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CB650R Can the revs in 6th gear be tamed

Patent

2020
CB650R ABS
May 19, 2020
Riding Since
2020
I want to meet the person maintaining momentum at 16mph in third!
 

Patent

2020
CB650R ABS
May 19, 2020
Riding Since
2020
In the name of science I gave this a go today. Turns out you can actually do 14mph in third
 

jef200

2019
CB650R ABS
Nov 28, 2021
Corsica
Riding Since
1979
I find the revs in 6th are far to high in relation to the speed, when Iam hitting say 55mph if I didnt look at the clock I swear I would be doing 80mph from all the comotion the pick gives out - Can a bigger sprocket on the rear do anything to calm this or am I stuck with it.
Too high? 55 mph in 6th is only 4000 rpm! Your engine can take 12000 rpm without suffering (if you have of course a good synthetic oil). It has been designed for that!
But if you really want to have less revs in 6th you should either put a bigger sprocket on the front (16 instead of 15) or a smaller on the rear (below 42). You will probably lose (but just only a little bit) in acceleration but you will save a bit more fuel at stable speed.
The standard secondary transmission ratio of the CB650R is 42/15. It gives you a speed of 132/134 kmh at 6000 rpm in the 6th gear (from my tachymeter).
I think this is fairly correct for normal ride on highways.
If you change the rear sprocket (a 40 instead of 42), you should be at 135/136 kmh..85 mph.
 
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