Cam Chain Tensioner Puzzlement

[bc1100s]

I was doing the chain tensioner update on a friend's 1150GS and what came out has me puzzled. No spring (!) and what seems to be an extra part. Could this have been an in-production update / stop-gap measure to try to fix the issue before an ultimate solution was found? Everything went back together with the new parts no problem. So, who here can clarify this for me?

 

[ragtoplvr]

I was doing the chain tensioner update on a friends 1150GS and what came out has me puzzled. No spring but what seems to be an extra part. Could this have been an in-production update / stop-gap measure to try to fix the issue before a final solution was arrived at? Everything went back together with the new parts no problem. So, who here can clarify this for me?

As I recall I was sold one of those also and it did not work, I think it is a early attempt to fix it. the diameter is different so it is not mixed parts. I could be wrong, it was several years ago.

Rod

 

[bc1100s]

Thanks for confirming, Rod.

 

[gsaddict]

Old style has a 17mm hex
New style has a lower profile 15mm hex

 

[bc1100s]

Old style has a 17mm hex
New style has a lower profile 15mm hex

Your image illustrates what came out of my 1100S and what I've seen removed from outer oilheads. And what replaced it.

My original image shows what just came out of an 1150GS. It has a 17mm hex sleeve, a piston, an additional part I'd never seen before...and no spring.

It was successfully replaced with the updated parts.

 

[PGlaves]

Your image illustrates what came out of my 1100S and what I've seen removed from outer oilheads. And what replaced it.

My original image shows what just came out of an 1150GS. It has a 17mm hex sleeve, a piston, an additional part I'd never seen before...and no spring.

It was successfully replaced with the updated parts.

It looks to me like the original photo shows the parts from an F650 or F800 stuffed into the outer shell from the original R1100 tensioner. Notice that when in place the actual tensioner would be in a position not to drain down. It might have been BMW's first attempt, or somebody's shrewd retrofit.