Johnny, have you tried em3ev in China, I found them very good at responding, and will probably place my order with them for the Bafang 8fun CD and battery when I have fully made my mind up.

 

Paul at em3ev is good to deal with and is a top chap, but bear in mind that if anything goes wrong he is on the other side of the planet and you could find yourself with a very long downtime...there are many reputable importers here in the UK and it would be far easier if anything goes awry to return your motor/battery to them...I personally, support our UK vendors and have not had a problem with warranties, returns or support from anyone I've bought from...Just my ha'pennies worth and I hope I never have to say I told you so;)

The EU regulation is not concerned with any of this . Their statement is that the power assistance on a continuous basis must not exceed 250w.

 

That's the bit you have wrong. The regulation is on "rated" maximum continuous power, not maximum continuous power.

 

The engineer does all the calculations and tests, so that he has a good idea about the motor's actual limits. He's then worried about reliability, so he builds a safety factor into his rating. He has to consider and end user that might be so ignorant that he tries to start the motor from a standstill on a steep hill, or a very heavy guy that wants to go up steep hills, in which case he will leave a considerable margin between the rating and the power or torque that the motor can handle if treated respectfully.

 

Bosch, Yamaha and Brose motors are running round about 20 amps at 36v. That's 800w from the battery. With 75% efficiency, that would be 600w of output power at the crank.

Paul at em3ev is good to deal with and is a top chap, but bear in mind that if anything goes wrong he is on the other side of the planet and you could find yourself with a very long downtime...there are many reputable importers here in the UK and it would be far easier if anything goes awry to return your motor/battery to them...I personally, support our UK vendors and have not had a problem with warranties, returns or support from anyone I've bought from...Just my ha'pennies worth and I hope I never have to say I told you so;)

 

 

Oh, believe me, I'd rather shop 'locally', but trying to get any consistent advice - or any advice at all, seems to be nigh-on impossible. No response from either of the two obvious places to buy mid-drive Bafangs.

 

Like I said, I'm seriously considering a move into this marketplace since it is clearly only going to grow. In my experience, the current providers just don't seem ready to do a professional job, certainly in terms of initial communication. My thoughts are that if it's proving fruitless now when I've got the money to spend, how cr@ppy will it be when/if I get problems down the line.

Wow, is it really that bad Johnny, Steve UK, seems to have found some decent vendors if he would like to share.

 

I did try a local firm to me, that mostly sells model cars and pit bikes etc, they were advertising the Bafang units on eBay, but not in the shop, they told me that there was no stock of the 250w 8fun CD units, and did seem taken aback that I had linked them with the eBay site, not rocket science really, although that was back in July, and they expected to have stock by November, but I have not been back since to find out, and to be fair I was not feeling the love from them!

That's the bit you have wrong. The regulation is on "rated" maximum continuous power, not maximum continuous power.

 

The engineer does all the calculations and tests, so that he has a good idea about the motor's actual limits. He's then worried about reliability, so he builds a safety factor into his rating. He has to consider and end user that might be so ignorant that he tries to start the motor from a standstill on a steep hill, or a very heavy guy that wants to go up steep hills, in which case he will leave a considerable margin between the rating and the power or torque that the motor can handle if treated respectfully.

 

Bosch, Yamaha and Brose motors are running round about 20 amps at 36v. That's 800w from the battery. With 75% efficiency, that would be 600w of output power at the crank.

The 2014 uk consultive document did refer to rated power but that term did not make its way into the final document the latest version of which is October 2016.

I do agree with your calculation that with if the motor was drawing 20a at 36v it will be consuming 800w , but that is not what the regulation demands.

 

 

I would agree with you that the prudent designer will follow the steps you have outlined and that will inform his her thinking in selecting gearing and torque.

 

The Irish statute law SI 412\2005 which would mirror the EU directive reads as follows " cycles with pedal assistance which are equipped with an auxiliary electric motor having a maximum continuous rated power of 0.25kW of which the power is progressively reduced and finally cut off as the vehicle reaches a speed of 25km/hr, or sooner if the cyclist stops pedalling. "

 

I apologise but it is easier for me to access Irish law. Although this regulation dates from 2005 , it is to the best of my understanding the current lwgal position.

I'm curious because the power to shift my 250lbs/113kg weight, plus the bike, is my main worry. Speed is a secondary issue, although it would be fun to be able to temporarily de-limit the thing, under appropriate circumstances.

 

I'm at the research stage at the moment, although I'm edging towards the crank driven motors as opposed to front/rear wheel motors for my conversion bike.

