drive ratio formula

To get the gear ratio you divide the bottom by the top to get the ratio ex 40/21= 1.90. the stock gear ratio for 00 SRX 700 is 38/23 or 1.65

there is this one from the Aaen's clutch tuning guide

Engine speed x sprocket pitch diameter
Gearing= _________________________________
Shift ratio x MPH x 336
 
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needaSRX said:
To get the gear ratio you divide the bottom by the top to get the ratio ex 40/21= 1.90. the stock gear ratio for 00 SRX 700 is 38/23 or 1.65

there is this one from the Aaen's clutch tuning guide

Engine speed x sprocket pitch diameter
Gearing= _________________________________
Shift ratio x MPH x 336
Click to expand...


How would you get the gear ratio of 40/21 with an 8 tooth driver instead of a stock 9 tooth driver? I was told it was 2.05! If you divide top gear into bottom gear it is only 1.905! What do you have to multiply 1.905 by to get 2.05? I was never very good at math lol !
 
Hi:
The normal gear ratio formula is based on a 9 tooth 2.52" driver.
To correct for 8 or 7 tooth 2.52 drivers you must divide the final ratio by 9 then multiply by the new tooth[2.52] driver.
IE: top gear : = 23
bottom gear: = 38
38 dived by 23 = 1.65: for 9 tooth drivers[normal]
Therefore if you switch to 8 tooth 2.52" drivers
1.65 X 9 divided by 8 = 1.86:1 final ratio
Make sense?
 
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Here.

MPH = (RPM/Gear Ratio) x (Driver Circumference/12) x (60/5280)

Gear Ratio is calculated by dividing the bottom sprocket by the top sprocket in teeth.

Driver Circumferences:
7 tooth = 17.64
8 tooth = 20.16
9 tooth = 22.68
10 tooth = 25.24
 
kirk700 srx said:
How would you get the gear ratio of 40/21 with an 8 tooth driver instead of a stock 9 tooth driver? I was told it was 2.05! If you divide top gear into bottom gear it is only 1.905! What do you have to multiply 1.905 by to get 2.05? I was never very good at math lol !
Click to expand...

40 divided by 21 = 1.90:1
1.90 X 9 divided by 8 = 2.14:1 final ratio
 
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when going from 9's to 8's I always divide the top into the bottom and then multiply by 1.13. Some say 1.12. It's actually somewhere in between, but it's close enough either way 99.8% of the time.
 
kirk700 srx said:
How would you get the gear ratio of 40/21 with an 8 tooth driver instead of a stock 9 tooth driver? I was told it was 2.05! If you divide top gear into bottom gear it is only 1.905! What do you have to multiply 1.905 by to get 2.05? I was never very good at math lol !
Click to expand...


I was told for a 22/40 gear ratio ...It all makes sense now! 22 divide into 40 x 9 divide by 8 =2.045 to 1 Thanks for clearin that up for me !
 
Is it better to have gearing below or above 2 if you want to play alot with hard acceleration, I trail ride to get to the riding areas (about 50/50).
So theoretically my ratio should be 2.43:1
(18t top, 39 bottom, 8 tooth drivers) Is that what came stock on the 01 Mtn lite, 8 tooth drivers? Thats what I'm assuming.
 
One question I have is how track height affect gearing.

Like going to 8t drivers but a 1.5" or 1.75" track from the stock what ~1" tracK?

If going to a taller lug height track is a gearing change necessary?
 
Track height shouldnt play a factor in drive because the drivers are just driving an endless belt... its basically like your car tires are the driver and the road is the track.
 
You should lower your gearing if you use a bigger lug track, if gearing is too low when you change the gearing and your over reving add some weight to your primary weights on tip! I could be wrong on this I am just learnin myself
 
WNYViper said:
Track height shouldnt play a factor in drive because the drivers are just driving an endless belt... its basically like your car tires are the driver and the road is the track.
Click to expand...

Ah that makes sense thank you for putting it in laymans terms!
 
klrgreenis said:
One question I have is how track height affect gearing.

Like going to 8t drivers but a 1.5" or 1.75" track from the stock what ~1" tracK?

If going to a taller lug height track is a gearing change necessary?
Click to expand...



Well If you are goin from 9 tooth drive to 8 tooth drive with gearing 18/39
Stock would be 2.16.1

With 8 tooth drivers will be 1.93.1

top/bottomx8/9=1.93.1
 
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