1991 R80

[murphcx1]

Hi,

I have a very annoying tapping sound from the left hand (my left when I'm sat on the bike) valve set - having adjusted the valve gaps, I suspect that it verticle play in the rocker body of the outlet valve. Can I adjust this? I have seen people 'clamp' the rocker body on Youtube, but suspect that this adjustment only works on earlier models. I think I need to buy some shims and add this to the verticle rocker body. did I get this correct?

thanks

[Kurt in S.A.]

I also don't think they're adjustable. Have a look here and see the shims that are called out:

https://www.realoem.com/bmw/enUS/showpa ... Id=11_1790

You can read more about the '85-on rockers here:

http://largiader.com/tech/rockers/

Kurt

[Rob Frankham]

The shims supplied for the '85 on' pattern rocker arms can be used with the '76-84' rockers to take up excessive wear. Largitader opines that there is still some movement in the rocker blocks to affect some adjustment but, in my experience, this is so small as to be inconsequential. Whether you decide to use shims or some other form of adjustment, you must ensure that the rocker has free radial movement. Even the slightest restriction may mean that the valve is slow to shut at revs, which could be disasterous.

The other approach is to replace the rockers with the 85 pattern ones. These are actually allowed a small amount of movement by design, the plastic bushing at the top of the rocker will reduce any attendant noise from lateral clearance.

Rob