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[grofcvo]

Hey guys what is the stock cvo rk '14 final gear ratio on belt drive.
Want to install chain but want to have bike little bit quicker from start (I know there is mod to change front pulley from 32 to 30T .... easier to go with chain. )
tnx

[grc]

The rear sprocket is 68 teeth, and of course the trans output sprocket is 32 teeth.  That makes the final drive ratio 2.125:1

Jerry

[grofcvo]

I don't know how they calculate this , but remember saw somewhere if you lower front pulley to 30T and leave rear 68T ... you got close to 3. something or am I wrong.

[Para Bellum]

68 divided by 32 (68/32) = 2.125 so ratio is  2.125:1

68/30 = 2.267 so ratio is  2.267:1

So, not too close to 3.0:1, but it is a 6.7 % lowering of the ratio: 2.267 - 2.125 = 0.142; then divide 0.142 by 2.125 (original ratio) => 0.142/2.125 = .067 = 6.7%

[grofcvo]

tnx to clarify this (Y)

[Para Bellum]

YW

[grc]

grofcvo, be careful not to mix up the rear drive ratio with the overall gear ratio.  For instance, the 2.125 ratio I mentioned is strictly the ratio from the trans output shaft to the rear sprocket.  The total overall ratio, however, has to account for the other gear ratio's as well.  For instance, the primary ratio times the trans ratio times the rear drive ratio (final ratio) equals the overall ratio.  In the case of this RK, that would work out to 2.875 in sixth gear.

Primary:   46/34 = 1.353
Trans in  6th:    = 1.000
Final:      68/32 = 2.125

1.353 X 1.00 X 2.125  =  2.875

Now substitute a 30 tooth trans sprocket, and the Final Drive ratio becomes 68/30 = 2.267  and the overall ratio becomes 1.353 X 1.000 X 2.267  =  3.067

In other words, in those threads where the ratio changed to about 3 to 1 when they changed the trans sprocket, they were talking about the overall ratio, not just the final drive ratio.

Hopefully that all made sense.

Jerry

[grofcvo]

grofcvo, be careful not to mix up the rear drive ratio with the overall gear ratio.  For instance, the 2.125 ratio I mentioned is strictly the ratio from the trans output shaft to the rear sprocket.  The total overall ratio, however, has to account for the other gear ratio's as well.  For instance, the primary ratio times the trans ratio times the rear drive ratio (final ratio) equals the overall ratio.  In the case of this RK, that would work out to 2.875 in sixth gear.

Primary:   46/34 = 1.353
Trans in  6th:    = 1.000
Final:      68/32 = 2.125

1.353 X 1.00 X 2.125  =  2.875

Now substitute a 30 tooth trans sprocket, and the Final Drive ratio becomes 68/30 = 2.267  and the overall ratio becomes 1.353 X 1.000 X 2.267  =  3.067

In other words, in those threads where the ratio changed to about 3 to 1 when they changed the trans sprocket, they were talking about the overall ratio, not just the final drive ratio.

Hopefully that all made sense.

Jerry

Tnx Jerry,
That is what I was looking for, saw this on a web and couldn't figure out how they do this ..
= 2.87 stock ratio
= 2.97 ratio
= 3.04 ratio
tnx.