Hi everyone,

 

I'm thinking of getting an ebike conversion kit for commuting and would like some advice about which one would be the right one for me.

 

first I'll explain my current situation and what I'm hoping to achieve by building my own ebike.

 

I have quite a long commute, 30 miles each way with a couple of steep hills but mostly flat. I currently have a 2016 Haibike Sduro (with the speed limiter removed) and a car and alternate between the two. I would like to cycle more often but find that it takes too long (1 hour 20 to 2 hours depending on conditions and how lazy / tired I am feeling). I have a 36v 14.5AH battery on it.

 

My plan is to get a more powerful bike by adding a motor to an existing MTB and get it classified as a two wheeled vehicle so I can legally do 28mph on it (i'm based in the UK).

 

I would like to be doing 28mph for most of the journey and get my journey time down to just over an hour each way.

 

I'm generally drawn to the Bafang motors, either the BBSHD or BBS02(b). The BBS02 seems attractive because it's slightly lighter but would the BBSHD potentially get me there quicker? Does anyone know which one would be more efficient on that kind of journey? Would i need an enormous battery to do 30 miles in one hour? what would be the optimum sized chain ring for this kind of journey?

 

I'm also a bit unclear about how the pedals integrate with the motor on the Bafang. I'm happy to put in a decent amount of effort with the pedals if it means a quicker journey and a smaller battery. If i was doing top speed would I struggle to pedal fast enough to keep up with the motor? If so would a larger chain ring help to solve that problem? On my Haibike I find that at around 25mph the pedals can't keep up with the motor and I can't contribute much.

 

I'd also consider a hub motor if people thought that was more suitable for this kind of journey.

 

I've attached a diagram showing the elevation of the route taken from google maps.

 

Any advice would be greatly appreciated as I'm finding the whole thing a bit bewildering.

 

Thanks!

I think a direct drive hub-motor would be a lot more reliable and suitable for that type of riding. All you'll get for pushing that much power through the chain and gears is a lot of inconvenience and cost.

I've no idea about getting things classified whatsoever

 

That said I have a small cheap geared hub motor (36v) that I can run with a 48v battery . That'll do 23/24 mph and has amazing torque for size (xf07 by mxus )

 

I also have a bbso2b (36v version ) . One can play with gears and controller settings

 

I use a 16t sprocket on rear (alfine 8 hub) and a 42t front ring. That'll do 25mph happily

 

I have a 17.5 ah pack of MJ1 cells. I can get 50 miles off road over the South Downs with that.

 

It will do 30miles on max all the time .

My 22 mile commute takes about 1 hour, running a bbs02 500w at maximum assistance. That journey almost completely drains my hailong 36v 17.5Ah eclipse battery

 

You’d therefore need to scale that Ah number up to get to 30 miles - a downtube + rack battery combo would do it

 

However I average 22mph - the extra power needed to average 28mph over 30 miles is probably unachievable with existing battery tech

Have a search on YouTube for vortex he’s just finishing off a home build ebike and will be putting it through the VOSA test, you have to put certified lights, indicators, brake levers, number plate etc

I converted my mountain bike using a kit supplied by Woosh bikes. Its been excellent! Maybe give them a call and see if they can help you?

Once you get beyond 20 miles each way, a 50cc petrol moped makes a lot more sense than a converted electric bicycle. It'll cost significantly less, be cheaper to run, more reliable, more comfortable, better grip, better handling, etc, etc. I can't see a single advantage that a converted bicycle would have.

+1 wot VFR400 said.

 

If you want to stick to BEV consider a Super Soco as it'll work for your height where it was too small for me at 6ft 3in. Or a Nui scooter if you want to hide behind a bit of screen. www.green-mopeds.com have a good selection [i'm not affiliated in any way]

Thanks for the excellent feedback everyone!

 

The main reasons I want an ebike rather than a petrol or electric moped / are as follows:

 

1. When I was commuting in the car everyday I was beginning to become a fat thin man. I'm essentially using the wasted hours in the car to exercise.

 

2. I live in a flat, I have an entrance hall which is big enough to store a couple of push bikes. If I stuck a moped in there I wouldn't be able to get up the stairs. Everyone I've spoken to who's owned a moped or motorbike has said that if you leave it one your driveway at some point it will get stolen. Also it probably wouldn't be good for it to be left out in the rain all year round.

 

3. At work I can take a push bike inside. While I have a parking space outside, I work on a busy industrial estate and if I had a motorbike it would probably just be a matter of time until some idiot reversed over it in a lorry.

 

It seems like perhaps going 30mph the whole way was a bit ambitious, I'd settle for a bit more speed but then that raises the question of whether it's worth going through the rigmarole with the DVLA for a few extra MPH.

