Valve noise??

[79beem]

Maybe i should have asked,
How do poorly adjusted valves sound ?
How does it differ from the tap,tap,tap that i have now ??  

[Rob Valdez 79 R65]

You actually have a lot of lee-way between too tight and too loose.
Too loose and you will lose power.
Too tight and you might burn a valve.
There is a poster on the Boxerworks forum that says he keeps his at zero clearance - but he checks them often...

Have you checked your clearances YET???

[79beem]

No not yet,

 I'am new to R65's and wanted to pick your collective minds b4 i started pulling her apart.

i'am going to on the wkend.

[Rob Valdez 79 R65]

When you adjust your valves, you need to rotate the engine.
Some folks put their transmission into 2nd or 3rd gear and turn the rear wheel.
I prefer to remove the front cover, and turn it with my 3/8" ratchet w/allen driver inserted into the alternator bolt.  If you do it this way, remember to disconnect any and all ground wires from the battery before removing the cover (you can short out on the diode board, and possibly damage some diodes).
You also want to turn the engine in the direction of normal rotation, i.e. clockwise when looking at the engine from the front.
When working on one side, you want that piston at top dead center on the compression stroke.  This will have both the intake & the exhaust valves in the "relaxed" position.

[montmil]

+ [smiley=thumbup.gif] on Rob's valve lash procedure. I also pull the sparkle plugs as it's much easier to rotate the engine while adjusting and re-checking your work.

Monte

[Tony_T]

My '79 R65 has just started to develop a metallic tap as well.
Most noticable at idle, between 3000 and 3500rpm and is definitely worse under load.
I've checked valve clearances and rocker free play. All good.
Plus it is the speed of just one valve, so I suspect maybe a lifter or camshaft.
Sounds like I'll have to pull the pots off over the weekend and have a look.
Bugger! I wanted to go riding...........  :-/

[Rob Valdez 79 R65]

It's always a good idea to look at the lifters at least once in your ownership.
I've seen pictures like this a couple of time.  But never from a R65, that I can recall.
This one is from a R100.

[Tony_T]

I figured, it's not a big job, so I just went out and popped both pots off and had a look.
The lifters and cam both look nice. No pitting at all.
Now I'm wondering........  :-/
Anyone got any other suggestions before I start pulling things further down?
It's a very distinct metallic 'tap' at the same speed you would get a noisy valve.
Any words of wisdom gratefully received.  

[Rob Valdez 79 R65]

Your [exhaust] valves are not closing up on you between checks?
You are measuring the gap before adjusting them, and writing this info down with date & mileage, so you can see if there are any changes going on?

[bruce_launceston]

The're not called 'tappets' for nothing ........

Other noise source could be timing chain due for replacement?

[Tony_T]

The're not called 'tappets' for nothing ........

Other noise source could be timing chain due for replacement?

  Yeah, but this is one single metallic tap and is definitely not normal.
I'll give it a really good look over and measure everything over the weekend and see what I come up with.

[Barry]

Most noticable at idle, between 3000 and 3500rpm and is definitely worse under load.

Hard to see how valve noise would get worse under load as the valve train is only subject to the load of the valve springs and while cyclic should not change due to normal engine loading. Does that make sense or am I missing something ? I'd like to think for Tony's sake there was an alternative source of noise as a result of engine loading other than the big ends. On the other hand Tony is saying "at the same speed as valve noise" which means half engine speed and that would not sound like big ends.

While you have access to the con rods can you feel any play in the big ends?

[Rob Valdez 79 R65]

Most noticable at idle, between 3000 and 3500rpm and is definitely worse under load.

And it may be "detonation", "pre-ignition" or whatever term you choose for when the mixture is igniting before it should (by spark).

Try some fresh gasoline, perhaps a higher grade, and check the timing.

[Tony_T]

Thanks for all the input, gentlemen.
Had a chat to BMw mechanic yesterday and he's uggested that a valve may be sticking. i.e. not returning to the closed position quickly enough.
Sounds reasonable as it does sound like a very load valve noise.
Anyway, I'll strip the whole thing. They're dead easy to work on, so I may as well give it a good once over and hope I don't miss anything!  

[Bob_Roller]

A real remote possibility of the origin of the noise, I had a rocker arm needle bearing come apart .

The sheet metal flange of the bearing cracked out and allowed a few of the needles to escape through the gap in the support blocks that are at each end of the rocker arm .

All of the metal pieces ended up in the oil sump .