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[Norm]

Hi Mark, there was no issue before the heads were done up I have watched the rocker movement the Thackery washers all seem to sit properly and as it is kicked over slowly nothing appears to move as the exhaust valves close, you can't feel it with you fingers but I can clearly hear it 50 feet away and my hearing isn't the best. Heads are at the head man and he says he will come up with an answer. Let you know how we get on

[Mark M]

Well that would be a good chance to do those rocker washer jobs then! I found that most of the 4 on my Mk1 could be done simply by fitting an extra solid thrust washer in place of the spring, only one set couldn't and I re-fitted the Thackeray washer. (I didn't have access to a lathe at the time) Guess which is noticeably noisier? Oh well, on the jobs list!
REgards, Mark

[simon]

Probably not the answer but when I rebuilt the Ducati 860 the rockers made a devil of a clack as they came over the cam (it would be cam followers on the Inter) but once the bike was started and the oil pressure was up the whole thing quiet ended down.

[Mikey]

Hi
I had the same problem on a BSA A10 650 cc twin. It took many attempts to isolate the cause despite stripping it many times. The answer was a valve guide that did not move on the bench but with the swipping action of the rocker arm it moved a little then suddenly clicked back into place. On running the engine it sounded like a hammer hitting a metal tray.
Hope this helps.
Mikey

[Norm]

Thanks Mikey, sounds exactly like the problem be the head man yesterday assures me that there is nothing wrong with the head. His work is the best we have here. Only thing I can do is put it back together tomorrow and see what happens. I pray it is ok but I see no reason to be optomistic about it

[Mikey]

Hi Norm,
Before rebuilding, to check guides are tight, put head (the bikes not yours)in over 15 mins on about 180 electric or the gas equivalent. Take out use some thing that will not damage guide (alloy bar?)and tap guide if no movement then its not the guide.
Hope you get it sorted.

Mikey

[Mikey]

sorry for incorrect spelling this is correct ignore earlier post,

Hi Norm, Before rebuilding, to check guides are tight, put head (the bikes not yours)in an oven for 15 mins on about 180 electric or the gas equivalent. Take out then use some thing that will not damage guide (alloy bar?)and tap guide if no movement then its not the guide. Hope you get it sorted. Mikey