David,
I have a question. Why do stock followers not work and what does?
I have a question. Why do stock followers not work and what does?
Vernier Cam
- Thread starter davidd
- Start date
Followers
Rip,
I believe that the only way a symetric cam lobe will work in a Vincent is with a roller follower. This is because the standard follower makes contact with the cam over such a wide area that the geometry going up is different than the geometry going down, which I know that you know. The photo of the follower on the left shows the hybrid roller follwer, which allows the use of such lobes. There is a huge amount of research on roller lobes and there is very little on asymmetric lobes.
David
Rip,
I believe that the only way a symetric cam lobe will work in a Vincent is with a roller follower. This is because the standard follower makes contact with the cam over such a wide area that the geometry going up is different than the geometry going down, which I know that you know. The photo of the follower on the left shows the hybrid roller follwer, which allows the use of such lobes. There is a huge amount of research on roller lobes and there is very little on asymmetric lobes.
David
Gotcha..... again: great work!
Now Trevor....
Screws don't just don't fall out unless you want them too.
Screws don't just don't fall out unless you want them too.
I have real reservations about the use of roller followers. Several years ago I bothered to calcuate where the cam face to follower face is all round a lift curve. It is a nightmare of changing position and direction and I doubt the capability of a roller to change direction rapidly enough. Curved based solid followers are a different matter. And yes, I do know that the Irvin Vincents use rollers and those chaps really seem to know what they are doing.
Harleys have used roller followers since the year dot, since 1938 they incorporated hydrualics into them as well ,they really are fit + forget. Most american cars are similarly equipped. Even Rolls-Royce use them in their v 8 engined cars. They do not wear and are kind to the camshaft lobes too. Roller tipped rockers are a good one also, but it is near-on impossible on a vin. I will now sit back and wait to hear from some smart alec who tells me "john doe did it years ago".
Thanks, David, I figured there was something "a bit special" just from looking.
Just to complete the thread, below is a photo of the Terry Prince MK4 cam, which is the race cam. The followers are Terry's also, but they are only used with the MK5 cam which has lobes designed for the followers. The MK4 race cam uses standard followers.
David
David