I'm interested in this also.
What I'm feeling on my 2002 turbo (220hp) is that the gearing is much more complicated than N/A gearing since being geared higher allows you to open the throttle more and load the turbo to reach a given speed.
So the term "too aggressive" might not be the best thing to call it as opening your throttle further and pulling longer in a gear might actually feel faster.
Put another way, you are getting the turbo to work harder and longer in each gear so I think gearing becomes deciding how many gears you want the front end to lift @ WOT. For me, I think 3 works.
When I bought my bike, I had 18/39's on it. Because the sprockets were worn, I had them replaced on the road and all that were available were stock (if 17/40 is stock). The mechanic said it would feel faster but really it didn't because I had to be more conservative with my throttle and shift more often.
One has to consider that not all riding is WOT but the turbocharger likes throttle, so how is that balance achieved?
I have a T3/T4 turbo that starts to boost between 5500 and 6500rpm.
I use my bike as a commuter and canyon bike and now I'm thinking about getting a smaller turbo that spools @ 3000ish and going back to the 18/39T gearing.
The idea is to have a bike that gets into boost faster and stays in boost longer. 300hp is my goal just like yours.
I'm at stock wheelbase by the way and plan to keep it there except for a few weeks of drag racing per year.
It seems to me that once one has settled on a target HP, that there is no reason to have a turbo on a bike that can make more than that, and also no reason to have gearing that keeps you from using that HP because you just spin tires or wheelie. It's just more shifting to do and more critical throttle control to worry about without actually gaining much actual acceleration.
I am interested in what the more experienced board members suggest, but my naive viewpoint at the moment is that I will go back to 18/39T at my next swap and increase Boost/HP if I want to go quicker.
Sean
