My valves are (really) noisy

[Julio A.]

Hi Guys, I know Airheads are supposed to have relatively noisy valves and for a while, I'm ignoring all that noise coming from my valves.

But recently, I've had the chance of meeting someone who also owns an R65 and we shared a few rides together.  I'm surprised that the other R65 has a really quiet operation motor compared to mine. His valves are are still tappy compared to other motors, but mine is really concerning noisy compared to it.  

My valves' clearances and side to side play are all ok. The timing chain was inspected 6k km's ago and they were far from worn.

Me and some friends were all debating where the noise could be coming from. Some of them told me it may be piston slap, but I replaced my rings for the first time in the bike's life around 8k km's before.

Could it be just because of the 50k mileage difference between the bikes?

[montmil]

Perhaps try using a mechanic's stethoscope to locate the racket.
Is the noise occurring on both cylinders or on only one side?
When did you last remove rockers covers and check valve lash?
There's always the scary thought of valve recession...

Need a bit more info for our on-line diagnostics.

[georgesgiralt]

Hello Julio,
Have you looked at the rockers ? The surface where the valve touch it can worn out. This has the consequence that the valve start to open up, then closes back when the contact is made in the crease. This make a lot of noise.
If you have a fiend good enough to remove one of it's rocker and compare to you noisy one, you should know.
You do not have to buy new one. One can grind them clean, polish them and harden them back. It has been done a couple of time on the 'ol R65 of mine.

[Tony Smith]

You do not have to buy new one. One can grind them clean, polish them and harden them back. It has been done a couple of time on the 'ol R65 of mine.

And I bet they lasted longer after that too, BMW were just a bit stingy with the the depth of the original hardening.

Another often hard to find source of "valve" noise is the whole rocker assembly sliding on the shaft, a question for Julio - did you set this when you put the engine back together or did you not know about it?

There are many roads to a "cure" the simplest of which involves backing off your head tension and using a "C" clamp and a couple of sockets to maintain the rocker shaft clearance whilst you re-tension the heads. Other "solutions" involve shims, torrington bearings and even replacing the rockers with the latest/last model.

Or, if you identify this as the source of your noise, you can also just ignore it.

[Bob_Roller]

What is the rocker arm side play clearance ??

I have mine shimmed to about a .004 in., .1 mm clearance when cold .

One thing I had happen early on with my '81 R65, the needle bearings in the rocker arms, the bearing shell, cracked out and allowed the needles to exit the bearing through the gap in the blocks at each end of the rocker arms .

But, you would notice small metal bits in the rocker cover when you removed it, if this was happening .

Ok, another thought, it makes a difference which way the rocker arm shaft is positioned, there is a drilled passage to allow oil to the bearing on the other side from the oil supply .

If the blocks at each end of the rocker arm and rocker arm shaft aren't put together correctly, no, or minimal oil will get to the bearings in the rocker arms .

Can't remember which of the cylinder hold down studs have the oil supply to the rocker arms .

You stated that you replaced the piston rings, I'm assuming you replaced the head gaskets, did you retorque the nuts again after a few weeks of use

[tunnelrider]

I'm not much help with where the noise comes from Julio, as my R65 (176K km) makes a bit of a racket while running also.  But I have swapped heads with another engine and have to say it hasn't made much difference to the sweet cacophony.  What I do know is that if you notice your valve noise getting noticeably louder or a different pitch then you need to inspect the engine side of the heads, as I had a valve seat come loose after the valve noise changing.  I reckon 50K difference would have a fair bit to do with it.

[Barry]

Perhaps the later rocker set up with shim adjustment is different but I thought the rocker arm side play clearance for earlier types was essentially zero or no more than the oil film. When you attempt to move the rocker arm sideways there should be no perceptible play other than seeing the oil film move.

The BMW workshop manual states "Zero but free moving"

I know mine are set to a lot less than 0.004".  I'd say no more than 0.001" -  0.0015".  

Another contributory factor with valve noise is said to be valve seat contact area. As the valve contact faces wear and become wider they make more noise.

[Einar]

X 2 on the rocker arm side play + seats.

2 additional comments:
- I would also make sure the torque is adequate for all parts of the cylinder including valve cover.
- Are your springs old or brittle?

[Julio A.]

Wow, that is a lot of things to check. haha

I did set my rocker side play clearances using the oil film as the guide. I just checked that again. It's still good.

Valve clearances are still pretty much the same as when I set them 10km's ago.

