# Electric Bikes - Small Geared hub motors speeds (RPM & mph)

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chas58
04-08-13, 12:13 PM
Small Geared hub motors speeds (RPM)
Voltage is 36 volts, wheel is 26”/700c unles otherwise indicated

Ok, that add that keeps poping up on the right ---->
makes the table hard to read, so I'll move the table to the second postition here...

chas58
04-08-13, 12:14 PM
Small Geared hub motors speeds (RPM)
Voltage is 36 volts, wheel is 26”/700c unles otherwise indicated

Generic speed table
TOP SPEEDS & Range (from Papa motors)
309370
Motor Type - Top Speed - Top Range - Battery
24V/500W 16mph (26KM/H) 17 M (28KM) 24V20AH
36V/500W 19mph (31KM/H) 19 M (31KM) 36V15AH
48V/500W 26mph (43KM/H) 26 M (43KM) 48V15AH
48V/1000W 32mph (52KM/H) 26 M (43KM) 48V15AH
24V/350W(Geared Motor) 14.29mph (23KM/H) 12.42 M (20KM) 24V9AH
36V/350W(Geared Motor) 16.77mph (27KM/H) 19.25 M (31KM) 36V9AH

Cute Q100 speeds from user testing:
No-load motor speed A@ 36V with a 26" rim
Q100 36V "201" = 230 rpm
Q100 36V "328" = 273 rpm
Q100 25V "201" = 290 rpm

230rpm from the 36v 201 = 17.85mph
273rpm from the 36v 328 = 21.2mph
290rpm from the 24v 201 = 22.5mph
340rpm from the 24v 238 = 26.4mph

Q100 at 48V estimates (overvolting the motor)
300 rpm from the 36v 201 = 22mph *** sweet spot
355 rpm from the 36v 328 = 27mph
377 rpm from the 24v 201 = 29mph

Bafang BPM & CST (8fun) motor codes and RPM for 36v (from Bafang)
Code 08 is 378 rpm frt. and rear 48V slow-winds motors are Code 8
Code 09 is 335 rpm (motor code 16(9))
Code 10 is 300 rpm BMS: 48V 500w rpm393, rear, code 10 .
Code 11 is 280 rpm BMS: 48V 500w rpm393, Front. code 11.
Code 12 is 250 rpm
Code 13 is 230 rpm BPM 36V 350W front 201 rpm 26 (13) motor
Code 14 is 215
Code 15 is 205 rpm
Code 15 is 192 (BPM 36V500W 201rpm (code 15) )
For speed at 48V, use factor of 1.33 increase in motor speed.

MAC motor speeds (from http://em3ev.com (http://em3ev.com/))

6 turn high speed motor - 400rpm loaded at 36V; 6T - 45kph (28mph)
7 turn high speed motor- 350rpm loaded at 36V
8 turn standard motor - 320rpm loaded at 36V; 8T – 39kph (24mph)
10 turn torque motor - 255rpm loaded at 36V 32kph (20mph); 10T – 32kph (20mph) (STD KIT MOTOR)
12 turn low speed extra torque motor - 200rpm loaded at 36V; 12T – 25kph (15mph)

04-20-13, 07:32 PM
Most of this is moonspeak to me, but I'd imagine these tables will be quite handy.

How much effect would tire size have on the top speed of a geared hub motor? Wider tire = bigger diameter = higher gearing = higher top speed?

chas58
04-23-13, 10:29 AM
The information is invaluable when figuring out how to build a geared hub motor bike. It really should be a sticky.

For starters, this is a great place to start. It gives a reasonably conservative estimate of the type of hub motor, what size battery pairs good with it, and what you can expect for top speed and range:

312543

Motor Type - Top Speed - Top Range - Battery
24V/500W 16mph (26KM/H) 17 M (28KM) 24V20AH
36V/500W 19mph (31KM/H) 19 M (31KM) 36V15AH
48V/500W 26mph (43KM/H) 26 M (43KM) 48V15AH
48V/1000W 32mph (52KM/H) 26 M (43KM) 48V15AH
24V/350W(Geared Motor) 14.29mph (23KM/H) 12.42 M (20KM) 24V9AH
36V/350W(Geared Motor) 16.77mph (27KM/H) 19.25 M (31KM) 36V9AH

Tire size in general is not going to make too much of a difference, unless you make a big jump from 26x2.125 to 26x1.0 or 700c x 23mm to 700c x 52mm. Note that a 26" wheel with a 2.125" tire has roughly the same rolling diameter as a 700c wheel with a 23mm tires.

Wheel size will make a big difference. A 26" wheel will need a different motor (RPM) than a 20" wheel.

chas58
04-23-13, 10:44 AM
Also, keep in mind that slower RPM does NOT mean high torque. A fast wind and a slow wind of the same motor will have similar torque ouput, but putting too fast of a wind on a big wheel will cause the motor to operate inefficiently, and generate too much heat.

The torque comes from the current (amps), speed from the voltage.