and then check again when the valve is closed. It can take an number of tries to get it correct but its easier than trying to get the spanners in the small space.

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mdunn
Posts: 86
Joined: Thu Feb 21, 2008 1:00 pm

R12 valve tools

Post by mdunn »

Having the right tools makes it easier but its still a bitch. One of the most lame designs ever for BMW if you ask me.

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Bruce Frey
Posts: 536
Joined: Fri Oct 27, 2006 3:00 am

I generally do it as Bigsieuk

Post by Bruce Frey »

I generally do it as Bigsieuk does. If you measure the gap and know how much adjustment is needed, you can calculate how far to turn the adjuster by knowing the thread pitch (I have forgotten what it is, however). e.g.,if the thread pitch is 1.0mm, then 1/4 turn is 0.25mm. It will probably take a couple of tries, but it works.

Fabricating a set of tools that fit is really, really helpful.

Bruce


Bigsieuk
Posts: 106
Joined: Mon Feb 27, 2012 7:40 am

spanners

Post by Bigsieuk »

Mike,

Does anyone sell those types of spanners?

Regards

John

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mdunn
Posts: 86
Joined: Thu Feb 21, 2008 1:00 pm

John, NO, unfortunately not.

Post by mdunn »

John,

NO, unfortunately not. I have a casting to make them and I plan on it soon.

Mike

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mdunn
Posts: 86
Joined: Thu Feb 21, 2008 1:00 pm

John,NO, unfortunately not.

Post by mdunn »

John,

In time I will have them....

Beemer54
Posts: 62
Joined: Sun Sep 07, 2014 1:07 pm

I picked up a set on Ebay

Post by Beemer54 »

I picked up a set on Ebay about a year ago. As Mike says - they help a bit but it's still a ridiculously fiddly job - they're still too thick. Your way works better.
My final solution was to nag friends to look in their rubbish drawers to see if they'd got any of those awful, thin multi-spanners that tend to come with new lawnmowers, strimmers and the like. I was able to cut these up and bend them to the correct shape. Because they're so thin they make life much easier. They wouldn't be suitable for anything that was really tight but they're perfectly adequate to tighten tappets.

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Bruce Frey
Posts: 536
Joined: Fri Oct 27, 2006 3:00 am

Bicycle tools also make a

Post by Bruce Frey »

Bicycle tools also make a good starting point. Thin and relatively inexpensive.

Bruce

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Darryl.Richman
Posts: 2087
Joined: Fri Oct 27, 2006 3:00 am

As Bruce says, you can buy

Post by Darryl.Richman »

As Bruce says, you can buy "spindle" or "hub" wrenches at a bicycle shop. They are stamped steel, but strong enough to lock the adjustment. You will have to grind material off them before they will fit, and you can bend them with a propane torch and a vise or vise grips.

As everyone here has confirmed, adjusting the valves is a PITA no matter how you try. I've run my R52 on the Cannonball a couple times now and had to adjust valves on the side of the road.

I've tried both methods, and both are slow and annoying. If you don't have the right tools, you can really only do it by measuring with the valves closed and adjusting with the valves open. With usable tools, I think it can be done a bit quicker with the valves always closed.

BMW could have easily designed this so it could be done easily with regular tools. ~X(
--Darryl Richman

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