I am an idiot. When I bought the 6 speed TTI gearbox, it was because of the very high Manx Norton first gear in the close ratio cluster. I was always getting slow starts. In my shed there are about 3 other gear clusters from various Nortons, and the first gear from anyone of them could be used with the Manx Norton cluster. John Maher raced a Manx, and when he visited me I told him about this problem - he said he has 3 first gears for his Manx, and changes them to suit different circuits. I have only raced the Seeley 850 on smaller circuits. At Winton and Mount Gambier, once the bike is moving, I never go back to first gear anyway. The larger gap between a Commando first gear and the Manx second gear would not even be noticed - just rev it higher in first gear. The slowest corner on Winton is a tight hairpin - I go around it in second gear at about 50MPH with the rear wheel losing traction -it is a bit bumpy.