That is all interesting information. I have the Robinson 105s in my bike right now. I was lucky he made me a set since he had said he would stop. I have never had the bike on a dyno to measure it's power. The seat of the pants impression is pretty good. The bike will hit the rev limiter at 6500 RPM in first and second gear. (I try not to do that) I set the cam timing a little bit retarded because I wanted the bike to rev more. I think it ended up with the equal lift 2 degrees after TDC. I decided to try it. It was an experiment that I think worked, so I left it that way. I don't think the bike was quite as eager to hit the rev limiter with the TP cams, but I had them timed at the 4 degrees before TDC as many people advised. The sheet that came with the cam advised equal lift at TDC. I had the TP cams in my bike but I had some wear problems. The problem was probably caused by to much pressure from the TP valve spring kit. I have reduced that pressure now, and with the stelite Garry Robinson cams I have not seen any wear yet. What is the actual LSA angle on the MKII cams? I have heard it is 97? Is that what you have in your Comet now? I think most people around here (British Columbia) prefer the MKII cams from Garry Robinson.
Terrys cams are great if you are using one of his heads. With a standard head the lift with Terrys cams is so great that you run into a myriad of clearance issues, both in the head and in the timing case around the cam follower/valve lifter areas. For me it was an expensive lesson
Martyn, which MK of Terry's cams were you using?
Glen
Glen
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Nigel,
The LSA on the Megacycle Mk2 is 97 at 0.050". Both lobes are exactly at 97.
On a Factory, Mk2 is Intake at 116.25, Ex at 96.5 for an LSA of 106.38 at 0.050".
There were lots of different Mk2 cams from the Factory.
I believe that the low power on the dyno was a result of having no restriction on the pipe. It is not a race cam.
I have been running a cam that Megacycle makes for me. Greg Brillus is running it in his race bike.
David
The LSA on the Megacycle Mk2 is 97 at 0.050". Both lobes are exactly at 97.
On a Factory, Mk2 is Intake at 116.25, Ex at 96.5 for an LSA of 106.38 at 0.050".
There were lots of different Mk2 cams from the Factory.
I believe that the low power on the dyno was a result of having no restriction on the pipe. It is not a race cam.
I have been running a cam that Megacycle makes for me. Greg Brillus is running it in his race bike.
David
A PM is on its way
I did exactly what Gary told me, and set each cam at maximum lift on inlet at 105 degrees ATDC. I then checked the timing, I obtained inlet opens 44 BTDC closes 79 ABDC exhaust opens 79 BBDC closes 44 ATDC.
Pretty symmetrical, the bike runs great !!
Pretty symmetrical, the bike runs great !!
At what lift?
It is marked as a Mk2.
Did you happen to note the equal opening point?
With the timings he obtained the equal opening point would be TDC. I think with these cams that is the ideal timing. Some people say 4 degrees ahead of that, but mine have the equal opening point about two degrees after TDC and my engine seems to rev our nicely. With Vincents there isn't really a problem with low end torque. These are kind of torque cams anyway. John McDougall called the 105s the RV cam. What you want is more revs, because you are always going to have enough low end torque anyway.