How can I determine if the rocker part that contacts the valve is worn?

Needle bearings are intact and complete.

I re-torqued the heads when I replaced my head gaskets after 1000km's.

My Springs are the original ones and are definitely old. how do you know if they're already brittle?

My mechanic friends and I inspected my valves around two months ago. They said the valve has wear, but it's still in good usable condition.  

it makes a difference which way the rocker arm shaft is positioned, there is a drilled passage to allow oil to the bearing on the other side from the oil supply .

If the blocks at each end of the rocker arm and rocker arm shaft aren't put together correctly, no, or minimal oil will get to the bearings in the rocker arms .

Ok, I don't remember doing any aligning of a oil passage when I installed the rockers. Does the shaft have a hole of some sort that I align somewhere?

I did test my bike before I started it up before by operating the starter with the plugs out of the engine. I let the engine run until oil dripped out of both rockers. I noticed some rockers wept more oil more so than their counterpart.

Thanks for the help guys.

[Barry]

Ok, I don't remember doing any aligning of a oil passage when I installed the rockers. Does the shaft have a hole of some sort that I align somewhere?

The off centre holes or punch marks shown here in the end of the rocker shafts are the external indicator of correct orientation for the internal oil holes.

[georgesgiralt]

How to check the valves rocker ?
Remove one and look at the point where it contact the valve head.
The rocker should be highly polished metal. Sometimes with blue lines (or zones)  around in the metal (it is the tell tale of the thermal hardening). When you look at the rocker by the side, the contact surface should be a very smooth curve without irregularities or pits. Otherwise, and whatever small are the pits/surface variation, your rocker need to be ground, polished and heat treated.

[Barry]

If you need to grind the rockers do a search on ADVrider.  A poster there called ME109 re-ground his own rockers and did a damn good job of it. There was no need for him to re-harden the tips after grinding and when he checked them after some several thousand miles they were still good.    

[Tony Smith]

How to check the valves rocker ?
Remove one and look at the point where it contact the valve head.
The rocker should be highly polished metal. Sometimes with blue lines (or zones)  around in the metal (it is the tell tale of the thermal hardening). When you look at the rocker by the side, the contact surface should be a very smooth curve without irregularities or pits. Otherwise, and whatever small are the pits/surface variation, your rocker need to be ground, polished and heat treated.

Alternate method - set the gap using your feeler gauge, after removing the gauge, "rock" the rocker - if the movement looks greater than the width of the gauge then your rocker "heel" has a furrow in it and you are going to have to grind them.

[Tony Smith]

If you need to grind the rockers do a search on ADVrider.  A poster there called ME109 re-ground his own rockers and did a damn good job of it. There was no need for him to re-harden the tips after grinding and when he checked them after some several thousand miles they were still good.    

I am happily prepared to bet that situation will not last. The heel of the rocker is hardened and BMW are famous (notorious) for the parsimonious  depth of their hardening. They really do need to be re-hardened.


I first became aware of how stingy BMW are with hardening the first time I looked at a damaged crank with a view to rebuilding. I bought in advance the smallest under-size bearings and sent the crank to a machine shop, they in turn reported that they had ground the crank to size but had completely removed the hardened layer in the process.

The resulting re-think/re-group had the crank welded up using a high-tech rod designed for heavy engine crank salvaging and then ground back to just larger than standard size, hardened and then finish ground.

Sadly that crank broke a short while after I gave the engine back to the owner. Happily the crank breakage had nothing to do with my rebuild, but more to do with the WOT after he ran into the back of a car which proceeded to fairly neatly fold around the motorbike keeping it more or less upright - in the process the bars became bent and throttle cables stretched out. According to onlookers the poor thing howled like a banshee for quite some time before the crank broke - nobody was game to go near it as the car's fuel tank had been ruptured and there was fuel everywhere.

Oh, and the rider was undamaged aside from a bit of shock and some very minor abrasions, he was sitting in the gutter 50 metres away smoking a cigarette and contemplating the fundamental unfairness of life - that was the second time he had pranged that R75 in very similar circumstances - I just reckoned he didn't look where he was going.

[Kookaburra]

  "According to onlookers the poor thing howled like a banshee for quite some time before the crank broke."

The thing I love about you Tony is that you have always got a horrible yarn of experience which makes me feel better about my thankfully relatively uneventful and peaceful two wheel world.

Now are you and the kitchen sink signing up for the 2016 Scrapheap Ride? Youve been an almost gunna for the last 2 years.

Many regards, Chris