Forum bmwbike.com

How can I verify that my camshaft is set to the right position in relation to the crankshaft? The repair manual shows a picture (see below) of the alignment at O.T. marked with a line on the camshaft sprocket. This line is apparently not a marking that has been made at the factory. At last my bike doesn't have it, yet I would like to verify the position.

The only markers that I have on the camshaft sprocket are the lobe on the Camshaft, the two boreholes through which one can access the screws underneath the sprockets, and the small borehole which is holding the lobe on the venting disk sitting on the sprocket.

Taking these 4 markers, what position should they be in at O.T.?

Stephan,

If you go to the Vechtech page www.greatanswers.com/vintagebmw/vechtech.htm
He has a simple method on how to set the cam timing in relation to the crank for the R27 and for that matterI I believe all singles.

Ben

Ben,

Thanks for the tip. I did look up Vech's site, and this is what it says:

quote
1. Get a bottle of liquid paper.
2. With the cam out of the block, eyeball down the cam on each lobe, and paint a white line on the face of the gear where the center of each lobe is. That will give you two marks, roughly at 4 o'clock and 8 o'clock on the gear. Then, make a third mark at 12 o'clock in relation to the two marks you made previously.
3. When you install the cam, have the crank at TDC, and set the cam so the 12 o'clock mark is directly in line with the lifter towers and pushrod tubes.
unquote

This method implies that that you actually start with the camshaft already out. What I was hoping for is to find a way to verify the position without having to take out the camshaft first. For instance by enumerating the teeth on the sprocket to identify the position where the marker line should be (as shown in the picture I posted).

Even so, Vech's method sounds somewhat unprecise (lobe marks being at 'approximately' 4 and 8 o'clock...). I would assume that getting the position wrong by one thooth will already have a negative effect on the performance of the engine.

Stephan

Stephan

I've scanned a page from the BMW workshop manual on how they suggest you set up the timing. Any more accuracy than this and you must use a degree wheel and dial gauge.
If you can give me your e-mail address I'll send it to you.

Ben

Ben,

My e-mail address is

stephs@ibm.net

Thanks!

Stephan