 

It seems like i would be better with a direct drive hub motor rather than a Bafang mid drive. It does seem like the hub motors are lagging behind the mid drives at the moment in terms of the quality of the kits (even if the motors themselves are as well made). Also buying the kits through ebay seems tough as many sellers don't seem to go into much detail about the difference between the motors or the requirements of the bike. If anyone can suggest a good kit then that would be greatly appreciated.

 

I could just stick with the Haibike. While it's a well made bit of kit one thing that worries me is the built in obsolescence. the display recently broke and a replacement cost £70 and I had to order it from Italy. Probably when this one breaks it won't be possible to buy another one and the bike will be a right off. At least with the kits their modular nature means the parts are easier to replace. Even if an integral part of it breaks and can't be replaced then the bike frame and the battery would still be good.

Thanks for the excellent feedback everyone!

 

It's a noble intention and your right to follow through on that! Clearly as you have the Haibike at the moment you're not going into this totally blind. Your call on riding an a pedelec that's illegal - I'm certainly not against the idea.

 

If it helps, I've only just got into pedelecs having converted a heavy road bike with a Woosh 250w rear hub and 17am battery. I mention it as I'm moderately fit and have to work fairly hard to average 17mph on it over a flat 1hr ride to work. The conclusion: you're going to need to go illegal!

All solid reasons

 

Eclipse do a 48v hailong battery with 65 18650 cells - that will give you the most amount of energy this side of a custom battery

 

You’d need to dial down the current a bit from maximum to squeeze 30 miles, but an average 20mph should be achievable if you’re already a strong cyclist

 

You’d need to charge the battery at work before your commute home. A 3a charge for 7 hours should do it

Having the Haibike derestricted seems fine. It's hard to get it above 16.5mph where there's any traffic / pedestrians and it seems safe riding at 24mph on long straight bits of road. I can't usually catch up with people on racing bikes so the only thing that makes it more dangerous is the weight.

 

Riding a pedelec that will do 30mph and weighs significantly more seems like taking the piss so I would try to get it through the DVLA thing and have it classified as a moped.

 

I plan to keep riding the Haibike until the new ebike is built, working nicely and all the DVLA hoops have been jumped through.

 

Given that the world is facing an ecological crisis, the roads in the south east of england are becoming permanently gridlocked and air quality in London is pretty terrible you would think the government would be doing something to encourage ebike use.

 

It's a noble intention and your right to follow through on that! Clearly as you have the Haibike at the moment you're not going into this totally blind. Your call on riding an a pedelec that's illegal - I'm certainly not against the idea.

 

If it helps, I've only just got into pedelecs having converted a heavy road bike with a Woosh 250w rear hub and 17am battery. I mention it as I'm moderately fit and have to work fairly hard to average 17mph on it over a flat 1hr ride to work. The conclusion: you're going to need to go illegal!

Thanks for the recommendation.

 

I'm thinking that I would get a frame battery for shorter journeys then one of those large triangular batteries for my commute with the option of using both for a long journey (I have in the past ridden to my parents 80 miles away on the Haibike).

 

All solid reasons

 

Eclipse do a 48v hailong battery with 65 18650 cells - that will give you the most amount of energy this side of a custom battery

 

You’d need to dial down the current a bit from maximum to squeeze 30 miles, but an average 20mph should be achievable if you’re already a strong cyclist

 

You’d need to charge the battery at work before your commute home. A 3a charge for 7 hours should do it

Wouldn’t converting a road or gravel bike make more sense if you are going all out for speed/range? It will also look less suspicious if you are doing 25mph+ on a racer.

Wouldn’t converting a road or gravel bike make more sense if you are going all out for speed/range? It will also look less suspicious if you are doing 25mph+ on a racer.

 

 

Yes, I'm thinking if I get a hub motor then that would make more sense. I'm not massively keen on drop handlebars and the last bit of the ride is in the outskirts of London. I feel a lot more in control on an MTB in terms of manoeuvrability, stability and being aware of what's going on around me. It might just be what I'm used to though..

 

Aeorobars would be another option to improve the aerodynamics although I'm not keen on going at that speed without being in easy reach of the brakes.

Edited June 26, 20196 yr by Hilly

Yes, I'm thinking if I get a hub motor then that would make more sense. I'm not massively keen on drop handlebars and the last bit of the ride is in the outskirts of London. I feel a lot more in control on an MTB in terms of manoeuvrability, stability and being aware of what's going on around me. It might just be what I'm used to though..

 

Aeorobars would be another option to improve the aerodynamics although I'm not keen on going at that speed with being in easy reach of the brakes.

Before I found a used MTB to stick a rear hub in I tried a gravel bike like this:

 

https://whyte.bike/products/glencoe

 

It was a bit more comfortable and stable feeling than proper road bikes I’d briefly tried in the past, while being extremely quick off the mark. You could probably get a similar effect by putting an extra wide handlebar and thick tires on an old road bike.

