What? This post has been dormant for 3 years!!!?!
Here I come...i recently had my first track experience on my Norton racer, and although I am obviously a pretty bad rider, the bike seemed pretty fast...
So, the bike is a Slimline Featherbed, with a Dunstall longer box section swingarm, Commando fork, full Dunstall fairing, 18" alloy rims and road Avon tires (yes, it is my road bike as well)...Fournales air/hydraulic shock absorbers. The bike is probably significantly lighter than a Commando and is definitely lower. i weigh 72kgs and I am slim.
Engine is 850 Commando, with PW3 camshaft, lightened crankshaft balanced for the frame (don't know the exact factor, but it works), much lightened rockers (Dunstall most likely), black Diamond valves with race springs, polished rods, flowed 32mm head, rubber mounted twin Amals MK I 32mm with splayed manifolds 260 main jets and velocity stacks, Pazon ignition, Dunstall exhausts. Stock primary transmission, 22/42 secondary. 20% Avgas.
https://farm9.staticflickr.com/8839/179 ... 5e_o_d.jpg
So, in Dijon, the circuit has a pretty long straight (close to a mile I think) that starts as a steep climb, keeps going slowly uphill for most of its length before going flat for the last 1/8mile. Tucked in the fairing, I spotted my magnetic Rev counter flirting with 7500-7800RRPM and my odometer wobbling around 130Mph.
A friend of mine, riding a Vincent Black Lightning that was previously clocked there at 131Mph told me he could just about follow me but not pass me. I couldn't quite believe that I was going at that speed, so I posted on a French forum specialized in vintage british bikes and a hot discussion ensued, several members calling me a liar or a dreamer, while others (including some who had seen the bike on the track) mostly took my defense and declared that the bike was indeed very fast.
On the last lap of the last session, I experienced some valve float at the end of the straight and immediately lost power. It seems the valves didn't touch the pistons (we opened the engine and couldn't see anything on the pistons) but both exhaust valves were slightly bent without any other problem whatsoever anywhere else in the engine.
A calculation based on the Norton data shows that if indeed I was revving at 7500 Rpm with a 22T my speed was about 130Mph at that point.
Do the eminent members of this forum feel it is plausible or simply a vast exageration from my Smiths magnetic instruments?