Author Topic: Sprocket choices  (Read 998 times)

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suzukisam

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Sprocket choices
« on: March 30, 2007, 07:14:55 PM »
I am looking for some advice on what I should run for sprockets.  Bike is a 77 CB750 K7 and currently running a 15T / 41T (stock) sprocket combination.  I am replacing these and the chain and am looking for some advice on what benefits there are to the other combinations of sprockets.  I found this chart but they are only numbers to me and does not really make sense to me.
any advice would be greatly appreciated.
Marc


Gear Ratio
         14  15 
43  3.07  2.87 
41  2.93  2.73 
38  2.71  2.53 

Offline Sam Green Racing

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Re: Sprocket choices
« Reply #1 on: March 30, 2007, 07:27:19 PM »
2.73 is the ratio that your gearbox is turning in relation to your back wheel.

If you change your sprockets to 18 48, the ratio will only be slightley different.(2.66)

The advantage to this is, your chain will be traveling at a much slower speed for the same amount of turns of both gearbox and rear wheel.

The chain and sprockets will last you longer and provided you maintain them you are unlikley to have a chain snap and damage your gearbox like they did in the early days on similar gearing set up.

Sam. ;)
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike

upperlake04

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Re: Sprocket choices
« Reply #2 on: March 30, 2007, 09:16:16 PM »
 To add to Sams' post, a sprocket combination that gives a  lower final ratio than your stock 2.73 will mean your bike will  travel at a higher speed for any given rpm. This could be beneficial if you want less buzz at highway cruising speeds.  A higher final ratio will allow quicker acceleration from stops but at the expense of top end speed.
 A google search for 'motorcycle gearing calculator' will show several handy sites.

Offline Sam Green Racing

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Re: Sprocket choices
« Reply #3 on: March 30, 2007, 09:20:43 PM »
Hi Dave ;)
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike

upperlake04

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Re: Sprocket choices
« Reply #4 on: March 30, 2007, 09:25:46 PM »
Howdy Sam ,   I quess I must have got that last part right then  :)

Offline Sam Green Racing

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Re: Sprocket choices
« Reply #5 on: March 30, 2007, 09:32:53 PM »
Yes Dave but the lower the number goes, the higher the gearing ;D ;D ;D ;D the higher the number the lower :D :D :D :D :D :D

You're still right ;)

Sam. ;)
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike