20" Bmx to electric
- Thread starter Fvrdol
- Start date
Chalo
100 TW
E-HP said:
That's definitely what I'd do if I wanted to ride a BMX e-bike (like a trained circus bear).
This one got both battery and controller in a handlebar bag. Very tidy installation but also a very dreadful little bike. Solid tires, huge rear rack with a big milk crate, just intense suckage all around. Built for a loony garden gnome of a man who knew exactly what he wanted, that nobody in their right mind would want.
Chalo
100 TW
E-HP said:
Coaster brakes are not especially powerful or sensitive, but they are consistent and dependable. This guy wanted one instead of the U-brake his frame was set up for, but I convinced him to install a dual pivot caliper brake in front when he came to pick up the bike. I think he'll be fine for the 20ish mph his bike is capable of, and the 12-15 mph that can be tolerated on solid 20" tires.
Chalo said:
I could only brake well with my right foot. Like when sliding sideways and skidding to a stop was always easier turning left, supporting the bike with my left foot, and slamming on the brakes with my right foot. I could never get used to the other direction.
Chalo
100 TW
E-HP said:
When I ride my coaster brake bikes, I can brake with the right, the left, or even with the pedals at the top and bottom. I just think "pedal backwards" and it does what I want. But I usually go for the front handbrake first because my hand is better at that.
I'm still considering spending $25 for to test whether a freewheel threaded side cover can replace the plain one on a front hub motor. It seems like it might be a tight clearance between the freewheel and dropout, even with a single speed. Not sure how the axle and bearings will line up.
Even going this route, there's still 14mm axle dropouts to deal with. For that, I was thinking of using 1/2" angle iron to make clamping dropouts, and skip the axle bolts.
Even going this route, there's still 14mm axle dropouts to deal with. For that, I was thinking of using 1/2" angle iron to make clamping dropouts, and skip the axle bolts.
Chalo
100 TW
E-HP said:
If you add 5mm of spacer washers to each side of the axle (and the axle is long enough to accommodate the extra spacing), everything should fit okay. That's assuming that the new side cover geometry is identical apart from the freewheel thread.
Even a disc brake should work, because the normal front locknut-to-disc-mount spacing is 10mm but rear spacing is 15mm. That doesn't help BMX bikes that don't have disc caliper tabs, though.
Elektrosherpa
1 kW
- Joined
- Feb 7, 2021
- Messages
- 386
With mine (equipped with a 350 W front hub motor and a 15 Ah 36 V battery I can go way more than 25 kms.
Never really tried how much, because my normal tours with the hound are shorter,
but I definitely can go my standard 16-km-tour twice with one charge.
And then the battery is still not empty.
Never really tried how much, because my normal tours with the hound are shorter,
but I definitely can go my standard 16-km-tour twice with one charge.
And then the battery is still not empty.
Chalo
100 TW
Unless you're an unusual size, you will use about 16 watt-hours per km to travel at 32 km/h. That means you will consume about 400 Wh in 25 km. But you should have at least 50% more than that available, so you don't have to run the battery all the way down, and so it will keep doing its job as it ages.
600 Wh ÷ 37V = 16.2 Ah
600 Wh ÷ 48V = 12.5 Ah
If you go faster than 32 km/h, you will use more Wh/km. If there are hills, you will use more. If there are starts and stops, you will use more. If there's wind... you get the idea.
It's best to have more battery than you need, because the battery will have a longer lifespan that way.
600 Wh ÷ 37V = 16.2 Ah
600 Wh ÷ 48V = 12.5 Ah
If you go faster than 32 km/h, you will use more Wh/km. If there are hills, you will use more. If there are starts and stops, you will use more. If there's wind... you get the idea.
It's best to have more battery than you need, because the battery will have a longer lifespan that way.