 

It seems that Bafang/8-Fun has the market pretty much sewn up in terms of crank kits, but where to buy is now becoming a concern, since no-one seems keen to respond to their potential customers! I'm even considering setting up my own conversion kit import and retail business, as there is very clearly an opportunity to do it better than that which seems currently available...

 

The 200 watt original power limit in the U.K. Was to let someone have the power equivalent assistance of a average fit man , with a speed limit that the nominal ave fit man could achieve. The pushing of limits by manufacturers means that the bbs01 can be set to 18 amps at 42 volts or just under 800 watts.

That is above the maximum continuous output of an elete athlete.

If you add in 150 watts from yourself you will climb hills like lance armstrong.

Using this much power will drain the battery fast but we are a little short on 20 mile 10% climbs in the uk.

Wow, is it really that bad Johnny, Steve UK, seems to have found some decent vendors if he would like to share.

 

OK RB...at the risk of putting any noses out of joint (and you lot drying my supply sources up lol)...I only buy my batteries from Jimmy at Inst Intl (aka BGA reworking) as his build quality is second to none, he certainly knows his onions (as you will learn if you ever get one of his physics lectures:D) and in the 2 times we've had a problem with his batteries (and we've had many) he's honoured his warranty and fixed them for free, he's even upgraded them with pure copper inter-connects (both of the broken batteries were used on DH bikes that take some massive hits/abuse/mud/etc and had split in half)...now here's the real "I don't want to upset anyone" bit...I've sourced my motors from Darren at Brighton eBikes (a member on here and top chap) and Eclipse Bikes in Gateshead, Darren is a dream to work with and a fellow eMTBer, but Eclipse can be slow to respond to emails and that can put people off. However, Eclipse deliver within the week if you order on the www, are consistently cheaper than any supplier I have found in the UK and their current stock are the latest BBSxxB with "improved" internals.

 

***Sits back and awaits flaming:p***

Thanks for sharing Steve, I am new to all this ebike stuff, but was aware of Eclipse, although the last time I looked at there website the 250w Bafang 8fun CD was listed as out of stock.

 

Why is this such a cottage industry, even more so regards batteries, it does not give a regular punter like me any confidence to buy.

 

You mention the latest BBSxxB, I guess you mean the ones with 8 mosfets instead of 6 or whatever it is.

 

Darren at Brighton Ebikes seems like a good call, but is there no one in Manchester supplying Bafang motors and batteries kit.

 

You obviously know your stuff, and have real life experience of builds, I may have to give you a call if that is possible, I can do the build myself, so may just want to pick your brains.

woosh have BBS01 and BBS02 in stock.

 

http://wooshbikes.co.uk/?cdkit

...as have Eclipse and they are the latest BBSxxB http://www.eclipsebikes.com/bafang-8fun-bbs01-drive-250w-motor-p-1102.html

Thanks Trex, the 500w model does interest me, although not UK street legal, which does put a downer on the whole event!

 

But let's not open that can of worms up again.

Well...have I stepped on a land-mine, or what!!??

 

It just so happens that one of 'the two obvious choices' has indeed got back to me this evening, so I know where my money is going now...This is clearly a very influential site!!!

 

All joking aside, I am really grateful for the helpful nature on here - I'm a bit humbled by it, to be honest - and impressed. Thank you!

Well done Johnny, which kit are you going for?

RB, the latest ones (denoted B) have different/supposedly better internals and they changed the mosfets in early 2015, there are still plenty of older ones about for sale though, so always ask your vendor for the engine code (should be NCR not ECR) as there's still loads of old ones for sale on ebay, etc.

 

Agreed on the cottage industry bit, but it's gaining momentum in the UK and in a few years will be quite a booming little industry from the conversations I've had with "normal" MTBers and motorbikers (my latest Norco DH build is for an ex 2x British Superstock Champion)

 

I'd be more than happy to share my limited knowledge and sources with you if you want to build your own, i'll pm you on here with my number.

Well done Johnny, which kit are you going for?

 

I think that the 500W is favourite, but given that one might as well be hung for a sheep as a lamb, I might now consider the 750W...

are they all the same motors just with more powerful controllers on them ?

I could be wrong, but is the 750w unit not physically larger than the 500w model, and also 48v not 36v, not that either makes a difference, but just a point.

 

The 500w appeals to me, and of course better battery run time, than the 750w model I would argue.

 

Either way as you say, the gallows await!

are they all the same motors just with more powerful controllers on them ?

 

No mate, the BBS02 48V 500W is just a 750W motor that has been turned down to 18A instead of 25A...we've been playing around with ours and have found that 18A/500W is ideal for where we ride, as we don't want to be propelled over the edge of a cliff when negotiating a tight singletrack:eek:

are they all the same motors just with more powerful controllers on them ?

 

 

Depends who you listen to! Some e bike sites insist that the 500 + 750 are exactly the same motor... I don't have a clue!

Depends who you listen to! Some e bike sites insist that the 500 + 750 are exactly the same motor... I don't have a clue!

 

The BBS01 250/350/500 are all different beasts, but you are right in assuming the BBS02 is the same motor, just programmed differently, albeit badly, from the factory

The BBS01 250/350/500 are all different beasts, but you are right in assuming the BBS02 is the same motor, just programmed differently, albeit badly, from the factory

 

Ahh...programming - that seems to be another hot potato. I think I'll leave that until the damned thing is on the bike and working!

Motor:

•Bafang BBSHD 1000w 48v (1455watts peak)

•Custom controller settings with 100% throttle enabled at PAS-0 and no speed limit (unloaded wheel spinning at 102kmh with 46T)

•46 tooth chainring (74.1km/h top speed on flat)

•189 RPM at 58.8v (factory settings 160 RPM maximum)

•4.8kg motor

- Controller: 30A or 40A? USB programming available

 

Battery:

•Homemade 14s 5p 58.8v 14.5Ah battery pack capacity

•1,5 hours 57.1v fast charge (6A 350w charger set at 57.8v)

•2,5 hours 58.8v charge (6A 350w charger set at 59.2v)

•3.65kg battery pack transported inside my backpack connected to the bike with XT90-S high discharge anti-spark connector.

•70x NCR18650PF Panasonic High Current cells

•Waterproof "bare cells" pack style for better cooling

•No BMS for 100% charge (4.2v per cell) = 100% performance!!

•Range (with BBS02 motor): +/-26km in the city / 36km continuous full throttle with only few stops

Ahh...programming - that seems to be another hot potato. I think I'll leave that until the damned thing is on the bike and working!

 

The standard programming is crap and not user friendly at all, I recommend you use it as supplied for the first few miles to scare yourself on tight sections with big drops, then if you survive, have a look at Karl Geislers blog to see what's possible and change the settings to where you feel right.

Motor:

•Bafang BBSHD 1000w 48v (1455watts peak)

•Custom controller settings with 100% throttle enabled at PAS-0 and no speed limit (unloaded wheel spinning at 102kmh with 46T)

•46 tooth chainring (74.1km/h top speed on flat)

•189 RPM at 58.8v (factory settings 160 RPM maximum)

•4.8kg motor

- Controller: 30A or 40A? USB programming available

 

Battery:

•Homemade 14s 5p 58.8v 14.5Ah battery pack capacity

•1,5 hours 57.1v fast charge (6A 350w charger set at 57.8v)

•2,5 hours 58.8v charge (6A 350w charger set at 59.2v)

•3.65kg battery pack transported inside my backpack connected to the bike with XT90-S high discharge anti-spark connector.

•70x NCR18650PF Panasonic High Current cells

•Waterproof "bare cells" pack style for better cooling

•No BMS for 100% charge (4.2v per cell) = 100% performance!!

•Range (with BBS02 motor): +/-26km in the city / 36km continuous full throttle with only few stops

 

Thanks SW...Some of this I understood - the rest; not so much! Bear with me, I'm a newbie!

Motor:

•Bafang BBSHD 1000w 48v (1455watts peak)

•Custom controller settings with 100% throttle enabled at PAS-0 and no speed limit (unloaded wheel spinning at 102kmh with 46T)

•46 tooth chainring (74.1km/h top speed on flat)

•189 RPM at 58.8v (factory settings 160 RPM maximum)

•4.8kg motor

- Controller: 30A or 40A? USB programming available

 

Battery:

•Homemade 14s 5p 58.8v 14.5Ah battery pack capacity

•1,5 hours 57.1v fast charge (6A 350w charger set at 57.8v)

•2,5 hours 58.8v charge (6A 350w charger set at 59.2v)

•3.65kg battery pack transported inside my backpack connected to the bike with XT90-S high discharge anti-spark connector.

•70x NCR18650PF Panasonic High Current cells

•Waterproof "bare cells" pack style for better cooling

•No BMS for 100% charge (4.2v per cell) = 100% performance!!

•Range (with BBS02 motor): +/-26km in the city / 36km continuous full throttle with only few stops

 

Lol...heavy, back-breaking backpack and crap mileage...not what I'm looking for SW:(

 

On the other hand, the washing machine motored bike we talked about did 86.68mph at Elvo last August at the World Wheelie Event:cool:...but that's about the same speed as the Honda RS250 it was based on lol