Hi all, hoping for some advice / input / critique on a build that I'm working on for myself.
Current plans are:
Bullitt acoustic frame (which I already have)
Grin all axle v3 rear direct drive motor, mounted via 142x12 through axle
Phaserunner v6
Cycle Analyst v3
Custom LiFePo4 battery pack under the cargo tray
Single speed drivetrain
All control via torque sensor (and analogue pot on the handlebars for varying this) and reverse pedal for regen
My general goals are:
Future expandability and hackability
Safety (I'm not overly keen on strapping my child onto the top of a DIY battery with more volatile chemistry)
Simplicity and low maintenance (hence SS drivetrain and DD instead of geared motor)
Exploiting regen braking (I'll often be making a mainly downhill run with more mass - my child - then climbing again without this for school dropoffs)
I've been riding predominately SS and fixed gear bikes for the past ~20 years so familiar and comfortable with the trade-offs there. The motor here is essentially for filling in torque from a standstill and helping get up steeper grades. Based in Australia so control is PAS only and tops out at 25km/h.
I had originally planned for a GMAC 10T and torque sensing BB, but after chatting with the folks at Grin and seeing some of the threads here have opted to avoid that due to the noise issues. The All-Axle is also more than enough power, despite being a little less efficient at low speeds due to the direct drive. The extra reliability, simplicity, and integrated torque sensor make it worth it (on paper). Also, while the Max45 SS looks excellent performance wise, I'm cautious of the visual impact drawing a little too much attention in a time where there is increasingly restrictive laws around higher power e-bikes here.
Keen on any guidance and comments for or against the above kit and general approach.
Current plans are:
Bullitt acoustic frame (which I already have)
Grin all axle v3 rear direct drive motor, mounted via 142x12 through axle
Phaserunner v6
Cycle Analyst v3
Custom LiFePo4 battery pack under the cargo tray
Single speed drivetrain
All control via torque sensor (and analogue pot on the handlebars for varying this) and reverse pedal for regen
My general goals are:
Future expandability and hackability
Safety (I'm not overly keen on strapping my child onto the top of a DIY battery with more volatile chemistry)
Simplicity and low maintenance (hence SS drivetrain and DD instead of geared motor)
Exploiting regen braking (I'll often be making a mainly downhill run with more mass - my child - then climbing again without this for school dropoffs)
I've been riding predominately SS and fixed gear bikes for the past ~20 years so familiar and comfortable with the trade-offs there. The motor here is essentially for filling in torque from a standstill and helping get up steeper grades. Based in Australia so control is PAS only and tops out at 25km/h.
I had originally planned for a GMAC 10T and torque sensing BB, but after chatting with the folks at Grin and seeing some of the threads here have opted to avoid that due to the noise issues. The All-Axle is also more than enough power, despite being a little less efficient at low speeds due to the direct drive. The extra reliability, simplicity, and integrated torque sensor make it worth it (on paper). Also, while the Max45 SS looks excellent performance wise, I'm cautious of the visual impact drawing a little too much attention in a time where there is increasingly restrictive laws around higher power e-bikes here.
Keen on any guidance and comments for or against the above kit and general approach.
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