What Cam?

Is there a seat of the pants way to tell what cam might be installed in a Commando engine? Aside from actually going into the engine? Acceleration characteristics or idle cadence maybe?
Just curious

There was a device produced by the Norton factory which was used by the racing department whenever they lost their notes. It consisted of a stethoscope with a digital readout which plugged into an analogue computer. There was a printout which came off an ASR33 teletype, and defined the camshaft number and the timings. I believe Mick Hemmings has a warehouse full of them in London, and they are going cheap for this week only.

Don't be lazy !

Facinating sonic way to map opening and closing points, are ya pulling our legs acotrel?

MIke i asked this very question about my 1st Combat to several lists to get back the 2S cam wasn't quite as spunky as standard across a parking lot spring but evenly matched though midrange when 2S start to pull ahead til like another piston added mid 6000's and beyond. If really maxing out on 19T Combat mine would stretch wrists and lift front 1st and 2nd as tach swept past 6800. Best way is dial guage and tedium with degree wheel and charting if not sending it to Comstock. On non Combats someone else will have to pipe up to tell w/o measuring.

Would I lie to you ? - Trust me, I'm a doctor !

acotrel said:

Would I lie to you ? - Trust me, I'm a doctor !

Click to expand...

OK-I believe you, but does it matter what phase of the moon or ocean tides are when I use this? Will being in North America make it too far from GMT for the timing function to work? :lol:
Yes I am being lazy, but I'm also curious.

MikeG said:

acotrel said:

Would I lie to you ? - Trust me, I'm a doctor !

Click to expand...

OK-I believe you, but does it matter what phase of the moon or ocean tides are when I use this? Will being in North America make it too far from GMT for the timing function to work? :lol:
Yes I am being lazy, but I'm also curious.

Click to expand...

I don't think there is any easier way t o tell except what Hobot has said to you. I've had twin cylinder British bike will all sorts of cams in them and I could only pick the difference because the race cams had a strong 'cam spot'. But if you are comparing various types of road camshafts, they all feel much the same in certain parts of the rev range. Different exhaust systems change that anyway.

Well you can remove the rocker covers and measure valve travel for each valve with a cheap Harbor Freight dial gauge. Divide the travel by 1.13 and you will have cam lift. Then look it up in either a shop manual or on Dyno Dave's site (atlantic green).


Russ