BMW R1200R R1150R/T F800 K1200R R1100R/T R1250R RnineT Message Board

Suppose one were attempting to remove the rubber cap which plugs the timing viewing hole in preparation for finding "top dead center" for a valve adjust. Now suppose that upon replacing the rubber cap, it collapses and falls into the hole and thus into the engine compartment with no chance of retrieval. Can anyone imagine something like that happening....well....let's just say it did. Aside from needing a new cap, what is going to happen to the one that fell into the timing hole and what would my next move be? I'm thinking it will be shredded to little bits, but what happens the little bits. Help please!

No problem.
It'll fall to or be thrown to the bottom of the bellhousing. Even if the wind generated by the spinning pressure plate whips it around until the rubber is nothing but black dust, it won't harm anything and the powder will eventually exit out a drain hole.

Get the bigger/fatter plug from BMW.
p/n 11-11-1-744-327

The knowledge on this board baffles me and I just can't keep up.

Thanks CycleRob for the input and the new/improved part number. That was a sick feeling seeing that plug fall INSIDE the engine until I started thinking it fell into a bit of a void space in the engine. Your comments relieved my anxiety and visions of tearing down the engine to get to a stranded rubber stopper. I too appreciate the knowledge base on this board.

Did the exact same thing on my last valve adj. too. I'm sure many others have as well. About 3k miles and no problem so far. Replace it with the above referenced plug you will be fine.

I've got at least two of those little buggers roaming around in the bottom of mine. And they've been in there for at least 20k miles. No harm done, so far. Get the fatter plug, it works better.

Or just don't take it off. You can use the TDC mark on the timing chain (I think that's what it's called) next to the valves for reference.

Or just don't take it off. You can use the TDC mark on the timing chain (I think that's what it's called) next to the valves for reference.

Yes you can. But I must issue a warning at this point. Those little timing chain window covers will get warped or something and begin to leak oil if you're not careful. I used that method up until about a year ago I guess. I couldn't stop my oil leak with just new o-rings. I eventually replaced the plastic covers with those aluminum ones. Now they don't leak at all and I take the time to pull off the alternator belt cover and use the timing hole method.

Just one guy's method over another, but if you start to have a leak down there, that's the culprit most likely.

Phil - I think we must be talking about two different things. I'm referring to the cam sprocket ( I mistakingly called it a timing chain ) next to the valves. There is an arrow (circled in red) - when it points straight out as shown, you have TDC on that set of valves.



BTW, this is a photo from a R1200R but it's the same on the R1150R

Ahhh! I stand corrected. I didn't know you could see those little arrows without removing this...



You learn something new every day.