gearing vs speed changes

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ross46
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gearing vs speed changes

Post by ross46 » Wed Dec 04, 2013 12:55 pm

now that its coming to winter im trying to get my bike A, working! and B a bit tamer for the wet. sound like a pussy but i cant be bothered with the back stepping out all the time when trying to commute. so as a cheap way to achieve that ive been looking at going up a tooth on the front sprocket to calm the acceleration. put the figures into http://www.gearingcommander.com/ and it says that top speed will be 155?! does that sound right? i know the maths cant be challenged as its all fixed variables. is that really achievable or will the bike not want to do it? what is the ACTUAL redline of a zxr? it says 14500rpm on the clock but does anyone know the actual figure? (why does it come up as 13000 on gearing commander?) am really interested if the bike would actually DO top speeds matching 600's or looking again 1000's! doubt with +3/-3 the bike would actually pull away never mind reach 196!! any opinions on gearing changes and results would be appreciated

noodleface
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Re: gearing vs speed changes

Post by noodleface » Wed Dec 04, 2013 2:19 pm

gearing commander has 13000 as that is the rpm at which your bhp is at maximum, your torque peaked/flattened a few thousand rpm before, its the rpm at which you should shift up if trying to maximise acceleration.

155 is a theoretical maximum if your bike could hit 14,800rpm with the gearing you have specified, and if the tyres have the same circumference etc...but due to the power of the bike and general limitations of a small machine dont expect to hit anywhere near that, especially if you have "up" geared it.

also the speedometer is way off, 140mph on the speedometer means you are doing about 130mph actually (i.e. if you recorded by GPS).

-nf
Last edited by noodleface on Thu Dec 05, 2013 9:40 am, edited 1 time in total.

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KwakKwak
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Re: gearing vs speed changes

Post by KwakKwak » Wed Dec 04, 2013 2:25 pm

ross46 wrote:i cant be bothered with the back stepping out all the time
Kawasaki traction control system :smt002
Throttle.JPG
From memory a one tooth change on the engine sprocket equals 3 on the rear, which is obviously quite drastic.
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Does the low seat height reflect the low intelligence? Easier to get an asshole onto.

cargo
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Re: gearing vs speed changes

Post by cargo » Wed Dec 04, 2013 3:35 pm

wind resistance dear boy..................wind resistance.

ross46
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Re: gearing vs speed changes

Post by ross46 » Wed Dec 04, 2013 4:38 pm

nf, at 13000 rpm the bike may produce more hp but the top speed will be higher at 14500 rpm. and 155 is the theoretical maximum @ 14.5k, max at 13k is 138mph with 45/16 gearing. and cargo im only small! and with a double bubble screen. i'll test it and put up my results with a gps speedo, on private land of course!

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