valve rattle

[scribbles]

I cant seem to get rid of my valve rattle no matter how carefully i set up the clearance and end float. the valves are all new, its nice and smooth when cold and then starts clicking away like mad. i have been told it's probably because the cam shaft is worn.
does anyone have experience of this and is it possible to replace the camshaft with the engine in the frame? looks doable from the drawings but clymer tells me i have to get at it from the flywheel end too.
shame to hear this after pulling the bike apart and having the engine in bits on my bench.

 

[pooh]

They all do that Sir Have you set the rocker clearences....from mount to mount

And you could probably change the cam shaft with the engine in....but why bother by the time you have removed all you need to you could drop the engine just by removing the engine mounting bolts.....

 

[Rob Farmer]

Clymer probably say you need to get at the flywheel end because the oil pump inner needs to align with it's drive on the end of the camshaft. I took the cam out of my 100PD with the engine in the frame without any problems at all. You will need to slacken the camshaft retaining bolts off though to allow the cam followers to be pushed up out of the way. If you align the valve timing marks before taking the cam out it will make things alot easier.

Before refitting the cam check the endfloat of the front bearing to the camchain sprocket.

Are you running 20/50 Oil?

 

[Steptoe]

Before you start to pull the engine apart, check the cam followers for cracks.

 

[scribbles]

Clymer probably say you need to get at the flywheel end because the oil pump inner needs to align with it's drive on the end of the camshaft. I took the cam out of my 100PD with the engine in the frame without any problems at all. You will need to slacken the camshaft retaining bolts off though to allow the cam followers to be pushed up out of the way. If you align the valve timing marks before taking the cam out it will make things alot easier.

Before refitting the cam check the endfloat of the front bearing to the camchain sprocket.

Are you running 20/50 Oil?

i have just put 10/40 oil in because it was all i could get and i'd got water in the oil whilst offroading but had 20/50 before and it wasn't any quieter.
did changing your camshaft stop any valve noises? i know that all pushrod and rocker type engines make noise but my friend has the same rocker end float and valve clearance setup on his r100gs and you cant hear any tappet noise at all even when its hot. if putting a new camshaft in gets rid of my valve rattle i'd be a happy man.

 

[scribbles]

Before you start to pull the engine apart, check the cam followers for cracks.

would this make alot of noise too?

 

[(RIP) Bin Ridin]

My R100GSPD make a hell of a clanking from the top.
Set valves etc etc, still the same.
I read somewhere that if the valve seats are cut to same angle as the valves, you get a noise and it does seem to be that kind of pok-pok noise such as you get when you drop a valve on its seat while grinding.
YMMV.
Bin

 

[scribbles]

the noise isn't the sound of the valves themselves but more the clicking tappet noise of the pushrods and rockers. the man who told me its probably a worn cam said to set my valve clearance at TDC. then turn the engine over a bit past TDC and if the valve clearance gap gets bigger then the cam is worn. i've checked this and it went from .1 to .15mm which makes sense that it would make it click like mad. can anyone give me advice before i go off on a wild goose chase?

 

[mikyh]

The rockers

many years ago I rebuilt a R750\6 with a friend. it clicked madly from the heads, no adjustment helped.
It was in Rome, Italy, and we befriended the owner and chief mecanic of the local BMW motorcycle garage. They suggested that because the rockers are old, they might have their pushing surfaces deteriorated so when adjusting all seems well, but actualy the gap is much bigger.
we were young and "poor", so we took the rocker out and "regrounded the pushing surfaces.
It worked for 10 minutes, than it became louder still.
We neglected to undrstand the those surfaces are surface treated to withstand the beating they get.

so, my suggestion - check the rockers. it's also easy to begin with
Miky

 

[DrFarkoff]

as a matter of interest did you check the rocker shafts for ovality? I mean thousands and thousand of miles with predominant wear on one face??

I did an experimant I had an R80ST that always rattled so I took off the rocker arms removed the needle rollers cleaned everything well with parafin and rebuilt the rollers using graphite grease and then rebuilt everything back up as was with lashings of grease and it quietened things substantially for about 3000 miles

The real cure? new rocker shafts(if the originals turn out to be oval) and new roller bearings in the rocker arms

 

[(RIP) Bin Ridin]

Maybe try setting the clearance by tightening the screw to a touch, then backing off the angle corresponding to the clearance. I think I used that on a Triumph where the screw pitch was 40 thou, so a quarter turn was 10. No feelers needed. Am I hallucinating?
Bin