• Welcome to the forum website of the Vincent H.R.D. Owners Club.

    Should you have any questions relating to the Vincent H.R.D. Owners Club, or Vincent H.R.D. motorcycles in general, please contact Graham Smith, Online Forum Webmaster by calling 07977 001 025 or please CLICK HERE.

    You are unrecognised, and therefore, only have VERY restricted access to the many features of this forum website.

    If you have previously registered to use this forum website, you should log in now. CLICK HERE.

    If you have never registered to use this forum website before, please CLICK HERE.

Lapping Head to liner/muff

Martyn Goodwin

Well Known and Active Forum Website User
VOC Member
Will soon have my head back from rebuild with valve seals etc. What is the technique to be used to lap the head to the liner/muff?

Are there any traps for new chums like me to be aware of?

chankly bore

Well Known and Active Forum Website User
Non-VOC Member
Richardson page 44. Avoid side thrust.At least 75% contact on outer surface-more is better, and 100% contact on inner face.Absolutely clean afterwards.Coarse paste outer, fine paste inner. While you've got it apart put a LITTLE bit of gasket sealant on the upper part of the ET55/2's thread into the crankcase if you can partially unscrew them; particularly the timing side rear one. Prove the oil feed to the rear of the piston from the timing cover and check that the oil feed hits the piston below the oil ring at BDC. By the way, valve guides must be reamed with a pilot fitting a modified-i.e. 3/8" nominal i.d. upper valve guide.


Well Known and Active Forum Website User
VOC Member
I always find it easier to hold the cylinder head, combustion chamber facing upwards, in a vice with soft jaws and then rotate the barrel by hand. This ensures that at least one part is held securely and it makes it easier to try to keep even pressure on the joint.
Warning! This thread is more than 11yrs ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.