• 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.

Timing cover restrictor discs


Well Known and Active Forum Website User
Non-VOC Member
The timing cover on my twin has no restrictor discs fitted, and the oil feed holes are approximately 50 thou. It has been using a bit of oil, and although the pistons/bores are probably a little past their best, i'm wondering if I should fit discs to the bore feeds and if this is likely to help? If so,what would the recommended hole size be? Any advice welcome, thanks.


Well Known and Active Forum Website User
VOC Member
I would fit the discs. The discs provide a seal for the pathway of the circulating oil. If they are not in place, the oil will have a hard time reaching its destination. In this case, the oil will seep back down into the timing chest rather than oiling the cams. Regarding the cylinder feeds, I have never used them, but I would keep it stock in your case as there is little harm. Do not leave out the seal to restrict flow to the cylinders, instead, use a metal disc with a smaller hole behind the disc seal or close the hole down in the timing cover.

Check your timing cover to see that there is a metering jet under under the decorative cap and the scew. This jet determines the balance of oil delivery between the crank and the cams.

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.