Charles Laypool
Active Member
Im just trying to figure out what gearing is best for me with a jackshaft kit
If my motors Max rpm is 5500 and its internal gear reduction is 4.1 so my output sprockets rpm is 1341.4634146
So 10t to 17t is 1.7:1
(789.09612623 rpm)
17t to 10t is 1.7
(469.17419194 rpm)
10t to 44t is 4.4444444444
(105.49413453 rpm(at the pedals)
44t to 36t is 1.2222222222 (86.313382798 rpm(to rear tire)
Now if i calculate
Axle teeth / Pedal teeth = gear ratio.
Sprocket RPM / Gear Ratio = Wheel RPM (wRPM)
Tire circumfrence in feet * wRPM = feet per minute.
Feet per minute * 60 = feet per hour.
Feet per hour / 5280 = miles per hour.
1st----9mph
2nd-10mph
3rd-12mph
4th-16mph
5th-18mph
6th-21mph
7th-24mph
8th-27mph
Now i really hope im doing something wrong i ordered my shift kit im jus waiting to get it but i want to get best gearing and these results are crap someone enlighten me
If my motors Max rpm is 5500 and its internal gear reduction is 4.1 so my output sprockets rpm is 1341.4634146
So 10t to 17t is 1.7:1
(789.09612623 rpm)
17t to 10t is 1.7
(469.17419194 rpm)
10t to 44t is 4.4444444444
(105.49413453 rpm(at the pedals)
44t to 36t is 1.2222222222 (86.313382798 rpm(to rear tire)
Now if i calculate
Axle teeth / Pedal teeth = gear ratio.
Sprocket RPM / Gear Ratio = Wheel RPM (wRPM)
Tire circumfrence in feet * wRPM = feet per minute.
Feet per minute * 60 = feet per hour.
Feet per hour / 5280 = miles per hour.
1st----9mph
2nd-10mph
3rd-12mph
4th-16mph
5th-18mph
6th-21mph
7th-24mph
8th-27mph
Now i really hope im doing something wrong i ordered my shift kit im jus waiting to get it but i want to get best gearing and these results are crap someone enlighten me