 

Dammit I’m giving myself ideas now!

Before I found a used MTB to stick a rear hub in I tried a gravel bike like this:

 

https://whyte.bike/products/glencoe

 

It was a bit more comfortable and stable feeling than proper road bikes I’d briefly tried in the past, while being extremely quick off the mark. You could probably get a similar effect by putting an extra wide handlebar and thick tires on an old road bike.

 

Dammit I’m giving myself ideas now!

 

Thanks, I'll look into that. The thing that puts me off is that you can't reach the brakes when your hands are on the top of the bar. I'm sure there's some kind of custom brake levers you can buy that do that.

Thanks, I'll look into that. The thing that puts me off is that you can't reach the brakes when your hands are on the top of the bar. I'm sure there's some kind of custom brake levers you can buy that do that.

Well, that's generally advised anyway (a set of brakes connected directly to the motor to ensure that it also cuts out the motor). Your only challenge would be to how to fit them onto the straight part of the drop handlebar as it'll be wider than the brakes allow

Thanks, I'll look into that. The thing that puts me off is that you can't reach the brakes when your hands are on the top of the bar. I'm sure there's some kind of custom brake levers you can buy that do that.

You ride with your hands on the hoods, where you can reach the brakes and shifters with your fingers. You can get cable brakes with extensions that come along the bars. I have some, but they're terrible.

 

I think a gravel bike with a 48v 328 rpm Q128C rear motor and a 52V battery would give you an acceptable cruising speed, and with a battery with enough charge to go full power all the way (one way), it would still be lighter than your Haibike. The kit with a 52v 17.5Ah battery would weigh about 8kg. Look for a donor with hydraulic discs, which will be much more reliable for long distance commuting. They're a lot more expensive, but worth it. especially when you only have thin tyres and need to have good modulation to prevent skidding.

 

If you go with a direct drive motor and enough current to cruise in the high 20's, you'll need a massive battery, which will push the total weight up to at least 35kg, which will be very awkward to lift up any stairs.

I find the riding position of being bent forward with my head bent up uncomfortable and would prefer to ride in a more upright position in traffic.

 

I guess I could buy the bike and try to get used to it. if I couldn't get used to it I guess there's no reason why I couldn't put a flat bar on it.

 

You ride with your hands on the hoods, where you can reach the brakes and shifters with your fingers. You can get cable brakes with extensions that come along the bars. I have some, but they're terrible.

 

I think a gravel bike with a 48v 328 rpm Q128C rear motor and a 52V battery would give you an acceptable cruising speed, and with a battery with enough charge to go full power all the way (one way), it would still be lighter than your Haibike. The kit with a 52v 17.5Ah battery would weigh about 8kg. Look for a donor with hydraulic discs, which will be much more reliable for long distance commuting. They're a lot more expensive, but worth it. especially when you only have thin tyres and need to have good modulation to prevent skidding.

 

If you go with a direct drive motor and enough current to cruise in the high 20's, you'll need a massive battery, which will push the total weight up to at least 35kg, which will be very awkward to lift up any stairs.

I had a quick google and I'm not sure you can buy those motors in the UK. Mybe they're marketed under a different name?

 

 

I think a gravel bike with a 48v 328 rpm Q128C rear motor and a 52V battery would give you an acceptable cruising speed, and with a battery with enough charge to go full power all the way (one way), it would still be lighter than your Haibike. The kit with a 52v 17.5Ah battery would weigh about 8kg. Look for a donor with hydraulic discs, which will be much more reliable for long distance commuting. They're a lot more expensive, but worth it. especially when you only have thin tyres and need to have good modulation to prevent skidding.

 

 

Do you think this would be suitable?

 

Planet X London

 

 

 

Before I found a used MTB to stick a rear hub in I tried a gravel bike like this:

 

https://whyte.bike/products/glencoe

 

It was a bit more comfortable and stable feeling than proper road bikes I’d briefly tried in the past, while being extremely quick off the mark. You could probably get a similar effect by putting an extra wide handlebar and thick tires on an old road bike.

 

Dammit I’m giving myself ideas now!

Personally I’d go full suspension for 60 mile round trip. Suitable frames are getting hard to find, but not impossible

[mention=22954]Hilly[/mention] Q128C - only place that sells it, you won’t find it in the UK. I found BMS a pain to deal with but they got there in the end.

https://bmsbattery.com/motor/768-16765-q128c-135mm-500w-rear-driving-ebike-hub-motor-ebike-kit.html

 

AKM128CST - apparently the same motor, different branding. TBK much easier to deal with than BMS.

http://www.topbikekit.com/akm128cst-48v500w-rear-driving-hub-motor-cassette-motor-for-ebike-p-723.html

 

Yes that bike looks like the same kind of idea as the Glencoe.

Or maybe something like a Boardman hybrid if you can’t get used to the drop bars.