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Old 08-04-2011, 10:31 AM   #19 (permalink)
jkv357
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Quote:
Originally Posted by Old Mechanic View Post
At a tach reading of 6k RPM the vehicle speed is 57MPH. 6th gear can be used down to 3k RPM, but no acceleration, just to maintain speed. Acceleration at 3k RPM is good in the first 3 gears but in the last 3 gears you really need to be at 3500 or more RPM (engine warm of course). I think the gearing is comparable to the Rebel with 80 MPH about 8400 RPM (CBR) but top speed is much higher with the 10.5k red line. I have seen some videos of speedo readings of over 165 KPH, probably for a short 150 pound rider in a full tuck behind the windshield. Most times I accelerate from 4 to 5k RPM then shift, higher if I want to get to speed faster.
(SNIP)
I wonder what dropping 1000 RPMs would do to cruise MPG? Changing to a 1 tooth larger countershaft sprocket would give you about a 500 RPM drop. That's a quick/cheap way to try it. If that felt good and you wanted more you'd have to get a rear sprocket with about 3 less teeth to drop another 500.

Even the countershaft sprocket could be a bit too much gearing for start and stop riding, although the CBR does have a good amount of torque for it's size.

You could look at a dyno chart and see just how much the torque drops as you go down in RPMs.

Let us know how it's going so far.


Jay
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