Hi everyone, planning a conversion...

[bbqforce10]

Hi everyone,

This is a superb site, I've spent the past few days reading and reading, so much great info and advice.
I think I'm starting to work out what I need, but not quite 100% and would appreciate some advice.

I'm planning on building an electric bike as a commuter primarily, with the occasional off road trails as well.
I've got a steel framed On One Inbred 29er that I want to convert.
My commute is 11 miles each way, with a 700ft climb in total (fairly big hills at each end of the route). I'm 85kg.
I want to pedal but want some assistance on the hills.
I do the commute at the moment on a normal bike, but it is tiring and I'm not fit enough to do it every day, in fact I only do it occasionally. The plan is with an ebike I will do it most days.

From what I have read, I think a mid-drive could be the best for me. I'm thinking a BBS02. Is that a good choice? I have read in some places that the BBSHD is much better, but is this overkill for my needs?

Re batteries, I have access to low cost 48 volt and 80 volt batteries. I work for a garden machinery company and we use these batteries in our lawnmowers and garden tools. They are only 4 or 5Ah, but I'm thinking that I could connect a couple of 48 volt batteries in parallel. Would this work for my needs?

I'd really appreciate any views.

I can't wait to get the kit ordered and the project under way!

Thanks

Adam

 

[Deleted member 4366]

Connecting lithium batteries is not as easy as lead ones because they have a control board inside, which manages the charging and discharging. It can be done, but without changing things, you have to make sure that each battery is approximately the same voltage when connecting it to another. Also, it's very important to disconnect them from each other when charging, so if you want to use three or four, you'll need three or four chargers too. All things considered, it saves a lot of messing about if you use a proper ebike battery, that will give you a much neater installation.

I wouldn't use a crank-drive bike for commuting. I commuted for a few years 30 miles a day on hub-motored bikes, which were much more suited to it. I also had a lot of climbing. I think it was something like 600ft on the way back and 300ft on the way there. I tried a crank-drive bike for a few weeks, but I could see only disadvantages compared with hub motors. All those bikes were 36v. 48v gives the same motors the potential for more speed and power. I weigh 100kg. At only 85kg, just about any cheap hub motor will make your journey easy, especially at 48v.

My preferred setup for commuting would be A 201 rpm 36v Q128H with this 48v battery and controller:

https://bmsbattery.com/ebike-kit/776-q128h-48v800w-rear-driving-e-bike-motor-wheel-ebike-kit.html

https://bmsbattery.com/ebike-battery/774-48v116ah-case-08-bottle-panasonic-battery-pack-battery.html

The only thing with BMSBattery is that they get the speeds mixed up, so you have to tell them that the 201 rpm is very important. You'd also need to change your gearing to suit- easiest to go down to a 7-speed DNP freewheel. If you don't want to do that, then you should get the 36v 201 rpm Q128C motor, which would keep your present gearing.

Some people use the BBS02 for commuting and appear to be happy with them. There's a lot of people that'll tell you that a CD is the best thing since sliced bread, buut not many of them commute more than 20 miles a day. Perhaps someone that does will chip in with sensible comments.

 

[Woosh]

hello bbqforce10,
if you don't want to buy directly from China, I can supply a BPM kit on 700C rim, 15AH HL battery that goes to the downtube, quite neat wiring if not neater than the bmsbattery kit where all the supplied cables are way too long.
Although not as fast as the Q128H on 48V, the BPM pulls exceptionally well on hills.
For a general idea, please visit:
http://wooshbikes.co.uk/?hubkits

If you have any question, just ask.

 

[Swinman]

As you say you can get your own battery then just plug one in at a time but take 2 or 3 with you, the amp hour will be the same but charging will be easy unless you only have the one charger, as you have had a look around the site you must have seen the macallister post on how to make one battery work with any bike , good look on build , all the best

 

[bbqforce10]

Thanks d8veh for your detailed reply......ok, I am reconsidering my options now.

Thanks also Woosh.

I hadn't found that post Swinman, but have read it now. Very interesting, thanks. I want to try something similar as I have basically got access to free batteries, so worth a try to start with!