rocker arm shafts worn?

[Sempione]

Hi,

I noticed that the valve clearances on my R1150GS (year 2000 with 120k km on the clock) change quite a lot depending on the position of the rocker arms (vertically up or down) on inlet and exhaust valves and on both cylinders.
The rocker endfloats are ok.
Could this be caused by worn rocker arm shafts?

The LHS cylinder also recently developed an annoyingly loud ticking.
It is not coming from the throttle body. The left hand tensioner was already replaced with the new model. My guess is that it is valve train related (slow frequency).
So while at it I also want to check the cam followers, pushrods and the cam and if necessary replace them.
I'm playing with the thought to replace the entire LHS rocker assembly with a good used one.

Am I right if I assume that the cylinder head needs to be removed to replace the rocker assembly and for access to the cam?
Just want to have new gaskets ready if necessary.

Cheers,
Niki

 

[MattW]

Hi,

Am I right if I assume that the cylinder head needs to be removed to replace the rocker assembly and for access to the cam?
Just want to have new gaskets ready if necessary.

Cheers,
Niki

You don't actually need to remove the cylinder head to remove the cam carrier but as you have to remove most of the cylinder head stud nuts, thus de-tensioning the head gasket, I'd remove the head and change the head gasket too. Others may recommend differently

 

[Steptoe]

I'll post some pictures of a bike that i'm working on at the moment. Might interest you.

 

[dancata]

I'll post some pictures of a bike that i'm working on at the moment. Might interest you.

 

[Stewart H]

I'll post some pictures of a bike that i'm working on at the moment. Might interest you.

Interested to see what you have found

Stewart

 

[Steptoe]

Knocking noise from the R/H side - R1100 50K miles.

Cause = Worn cams, cam followers, cam/rocker holder and rocker arms.

The cylinder head after all the rocker gear and camshaft has been removed



Cam/rocker holder.


Cam and cam followers.


Camshaft.





Cam followers in the holder.



Cam followers


New cams and followers

 

[sproggy]

Any indication as to what might have caused that damage after such a low mileage? Oil starvation? Wrong clearances?

 

[MattW]

Bloody 'ell - those cams / followers look like my old Mk2 Cavaliers (renowned for eating cams due to bad design / oil starvation).
Although in your case the followers look pretty well hammered - bad clearances for a long time?

 

[Steptoe]

Any indication as to what might have caused that damage after such a low mileage? Oil starvation? Wrong clearances?

Haven't a clue - The bike was taken apart in a BMW main dealer, and after a quote of £2k to put right was quickly rescued and dropped off with me .

Never sure what your going to find when it's been taken apart by someone else and all the parts chucked into a bag and the rest of the bike left as it was and given to you to get on with. .
You just have to make sure there are no hidden surprises in the crank, cam, timing, and you wonder if anyone has turned the engine over with half of it dismantled I'm sure those nice dealer people who've just lost a big would never do such a thing ...... Especially after charging a big wedge of money just to remove the rocker gear.

Anyway, job done and the only noise is the nice rustling of valves opening and closing.

 

[Stewart H]

Theres a lot of brown discolouration in those pics, far more than in my 107000 miler, my money is on oil someone probably put the wrong grade of 20/50 in it
Or left it in too long
Or not enough of it
or bloody hot for a long time

Stewart

 

[Steptoe]

or bloody hot for a long time

Stewart

That would be my guess. But thats all it would be, a guess.

 

[Steptoe]

Looking at the cam followers from the side where you can see them without any dismantling they look fine - But you can see the scoring on the rocker arm spindle seat.

 

[Bronco Billy]

Thats been run with little or no oil that has!

 

[Sempione]

Thanks for the pictures.

I hope that I won't find the cam, cam followers, etc. in the same condition.

Neil, what is your opinion on the head gasket question? Should it be changed if it was de-tensioned for rocker assembly removal?

Cheers,
Niki

 

[Steptoe]

Neil, what is your opinion on the head gasket question? Should it be changed if it was de-tensioned for rocker assembly removal?

Cheers,
Niki

Depends on the condition of the exhaust studs

So long as you don't turn the engine over while the head nuts are off you should be ok - There is still the 10mm allan bolt and few smaller bolts holding the head in place, and if there hasn't been a leak from the gasket you usually have to use force to break the bond and pop the head away from the barrel anyway.

 

[Mzokk]

Thats been run with little or no oil that has!

Think I'd go with that too.

 

[Stewart H]

The strange thing is that the camshaft plain bearing surfaces and those in the head look fine, its as if the lubrication has only broken down on the cam lobes and followers it could even be a hardening issue, it reminds me of old Ford pinto or Vauxhall OHC motors from the late seventies.

Stewart

 

[Bronco Billy]

The strange thing is that the camshaft plain bearing surfaces and those in the head look fine, its as if the lubrication has only broken down on the cam lobes and followers it could even be a hardening issue, it reminds me of old Ford pinto or Vauxhall OHC motors from the late seventies.

Stewart

Bullshit ............

Have a look again at the picture showing the journal where the shaft sits! If you cant see those two score lines then your eyesight is such that you shouldnt be riding a bike!

 

[Stewart H]

Bullshit ............

Have a look again at the picture showing the journal where the shaft sits! If you cant see those two score lines then your eyesight is such that you shouldnt be riding a bike!

No dont sugar coat it, tell me what you think
I did look again

Stewart

 

[MattW]

No dont sugar coat it, tell me what you think
I did look again

Stewart

A career in the diplomatic corps beckons for Bronco Billy