G
Graham Smith
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Have now created a poll at the top of this thread so you can express an interest in one of Norman's Modified Valve Lifters.
ET: Engine (Twin) Modifying the Valve Lifter Mechanism on 1,000 cc Engines
- Thread starter timetraveller
- Start date
Great idea.
I think it comes with assembly instructions I may have a copy somewhere
If you can find them it would be very useful to see what is involved. From the photograph it looks very compact and my idea might be redundant.
Both VOCS & Maughans already provide a modified valve lifter seal system that uses a seal from a valve guide and I believe its similar to the Ron Kemp one. Its fit and forget and certainly seals OK and I have not have to change the actual seal in 15 plus years and also fitted it to several bikes. Note it cannot be used on a Comet.
Firstly, thank you to those who put the details of the SC seal on here. I had missed out on that. The following things come to mind when comparing their system with mine. Neither will work with the singles, only the twins. Both require removing the timing gear to fit and, if a leak ever develops, it seems that would also have to be done to replace the sealing system. They differ in that my system attempts to stop oil ever getting into the ET169 whereas the SC one tries to stop it getting out. As for longevity then I would have thought that a valve stem seal should have a long life when used in this application but my use of the ET183 timing cover seals should also give a long life. How often does one feel the need to change those seals when working on the bike?
At the time of writing this five people have expressed an interest and I will wait a few days before trying to get a quotation for the machining but this note is just to let those with a potential interest know that there is still some possibility of it going ahead,
At the time of writing this five people have expressed an interest and I will wait a few days before trying to get a quotation for the machining but this note is just to let those with a potential interest know that there is still some possibility of it going ahead,
I can add that I have had the SC version on my bike for a couple of years now. It does reduce the oil loss to a small degree. It's definitely not sufficient.
My bike doesn't leak there and it just uses the original sealing washer to keep the oil in. The reason it works though is because I have put a stronger spring inside the timing case that pulls back directly on the lever instead of just a weak spring pulling the levers together. With the washer squeezed firmly by this stronger spring it seals well. This was from a suggestion from Neville Higgins in MPH. This is the way he seals his also. John McDougal had given me a couple of lip seals to install in that mechanism, but when I was putting my bike together I couldn't find them.
25 years ago Frank Griffin gave me the tip to make a hinge in the ET166. The ET166 bends every time you use the valve lever, this hinge is easy to make from two pieces of round or hexagonal steel, 8 mm round (or 8 mm hexagonal) and both 1" long. Drill a M3 hole on one side, 10 mm deep, in each piece, connect the two pieces by filing a fork, connect the two halves of the fork with a 3 mm round pin, clinch both sides of the pin. Saw the ET166 exactly in the middle, cut thread M3 on both sides (10 mm long) and make sure that the ET166 with hinge is exactly as long as it was before sawing it through. In those 25 years I have had a lot of problems with everything but the modified ET166 never gave a problem, and not a drop of leakage
