Please believe that I don't want to offend you when I say the following, it is well intended. Historic racing started in Australia in 1973 with the declared intent 'to preserve the old racing bikes'. It never did that, the classes have always been used for development. These days it is impossible to find an unmodified Manx Norton here . The 'improvements' have been replica frames with 26 degree head angles, 18 inch wheels, molnar motors, 6 speed TTI gearboxes, and vast overboring. A friend of mine got the shits when I criticised his Manx on a forum because he had over bored it t o nearly 700cc to compete in the Unlimited Period 3 (up to 1962) class. He said 'it is my manx, and I will do what I like with it', recently he converted it back to 499cc, but it's still got 18 inch wheels, so it probably handles like a piece of shit. When the guys buy replica featherbed frames they usually specify 26 degree head angles to make the bike handle like a Suzuki two stroke. To my mind, the reason you ride a manx is to enjoy the experience, if I want t o ride a Suzuki, I won't try to turn a manx into one. The genuine items were developed over decades , and they are what they are. You can buy yourself a Molnar manx and delude yourself that you could have beaten Artie Bell and Geoff Duke in the fifties, but you would not be having anything like the same experience.
Years ago my friend had a long stroke manx on the street, it was painted a beautiful dark red with all the manx lining - in those days we thought 650 Triumphs and Tritons were beautiful, but we were just bloody ignorant. That old longstroker is now being carefully restored back to original and you cannot buy it. As I said and meant it, if someone has an original manx, and particularly a works one, I would pay to ride it just for the experience . The bikes were developed over decades and the 61 model 500 that I once rode was perfection. It was never going to beat an R6 Yamaha, but the experience was everything, and I treasure the memory of it. So what I am saying is please don't paint a moustache on the Mona Lisa so it will brighten up your little life. Think about the young guys who will be following you after you are dead, who will never appreciate what Artie Bell and Geoff Duke did back then. Perhaps you should buy a Type 35C Bugatti replica from Brazil and put lights on it ? I could see sense in that.
Somewhere on Youtube there is a video of the 1950 Senior IOM TT in which Geoff Duke started 20 seconds behind Artie Bell, the previous year's winner, and made up the time and passed Bell just before the flag on the last lap. This clip shows part of that. I don't want to send you on a guilt trip, but you are playing with an important part of our racing heritage :
http://www.youtube.com/watch?v=HHzWScP2T1c