43t rear sprocket and other parts-

[Shibumi]

I can't wait to get it out and let it run, this was just a ride home across town!

Feels like it has 20 more horsepower, just amazing how much difference the leverage increase provides!


Any math geniuses in the crowd? Compared to a stock geared bike with a 250 lb rider, how much % advantage do I have in acceleration with 43t rear at 170 lbs?

This might help with your calculations Shibumi, depending on what you are looking for.

Ahh, speaking of math geniuses...

Actually I was thinking more like what percent advantage a 43t has in acceleration over a 40t (43/40, or 7.5% more leverage?), 670 lb bike & rider vs 750 lb (11.11% less mass to accelerate?).

Are there variables I'm missing, or is there an 18.61% advantage in acceleration when drag racing these two bike/rider?

170 lb rider with 43t
250 lb rider with 40t

 

[runeight]

If my memory serves me correctly it was around 500 rpm increase per tooth.

Example:

40/3000rpm (given speed)
41/3500rpm " "
42/4000rpm " "

r8

 

[Spike]

So... since throttle position equals RPM does this mean that the throttle becomes less sensitive  but outputs more torque at any given range?  So I will need to give it more thottle to move but that throttle will accelerate me faster?

 

[Shibumi]

If my memory serves me correctly it was around 500 rpm increase per tooth.

Example:

40/3000rpm (given speed)
41/3500rpm " "
42/4000rpm " "

r8

Did the gear calc, shows:

75 MPH at 4000 RPM with 40t
75 MPH at 4300 RPM with 43t


More like 100 RPM per tooth in top gear.

Not too bad.

 

[Spike]

AM -->

1345538[/ATTACH] AM]

I can't wait to get it out and let it run, this was just a ride home across town!

Feels like it has 20 more horsepower, just amazing how much difference the leverage increase provides!


Any math geniuses in the crowd? Compared to a stock geared bike with a 250 lb rider, how much % advantage do I have in acceleration with 43t rear at 170 lbs?    

This might help with your calculations Shibumi, depending on what you are looking for.

Ahh, speaking of math geniuses...    

Actually I was thinking more like what percent advantage a 43t has in acceleration over a 40t (43/40, or 7.5% more leverage?), 670 lb bike & rider vs 750 lb (11.11% less mass to accelerate?).

Are there variables I'm missing, or is there an 18.61% advantage in acceleration when drag racing these two bike/rider?  

170 lb rider with 43t
250 lb rider with 40t

Not taking into consideration the coefficient of friction and drag I am thinking this:

Power = Mass (lbs.) x Acceleration (feet per minute) x square root {
(initial velocity squared (in feet per second squared)) +
2 x acceleration (feet per minute) x
(initial velocity + final velocity) / 2) x your time delta (number of seconds elapsed)
}

Something doesn't look right but I can't put my finger on it.

This should give you power in foot pounds per minute taking into consideration a constant acceleration. This is unrealistic for a motorcycle but the closest I can come up with off the top of my head.

Plugging in values for each rider's prospective weight should give you the difference in power produced over time.

I am trying to figure out how upping the teeth will play into this but I think that will need to take into consideration the new gearing ratios produced. I am not quite sure though.

Ok, out to mow the lawn. Enjoy!

 

[SANDFLEA85]

If my memory serves me correctly it was around 500 rpm increase per tooth.

Example:

40/3000rpm (given speed)
41/3500rpm  "         "
42/4000rpm  "         "

r8

Did the gear calc, shows:

75 MPH at 4000 RPM with 40t
75 MPH at 4300 RPM with 43t


More like 100 RPM per tooth in top gear.    

Not too bad.

do you have a speedohealer on there? when i changed from 40 to a vortex 42T I was off 18%

 

[LA Busa]

I run a 43 at the track - lets a guy run in a higher gear in turns.

Cant stand the higher RPMs on the street and I switch back to the 40.

To each his own!