R1100RS Valve Timing Help!

Bike in question is my '94 R1100RS - the "original oilhead." I'll have more pictures to post in my "main" thread on rebuilding Clifford's engine shortly, but I need help with a specific question. I'm not sure I have the valve timing right - setting the cam sprocket in the heads to the correct position. Here's the issue (All text from a BMW factory repair manual):

Manual says: "Right Cylinder at TDC on ignition stroke." Got it - marks on the crankshaft and the auxiliary shaft chainwheel are aligned just like the manual says - crankshaft at bottom, aux shaft at top. Flywheel has the pin thru the hole into the engine block. So that's all good.

Manual says: "Locating pin on right camshaft sprocket points downwards." Yep, no problem.

Manual says: "Mark (R or arrow) and the tip of tooth on right camshaft sprocket is precisely aligned with mark on timing gear carrier." Now here's the problem..... With the locating pin pointing down, the arrow on the left side of the cam sprocket points BETWEEN two teeth, not directly in line with one, like the manual shows. And with the locating pin pointing as straight down as I can eyeball it and the sprocket engaged in the chain, the tooth above the mark is lined up with the mark on the timing gear carrier. It looks like this:



When I spin the crankshaft 360 degrees, which spins the aux shaft 180, I should be ready to do the same thing with the left cam sprocket. The manual calls for the locating pin to be pointing up - which it is. So I end up with the tooth below the mark lined up on that side. Here's a pic of that side, at TDC on the ignition stroke:



The markings on the two sprockets are identical, so there's no right and left ones to get mixed up. I've V-E-R-Y carefully turned the engine thru by hand, and nothing is hitting or going "clunk" at TDC. But we all know things can be different spinning at 4000 rpm. So, do I have it right, or am I off by one tooth? Anybody want to go look at their bike and tell me how the sprockets are timed?

I've had the same problem. I don't think the arrow is an even # of degrees from the detent in the shaft. What I would do is put it together (chains/sprockets) and then carefully turn the engine over by hand from the front crankshaft pulley bolt. If you feel any resistance/obstruction you have a problem. If not you are OK.

I don't have any experiance with the motorcycle in question, but on my 96 RT (made in 02/95) the arows are exactly horizontal (level in other words) when aligned properly with the OT timing mark to adjust the valves.

From what you posted, it sounds like you are rebuilding yours. If so, I'd definitely want another opinion on how the adjustment should occur as I've always understoos all oilhead engines of the same series to operate the same. To me, yours looks wrong.

I do have a Chilton manual I could try and look up the information in if you want. I think it covers the 94RS.

Is this the timing information you are setting up the bike from?

Andy - Yes, that's the same info I have in the BMW factory manual. The frustrating thing is that the arrow points to a "valley" in the sprocket, rather than to a tooth. So it doesn't match the manual, regardless of how I line up the chain.

Talking with Anton, I'm pretty certain that I've done the correct things with the keyways and with the sprocket teeth. I can turn the engine over by hand with no "expensive noises" or resistance at TDC. So I think I'm OK. But any confirmation I can get would be VERY reassuring.

Camshaft lobe centers or degeeing cams is so over-looked, even by most factories. Google either of the above terms and read.

Factory timing marks for most any engine are close but never spot on.

PGlaves said:

I've had the same problem.

Click to expand...

Hey, Paul, aren't you supposed to be riding in Alaska?

Thanks!!!

Those were the tips I needed. Got her all back together, spun the rear wheel - no intference. Thanks again!