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I did not do the work. It was 30 years ago (maybe more) and done by Bob Raber's lead mechanic at the time. Might have still been Brook's Cyclery. Anyway, I had it done so I could eventually use the Boyer ignition in the Commando timing cover and get a 2S cam in there. Options were limited back then for electronic ignition, and the 2S cam wasn't a drop in.The cases were modified a little to allow a cam with more lift and modified so that I could use the later style commando timing cover. Different cam bushings may also have been installed. A couple of extra holes were drilled into the timing side crank case for better crank case pressure relief, since the timed breather was not supported with the 2S cam. I don't believe the modification to the oil path at the bottom of the cases was done. Some modifications were done to the timing cover, but I'd have to pull it off to tell you what they were. I'm considering checking and possibly replacing the oil pump, so I will eventually take the timing cover off and revisit this thread with a pic of the inside of the timing cover and timing side case. If I had it to do over again today knowing what I know now, I would not do it the way it was done. I would leave the P11 cam in there and get a TriSpark (or similar) to replace the magneto that was in it at the time. Sure as heck would have been easier. It ran great with that stock cam in there. It's quicker now with the 2S cam and other work I had done at the time, but going fast on the street with P11 brakes is best left behind in my distant no fear years.There are some highly creative Norton tuners here that probably know exactly what needs to be done to get that Commando timing cover on the Atlas cases and prevent catastrophic failure.
I did not do the work. It was 30 years ago (maybe more) and done by Bob Raber's lead mechanic at the time. Might have still been Brook's Cyclery. Anyway, I had it done so I could eventually use the Boyer ignition in the Commando timing cover and get a 2S cam in there. Options were limited back then for electronic ignition, and the 2S cam wasn't a drop in.
The cases were modified a little to allow a cam with more lift and modified so that I could use the later style commando timing cover. Different cam bushings may also have been installed. A couple of extra holes were drilled into the timing side crank case for better crank case pressure relief, since the timed breather was not supported with the 2S cam. I don't believe the modification to the oil path at the bottom of the cases was done. Some modifications were done to the timing cover, but I'd have to pull it off to tell you what they were. I'm considering checking and possibly replacing the oil pump, so I will eventually take the timing cover off and revisit this thread with a pic of the inside of the timing cover and timing side case.
If I had it to do over again today knowing what I know now, I would not do it the way it was done. I would leave the P11 cam in there and get a TriSpark (or similar) to replace the magneto that was in it at the time. Sure as heck would have been easier. It ran great with that stock cam in there. It's quicker now with the 2S cam and other work I had done at the time, but going fast on the street with P11 brakes is best left behind in my distant no fear years.
There are some highly creative Norton tuners here that probably know exactly what needs to be done to get that Commando timing cover on the Atlas cases and prevent catastrophic failure.
