Hi, I'm designing an electric motorcycle for myself to be used the same way I currently use my petrol motorcycle, ie for both city and country transport (ie road registered). At this stage, I need some advice on motor selection. The bike will be recumbent and moderately streamlined in order to increase range. For simplicity and cooling I plan to mount the motor on the swingarm fwd of the rear wheel. I don't want to use a hub motor due to the weight (particulary unsprung). This means there will be one or 2 gear stages depending on motor selection.
I am entranced by the Astro 3220 motors for their power to weight and volume ratios and because they are sealed. For highway speeds (up to 110 kph (68 mph) here in Aus) and say 5% grade, I'll need about 5kw continuous, which is well within the motor's capability. For that cruising speed, I assume I'll need gearing good for a top speed of about 130 kph (81 mph). My real issue then is getting sufficient low speed performance for the 2/3 of my usage, which is urban. For good urban riding I'll need acceleration sufficient to get me from 0-100 kph in under say 10 sec.
This requires much more torque. I see others have used the 3220 (eg Matt Schumacher and Bruno Poweeeeer) and obtained 14 kw per motor. This would be enough when geared appropriately. How do they get that much power? A 3 turn 3220 at Astro's 1 minute current rating would get close but would need to be geared down 14:1. I'm thinking Matex 7:1 (similar to the beautiful Dogati bike) and toothed belt to the rear wheel. I have not had success contacting Astroflight so far.
I'd like to avoid big blocks like Agni due to motor is in the unstreamlined lower half of the bike which actually uses most of the power in drag at 110kph. I'm interested to hear of your motor or other suggestions.
Thanks. Jamie.
I am entranced by the Astro 3220 motors for their power to weight and volume ratios and because they are sealed. For highway speeds (up to 110 kph (68 mph) here in Aus) and say 5% grade, I'll need about 5kw continuous, which is well within the motor's capability. For that cruising speed, I assume I'll need gearing good for a top speed of about 130 kph (81 mph). My real issue then is getting sufficient low speed performance for the 2/3 of my usage, which is urban. For good urban riding I'll need acceleration sufficient to get me from 0-100 kph in under say 10 sec.
This requires much more torque. I see others have used the 3220 (eg Matt Schumacher and Bruno Poweeeeer) and obtained 14 kw per motor. This would be enough when geared appropriately. How do they get that much power? A 3 turn 3220 at Astro's 1 minute current rating would get close but would need to be geared down 14:1. I'm thinking Matex 7:1 (similar to the beautiful Dogati bike) and toothed belt to the rear wheel. I have not had success contacting Astroflight so far.
I'd like to avoid big blocks like Agni due to motor is in the unstreamlined lower half of the bike which actually uses most of the power in drag at 110kph. I'm interested to hear of your motor or other suggestions.
Thanks. Jamie.
