I am completely new to ebikes so would appreciate advice on all aspects relating specifically to building up an ebike for my beloved to commute on, though I do have a fair bit of experience building, repairing and renovating non assisted bicycles, up to and including building wheels.
My beloved's commute is about 13.5 miles for the round trip and 1000ft of ascent (22km, 315m ascent) according to Bikehike. The steepest gradient in a couple of places is around 12% and there is a 1.5mile hill setting off from home of around 5-8% gradient.
Definitely this will be a step through frame, but I would appreciate advice on all the following:
I am thinking along the lines of a mid drive kit by Bafang: but what power output would be best for a non cycling fit lady in her fifties with a 'comfortable' build, but a stated desire to get some gentle exercise out of the riding. i am aware of the legal implications if using a motor with more than 250W rated output.
I am thinking of using a SRAM P5 internal gear hub with hub brake that I have already 'in stock' built into a wheel: is this adequate, e.g. what sort of bottom end gearing should I be looking at for getting up the 12% bits mostly on motor power? Also what gearing suits the motor best at max speed on the flat? Plus will it shift OK with power assist, i.e. when my OH stops pedaling and/or releases the throttle lever will the motor quickly stop putting in the power- the hub does not like shifting under load.
The next question is the battery capacity: what would be a pretty much guaranteed capacity to cope with the above round trip commute, with recharge at home possible nightly? Also can I set up a charger to use Economy 7 at night? Bike will be in an integral garage with easy access to mains socket.
I am aware of the trend towards having the battery on the down tube but looks this will not work well with a step through frame that the user will definitely be stepping through, so will be looking for alternative battery placement: i imagine this would best be on a rear rack, so where can I get a rear rack battery, or can I just screw one of the bottle cage boss mounted ones commonly sold with the kits to a rear rack?
The front brake will also probably be a hub brake (Sturmey Archer 90mm) but are the brake levers with cut offs supplied with ebike kits compatible with these brakes that use 'standard' cable pull, as per canti brakes and caliper brakes, rather than the bigger cable pull of v-brakes? E.g. are they adjustable for cable pull like these are (shown in v-brake mode, changed to 'CR' cantiliver brake mode by moving the triangular widget in the top version, or moving the pivot point down in the the lower one):
Final question is re lighting: I use a dynamo hub for my own non assisted commuter bike and think it is great with German regulations approved LED lights, i.e. StVZO approved with K~xxx markings. I would use similar lights on the ebike but think it seems silly to have a dynohub powering the lights when there is a great big battery available. Non of the kits/batteries seem to have any kind of loom/cable to power lights so how to connect? I am happy to splice in some extra wiring if that is what is necessary but some guidance about how to would be much appreciated. Also do I need to use ebike specific lights or can I use any of the 6V dynamo LED lights I have in stock already, somehow powered from the battery?
My beloved's commute is about 13.5 miles for the round trip and 1000ft of ascent (22km, 315m ascent) according to Bikehike. The steepest gradient in a couple of places is around 12% and there is a 1.5mile hill setting off from home of around 5-8% gradient.
Definitely this will be a step through frame, but I would appreciate advice on all the following:
I am thinking along the lines of a mid drive kit by Bafang: but what power output would be best for a non cycling fit lady in her fifties with a 'comfortable' build, but a stated desire to get some gentle exercise out of the riding. i am aware of the legal implications if using a motor with more than 250W rated output.
I am thinking of using a SRAM P5 internal gear hub with hub brake that I have already 'in stock' built into a wheel: is this adequate, e.g. what sort of bottom end gearing should I be looking at for getting up the 12% bits mostly on motor power? Also what gearing suits the motor best at max speed on the flat? Plus will it shift OK with power assist, i.e. when my OH stops pedaling and/or releases the throttle lever will the motor quickly stop putting in the power- the hub does not like shifting under load.
The next question is the battery capacity: what would be a pretty much guaranteed capacity to cope with the above round trip commute, with recharge at home possible nightly? Also can I set up a charger to use Economy 7 at night? Bike will be in an integral garage with easy access to mains socket.
I am aware of the trend towards having the battery on the down tube but looks this will not work well with a step through frame that the user will definitely be stepping through, so will be looking for alternative battery placement: i imagine this would best be on a rear rack, so where can I get a rear rack battery, or can I just screw one of the bottle cage boss mounted ones commonly sold with the kits to a rear rack?
The front brake will also probably be a hub brake (Sturmey Archer 90mm) but are the brake levers with cut offs supplied with ebike kits compatible with these brakes that use 'standard' cable pull, as per canti brakes and caliper brakes, rather than the bigger cable pull of v-brakes? E.g. are they adjustable for cable pull like these are (shown in v-brake mode, changed to 'CR' cantiliver brake mode by moving the triangular widget in the top version, or moving the pivot point down in the the lower one):
Final question is re lighting: I use a dynamo hub for my own non assisted commuter bike and think it is great with German regulations approved LED lights, i.e. StVZO approved with K~xxx markings. I would use similar lights on the ebike but think it seems silly to have a dynohub powering the lights when there is a great big battery available. Non of the kits/batteries seem to have any kind of loom/cable to power lights so how to connect? I am happy to splice in some extra wiring if that is what is necessary but some guidance about how to would be much appreciated. Also do I need to use ebike specific lights or can I use any of the 6V dynamo LED lights I have in stock already, somehow powered from the battery?