valve question

[chris_blake]

just read the suecanada piece now i am worried i always thought my 86 mono was a bit tappety but assumed they all were. i recently got chatting to a guy on a r100 and this bike had done 180 thousand miles and it was much quieter than mine which has only done 25 thou unfortunately i was on my tdm at the time so could not get his opinion i  torqued and reset them very carefuly but they are just the same there is no problems with performance of the bike and every thing in the head looks fine . i took the bike to a mecanic who said they were very loud but could find nothing wrong  .this mecanic is only used to working on modern machines am i being a bit paranoid or is there other things i should check cheers chris

[Bob_Roller]

If the valve clearances are in spec, check the end-play gap between the rocker arms and the  blocks they rest between, when there is no tension on the rocker arm.

All of mine had fairly large gaps , .010-.012 in., so I got the shims that are used on the upgraded replacement rocker arms, shimmed them to about .002 in. gap, and they quieted down a noticeable amount.

Just saw your in the UK, sorry no metric equivalents for the gap measurements !!!

[Ed Miller]

Does anybody remember what year BMW fixed the valve seat material/valve material incompatibility?  I think Chris's '86 should be all right as far as that issue goes.  I don't know what caused Sue's retainer notch wear; I've never seen that before.  

Sue, were your tappets noisy?  

[Justin B.]

The best I can remember from all of the discussions from here and there it was US model year 1985 which I guess would make all monoshock bikes OK.

Chris, you said you "took the bike to a mecanic who said they were very loud".  If this "mechanic" worked primarily, or exclusively, on jap bikes then the valve would seem EXTREMELY loud to him.  I wore out a couple of valve adjusters on my first /5 because I was used to the quiet valve train on jap bikes.  The dealer came flat out and told me I was over-maintaining the bike and to set the valves and ignore them for 4500 miles.  Of course, this was in the leaded gas days before valve issues cropped up.

The old Beemer rider saying goes, "Noisey valves are happy valves", or something like that.  When you want to start worrying is when they get quiet.  See some of the pics recently posted by Sue...  But, check the end-play as Bob suggested as it CAN add a lot of noise even though it doesn't really hurt anything.

[chris_blake]

thanks guys i will check the end play i proberly am being a bit over cautious , my old bonnie made a terrible racket and i never worried must be an age thing cheers chris

[suecanada]

To my ears and those I asked to listen LRB sounded just fine. It certainly sounded the same since I owned it.

[trolle]

The valve problems came with the changes in model year 1981, for which  the production started in april 1980. All models from the model year 1985 and forward are without the problem.

greetings from a sunny, so and so, north with good driving conditions

trolle

[Yikes]

If noisey valves are happy valves, then mine are in a near constant state of extasy.  Ever since I got the bike (in October) it makes a lot of top-end racket when it runs.  I've torqued the rocker and cylinder head nuts, adjusted the valve and fed it some STP and got some improvement.
My neighbor (a etired machinist and excellent mechanic, but not a BMW specialist) and I ran the bike for a bit without the valve covers to see what we could find, and we were able to change but not eliminate the niose by pushing on the left exhaust rocker with a wooden dowel.
One thing that concerned me, but not my neighbor was that there is some end play in some but not all of the push rods.  I don't know if this is normal, but it seems not quite right to me.  Next time I'm into the heads, I'll pull the rocker arms and see if there is play in the rocker arms that warrant shimming.  Glad to have something else to investigate.   Now if the weather would just warm up...

[Bob_Roller]

Another remote possibility, could be the needle bearings in the rocker arms, have issues.

I found 'parts' in my rocker-arm cover, that turned out to be parts of the needle bearings, the metal shell cracked out, and allowed the individual needles to 'migrate' out in the gap in the support blocks that are just to each side of the rocker arm.

Mine failed before I had 10,000 miles on the bike !!

[Semper Gumby]

Hi Chris,

+1 on the rocker endplay.  I used a really large set of plyers and squeezed 'em together.

The key to valve health is knowing what they are doing.  This means you need to first before doing anything else to them, measure and record the valve clearences before you torque the heads and adjust the valves.  That way you can see what is going on with your valves between service intervals.  If the exhaust valves are tighning up then you have valve recession.  This will eventually require a top end rebuild.  I believe you valves are not suseptible to this so the above procedure is for peace of mind only.

[Danie]

I got a bit of a shock during the past weekend, as far as "noisy valves" are concerned.

 My r65's heads have been rebuilt quite recently, and I also experienced "noisy valves" - before, and even after the heads have been rebuilt. The chap who worked on my bike before, assured me that  the "valve noise" was normal.

Fact is, the noise just became worse, and during this past weekend I decided to remove the cylinder heads myself,  to try and find the cause of the noise.

I think I have found the cause of the "noisy valve" problem on my bike.  Having removed the cylinder head as well as the piston barrel and lifters on the left, I discovered that the front lifter is badly worned - and although the camshaft has not been removed yet, I could clearly see that the front lube on the camshaft is badly worned as well.

I still have to remove and strip the engine , because the I have no  option, other than to replace the camshaft - and at least one lifter.

I will forward a pic of the damaged lifter, as soon as my wife is back from work - she took the camera to work today.

[Justin B.]

Lifter look something like this?  I had to replace 2 of them on my '81 R100 but I caught them in time to save the cam.  This seems to be somewhat common from some of the discussions I've followed in the past, maybe a heat-treat issue?

[Danie]

The lifter from my bike looks far worse than yours.

My wife will be back much later with the camera, but I will send a pic as soon as possible.

The lifter on your pic seem to have a slot on the one side - is this lifter from a R65 or R100?

[Danie]

Hereby attached, is a pic of the damaged lifter.  It has been cleaned with a wirebrush - but it was almost completely black (probably due to heat / burnt oil ) when it has been removed.

Perhaps overheating - during slow riding conditions (in traffic) took its toll.........

[Bob_Roller]

Picture is a bit 'fuzzy', but it's quite obvious that the lifter is not in good 'health' !