As the Hub Motor Turns and the Lipo Fire Burns. Gear reduction.
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https://woodgears.ca/gear/ratio.html
Being a self proclaimed genius may have been a little premature for a boast. However in five years maybe if I continue to learn I could appear to be a genius to any average person on the street who stops to admire one of my builds.
However one of the things that have bothered me as I could not fully grasp the concept is gear reduction. How the gear reduction addition to an electric motor works. This page I found has enlightened me. I can understand the mechanics now and I did take the old Currie original 450 watt motor apart and closely inspected it so now with this page I totally grasp the concept.
http://www.ebay.com/itm/48V-1800W-Electric-Brushless-Controller-motor-grip-ATV-Go-Kart-Scooter-1800-Watt-/142461529403?hash=item212b5e6d3b:g:-9kAAOSwIxZZfpiM
This motor to be used with any adult bicycle wheel 20" to 29" will require some type of gear reduction. 4,500 rpm is only going to work with maybe a 12 or 14" wheel with no gear reduction without being horribly over geared.
A 2 to 1 gear reduction would equal 2,250 rpm. A 3 to 1 reduction -1,500 rpm which would make sense and a 8 to 1 or 7 to 1 could possible use a freewheel 16 to 20 tooth depending on wheel size but the big blue wheel would be huge and look rdicelous on a rear bike rack.
Please correct me if I am wrong but if the small blue sprocket in the diagram were an 11 tooth motor sprocket and the small green tooth were also 11 tooth then for 3 to 1 gear reduction the large blue tooth would need to be 33 tooth.
Obviously the large green tooth would be the wheel sprocket if I were to build this.
Now a 34 tooth wheel sprocket should not be difficult to come by as a wheel sprocket directly hooked to the motor sprocket would probably be larger that the wheel which is impossible. The build would take place on the top of a rear rack with plywood bolted to it and the motor bolted down. The motor sprocket. (small blue sprocket) would connect to the large blue sprocket by short chain and small green sprocket connect to the wheel sprocket (large green sprocket) by longer chain. My first question is ; Is there any place to order the gears and hardware to build the gear reduction for a wheel sprocket. I would need to assemble it and all would need to bolt down to wood.
I am not sure I am going with this as I am not sure about spoke sprocket kits. I think spoke sprockets eventually bend the wheel as they apply pressure on the spokes on one side causing the wheel to bend , wobble and eventually pop off the chain. It would explain why the 24" cargo bikes rear 20" tire worked for months then started giving me problems. I did however come up with a possible solution for that which would require long enough bolts to extend to the spokes on the other side but two mounting kits would be required but they are cheap. The added benefit however would be twice the strength of just bolting to the spokes on one side.
The other option is a brand new rear Currie stock replacement which cost $120 that I finally broke down and bought as I kept failing using bent up 26" rims. The electric motor sprocket hooked up to a freewheel type sprocket was my original build on page one of the post and lasted 2 years and now the Currie uses a similar set up. Only if my idea to use all the spokes on the wheel instead of one side could I afford a new build especially if I order the 1,800 watt brush less kit. Since 1.000 watts = 30 mph gearing and 1,500 watts is 1,500 mph 1,800 watts should work for 37 mph.
Now if I were to add a geared hub for the rear wheel the power is being transferred to and 37 mph would be my top speed gear I would have two lower gear options for hills. One for moderate incline and another for steep.

I admit I have no clue how a geared hub motor works but if all this were to happen it would be equal or superior to the average mid drive. This is just a hypothetical project so saying I have excellent working brakes. A horn and lighting that none of my bikes currently have would it be something any of you would test drive. I was thinking the Haro V3 as it is not a down hill bike but is one of the best frames I have to build and has disk brakes on the front. Please let me know.
LC out.