The new 932s I installed have the stepped spray tubes. They breath through a K&N unibody filter and the engine pushes the exhaust out through straight through peashooters, the valves are stock diameters, but the head was ported by Leo Geoff and the compression ratio was raised to somewhere in the high 9s:1. The engine is fitted with a degreed Web 12a cam (lobe centers are within 2 degrees of spec). I have a 21 tooth countershaft sprocket. In regards to the cam my thinking is that with the increased overlap and lift is that I am getting a reduced vacuum signal in the lower portion of the rev range; a #3 slide could fix that.
What do the Combats run for carb internals, my engine should be a peer of one of those, just 100cc larger???
I started out with 260s and it felt flat beyond 3/4 throttle.
I went to 250s, then 240s and today 230s, gets better each time and it was to signing off at 85-90, with the 240s, today, with the 230s it pulled through 100 and would have kept going (slowly).
I have been watching for, but I am not experiencing a lean surge, on abrupt throttle shut down from WOT beyond 6000 RPM, but I am reluctant to go to 220s. I am also thinking that the engine is still breaking in so I am also reluctant to flog it for extended periods. I am going to try the #3 slides and see if it will get off the line with out slipping the clutch as much as I do now and I may try the 220s, but that just seems too lean even if I'm already close to that now. What I really need is some dyno time and see what the sniffer tells me; once I get 1500 miles on the engine I'll do that, no more guessing.
I am very happy with the performance envelope between 30 and 70 and may just stop trying to make it into a Ducati. The Norton is very responsive to the throttle going up or down through the gears, it is a pleasure to ride and it still amazes me to think that it is 34 years old...
Thanks for all the advice, it makes me think that I am on the right track.
RS
