I have a couple of 170mm dropout standard length (as opposed to midtail) fat tire cargo frames that I rejected from my commuter bike project.
I rejected these frames because I could not obtain tall enough gearing for commuting. The largest chainring that I could fit was a 46t and I only had room for a 3-speed freewheel because I insist on using a 50mm magnet rear hub motor.
3-speed freewheels definitely suck. They can be very difficult to remove. Of all the 3-speed freewheels available, sixteen is the least number of teeth that you can obtain on the smallest cog. I geared them as high as I could and my pedaling spun out at 18mph--boring!
The commuter bikes that I have are perfect for high speed riding, but being midtails with tall gears and a rigid fork, they would be ridiculous on steep single track.
There are great MTB trails in my city which call for a standard length frame, low gearing and a suspension fork. I am taking a suspension class which requires me to buy a Fox suspension fork, so with two leftover standard length frames and 170mm dropout Cromotors, as well as a suspension fork, I want to take this opportunity to build a couple of very low geared eMTBs.
The main reason that I made this post is because the lowest available gearing of a 23t single speed freewheel (http://www.bikeman.com/WIND-FWENO23....LoUaAuSq8P8HAQ) and Vuelta 20t chainring (https://www.amazon.com/Vuelta-Mtn-fl.../dp/B007YH7YV0) has me wondering if having more teeth in the rear than the front is reasonable.
I am used to riding with a 14t rear cog and a 58t chainring and I spin out at about 33 mph (a 58 X 14 setup yields a cadence of 80 at 33 mph on my 31.5" diameter tires).
A 20 X 23 setup yields the following cadences:
I rejected these frames because I could not obtain tall enough gearing for commuting. The largest chainring that I could fit was a 46t and I only had room for a 3-speed freewheel because I insist on using a 50mm magnet rear hub motor.
3-speed freewheels definitely suck. They can be very difficult to remove. Of all the 3-speed freewheels available, sixteen is the least number of teeth that you can obtain on the smallest cog. I geared them as high as I could and my pedaling spun out at 18mph--boring!
The commuter bikes that I have are perfect for high speed riding, but being midtails with tall gears and a rigid fork, they would be ridiculous on steep single track.
There are great MTB trails in my city which call for a standard length frame, low gearing and a suspension fork. I am taking a suspension class which requires me to buy a Fox suspension fork, so with two leftover standard length frames and 170mm dropout Cromotors, as well as a suspension fork, I want to take this opportunity to build a couple of very low geared eMTBs.
The main reason that I made this post is because the lowest available gearing of a 23t single speed freewheel (http://www.bikeman.com/WIND-FWENO23....LoUaAuSq8P8HAQ) and Vuelta 20t chainring (https://www.amazon.com/Vuelta-Mtn-fl.../dp/B007YH7YV0) has me wondering if having more teeth in the rear than the front is reasonable.
I am used to riding with a 14t rear cog and a 58t chainring and I spin out at about 33 mph (a 58 X 14 setup yields a cadence of 80 at 33 mph on my 31.5" diameter tires).
A 20 X 23 setup yields the following cadences:
Comment