Here's the story of my electric bike. I posted some things before but in case you didn't read it or can't remember here's the whole story.
I started with a San Eagle electric folding bike that was advertised on Ebay but I bought it direct from the warehouse for £485.
Its performed well during the 9 months that I've had it and I think its a very good bike for the money, but I wanted to make it better so I added a few extras.
Alarm
Indicators
Horn
Wattmeter
Computer
Slick tyres
I then made it lighter by chucking the hidious heavy battery rack and put on a lightweight rack with the battery in a bag. Then I got a second battery for it for £160 to extend the range and put that in the bag as well. Then I wanted more climbing power so I changed the motor for a 350w Bafang BPM which I got for £40 part exchange for my old motor. It was much better but still didn't give enough power from the 250w controller so I soldered the shunt which made it better still but not enough. Then the fork dropout broke when tightening the nuts because the washers didn't fit properly, but I managed to find some Zoom DH forks for £3 at the boot sale that same day. These forks made the ride a lot better and have very strong dropouts so I was very lucky. I still wasn't happy with the power because my friend's bike had the same motor, but he was throttling up hills while I was pedaling hard and puffing, so I got a 350w controller, but it was hardly better and only gave 14amps, so I did the shunt mod and got it up to 25amps and now it has the power that I want at last. So this is how it looked.
Then I was bored because I couldn't think of any more improvements. It had enough power, all the add-ons that I needed, it was comfortable and reliable, it had a good range from the 20aH batteries now in parallel to provide the current and only cost about £750 total.
Then my son brought home a full suspension bike to sell for a friend and I sat on my chair in the garage pondering about how I could adapt my bike for full suspension. After many hours staring at both bikes I suddenly got an idea. £460 and a short amount of work and this is the result. Its powered by 5.2ah 44v lipos, which only cost £60. It weighs 21kg. It out climbs my friends bike now. It has a lovely soft ride with nice handling. It looks really nice to me and its not too easy to see that its electric. It hit 39mph freewheeling down a steep hill so can't have very much motor drag. In two words its brilliant. The only tricky bit was to get the disk to line up which needed a lot of filing of the caliper carrier.
My total outlay is now about £1200 but I have 25ahrs of battery and a complete folding bike to sell on ebay or facebook.
I'd like to say thanks to my friend D8veh, who used to be on this forum and he helped me with ideas, the wiring and soldering, fitting the disk, dished the front wheel to make the rim central to the forks and made the temporary battery carrier made of perspex. Later we'll make a nice proper fitting aluminium one when I can get some aluminium. That doesn't leave much really. Well at least I supplied the cash, made the tea and food and provided moral support. I only need to work out how to tell my nearest and dearest about the £400. She's on holiday at the moment.
Update. I've just competed my first rideout on it without any problems. 61 miles Telford to Bewdley and back along the Mercian way using only my 36v 20aH battery. The hills were very very steep between Bridgenorth and Bewdley. That part of the route is not for the feint hearted and would defeat most electric bikes, but my bike gets up hills like that without pedaling if I want, so the ride was very enjoyable. I'll post a writeup about that ride later. Also I can see more mods coming. Dave is working on a fully programmable controller interface which will a give it climbing power but at the same time limit the speed to 15mph to make it a bit more legal plus cruise control that works from the pedal sensor which I haven't fitted yet because its too fast.
I started with a San Eagle electric folding bike that was advertised on Ebay but I bought it direct from the warehouse for £485.
Its performed well during the 9 months that I've had it and I think its a very good bike for the money, but I wanted to make it better so I added a few extras.
Alarm
Indicators
Horn
Wattmeter
Computer
Slick tyres
I then made it lighter by chucking the hidious heavy battery rack and put on a lightweight rack with the battery in a bag. Then I got a second battery for it for £160 to extend the range and put that in the bag as well. Then I wanted more climbing power so I changed the motor for a 350w Bafang BPM which I got for £40 part exchange for my old motor. It was much better but still didn't give enough power from the 250w controller so I soldered the shunt which made it better still but not enough. Then the fork dropout broke when tightening the nuts because the washers didn't fit properly, but I managed to find some Zoom DH forks for £3 at the boot sale that same day. These forks made the ride a lot better and have very strong dropouts so I was very lucky. I still wasn't happy with the power because my friend's bike had the same motor, but he was throttling up hills while I was pedaling hard and puffing, so I got a 350w controller, but it was hardly better and only gave 14amps, so I did the shunt mod and got it up to 25amps and now it has the power that I want at last. So this is how it looked.
Then I was bored because I couldn't think of any more improvements. It had enough power, all the add-ons that I needed, it was comfortable and reliable, it had a good range from the 20aH batteries now in parallel to provide the current and only cost about £750 total.
Then my son brought home a full suspension bike to sell for a friend and I sat on my chair in the garage pondering about how I could adapt my bike for full suspension. After many hours staring at both bikes I suddenly got an idea. £460 and a short amount of work and this is the result. Its powered by 5.2ah 44v lipos, which only cost £60. It weighs 21kg. It out climbs my friends bike now. It has a lovely soft ride with nice handling. It looks really nice to me and its not too easy to see that its electric. It hit 39mph freewheeling down a steep hill so can't have very much motor drag. In two words its brilliant. The only tricky bit was to get the disk to line up which needed a lot of filing of the caliper carrier.
My total outlay is now about £1200 but I have 25ahrs of battery and a complete folding bike to sell on ebay or facebook.
I'd like to say thanks to my friend D8veh, who used to be on this forum and he helped me with ideas, the wiring and soldering, fitting the disk, dished the front wheel to make the rim central to the forks and made the temporary battery carrier made of perspex. Later we'll make a nice proper fitting aluminium one when I can get some aluminium. That doesn't leave much really. Well at least I supplied the cash, made the tea and food and provided moral support. I only need to work out how to tell my nearest and dearest about the £400. She's on holiday at the moment.
Update. I've just competed my first rideout on it without any problems. 61 miles Telford to Bewdley and back along the Mercian way using only my 36v 20aH battery. The hills were very very steep between Bridgenorth and Bewdley. That part of the route is not for the feint hearted and would defeat most electric bikes, but my bike gets up hills like that without pedaling if I want, so the ride was very enjoyable. I'll post a writeup about that ride later. Also I can see more mods coming. Dave is working on a fully programmable controller interface which will a give it climbing power but at the same time limit the speed to 15mph to make it a bit more legal plus cruise control that works from the pedal sensor which I haven't fitted yet because its too fast.
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