good cam profile for a heavy, geared fast MK3?

Any real seat of the pants reason for going to a special $$$ grind? Or should I just use the stock 850 cam for a heavy, high speed geared MK3 ?

To me...
The stock 1S grind is quite good for a commando and MKIII which IMO is a spirited TOURING bike.
But since it is a 828cc and only 10% bigger than a 750, in our group we have used a megacycle 5600NR: http://atlanticgreen.com/images/cam630.gif which is almost identical to a Web 132: http://atlanticgreen.com/images/cam931.gif
Worth the extra $...? Hard to say. But I would not pay for a ricky racer cam. It's easier to just lie about it, for bragging rights, and instead enjoy a mellow well natured cam.

When it comes to changing cams, I have not seen a before and after on this forum. I know what happens when you fit the two race cams into a 650 Bonneville - you get a well-defined strong power band from 4000 to 8000 RPM, instead of one that comes on at about 2000 RPM and peters-out at 7000 RPM. But I don't know what the Norton cams do. I suspect they might be directed at gaining more mid-range grunt. Raising the rev limit seems pointless.

I have a pre MK3 bottom end it might have a good set of followers and a good cam, gotta get the MK3 apart first

jimbo said:

I have a pre MK3 bottom end it might have a good set of followers and a good cam, gotta get the MK3 apart first

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Be sure to keep lifters in correct order with original lobes.

In reality the isolastics make a commando a NOT ideal pack mule. But lightly loaded you won't put the isos bottomed out on the secondary buffers.
I would expect one of my bikes to leave Boston area for the west coast and fully expect to make it...MY body not so much any more. 60-80 on the highway, hot cam not needed.

There is a definite power and torque advantage to be had with a different camshaft. Jim Comstock seems to believe that the combination of a Fullauto Technologies cylinder head and a Webcam 312B cam will provide a boost in power from off idle. I can only agree. With a nice, fat midrange.

I would think that for a road bike you would be looking for more midrange torque. If you want to cruise at 70 you need torque to deal with
the inclines. Sure, you can go down a cog but Id rather have more torque than you need. It makes riding distance so much easier.
That said, is there such a cam? We dont want to lose low end torque really either.

Even with a Commando-based race bike, it is usually more midrange torque you are looking for. The gearbox is a torque multiplier. A close ratio gearbox combined with high overall gearing and the heavy crank gives fastest acceleration. Top speed is largely irrelevant, but depends on how fast you can get around the corners and into the next straight.
Hot cams rely on resonance in the exhaust system to work properly. Any back pressure will usually stifle them to a large extent. With normal mufflers, you will still get more go, but to get the max you usually run into noise problems.
Ashley on this forum uses a 2S Combat cam in his 850 and says it performs well, but there is no way of assessing before and after from what he has said. Most guys when they fit hot cams are changing more than one thing at a time. So the effect of changing the cam on it's own becomes largely unknown.
In my Seeley, I use a normal 850 cam but slightly modified. It performs excellently with the 2 into 1 exhaust system - fast enough to be competitive in historic races. But it is optimised and it is too loud. The 2S Combat cam would be better because the exhaust valve opening point would be later when the cam is advanced to suit the exhaust system. If the exhaust valve opens too early before bottom dead centre, the noise levels can be horrendous, even though you might get better performance.