I tried 46, and for The street is useless way To short, trust me.
For a track, it would only work if there is a quarter mile straight, anything longer and it will top out
Now i am in a 43, and The bike feels good, but i am preatty sure it doesnt have enough power to use a 42, unless you weight 100 lbs
Maybe the lucky Number is 44, wish i was going to use, but my dealer put The 43 by mistake
Well, I'm not here to convince you Ryan Just passing on my experience.
I changed it to keep from needing to shift elsewhere on the track and ended up gaining top speed.
-Sean
PIR has the insane long front straight. 41 sounds crazy.
Just ran my RC390R Cup Bike at AHRMA event at Thunderhill had a 45T back everyone else had a 43T. 45T did not work just ordered a 43T have Corsa 140 tire on the back. Biggest change I made when I got the bike is installing a STM slipper clutch and added the power command quick shift. I use the GP shift pattern-4 in the rear nets a top speed of 119-120 at the rev limiter if you can get there.
The more important number is 9200 RPM at 110mph, you are right in the peak of the power before it starts to fall off.
I would much rather go +1 on the front but no one is selling that yet.
Looking at stock bike dyno graphs the power is all from 7k to 9k and drops off fast on either side. In that range you have 23ft/lb of torque by the time you reach the 10k rev limiter torque drops off to 18ft/lbs.