Conversion kit for Dahon Speed/Vitesse

[jhruk]

Thanks for these photos and video jhruk. I have just fitted a Q85 to an old Triumph 20, so recognise all you say about these motors. I bought the motor separately and had it built into a wheel with a new rim sourced from elsewhere. I now think this was probably a waste of my money! When ordering a complete wheel, did you specify an exact rim size (e.g. 451), or did you just ask for a 20" and take whatever they sent?

I think I just said 20” and luckily it was an exact fit – it’s a 406. Seems quite a reasonable quality rim as well - not sure I’d have chosen the radial spoking but no problems so far. I figured that with the whole kit costing only $43 (£27) more than motor alone it was worth a gamble.

Regarding the speed limiter, I connected it up not knowing what it was and thought there was something wrong with the motor! Hopelessly underpowered. When I disconnected it all was well of course. I also had the cruise control connected for a while. This locks the motor on after holding the throttle open for about 8 seconds. You cancel it by flicking the throttle (or, I assume, by applying the ebrakes - but I haven't fitted the switches on mine). I don't really like these cruise controls.

Thanks - I might forget about the cruise control then.

Interesting that you get a waterproof quick-connector with the complete kit - if you buy just the motor you get a long lead that goes all the way back to the controller.

The waterproof connector is very neat but I doesn’t look up to taking any more than the 14 amps the supplied controller draws - if that. I'm hoping it won't melt on a long climb..!

I'm still intrigued by reports that shipments can take weeks to arrive from BMSBattery - the only shipping options I am ever offered take only days, but are very expensive.

Mine was ordered as part of a larger shipment and arrived in about five days - but, yes, shipping was expensive. There were no batteries in the order and it does appear that most delays occur with these.

 

[homemoz]

Having started this thread, I have been following it with interest. I am concerned about the speed of the motor & the difficulty in limiting it to the UK limit. On balance, I have decided against going ahead with purchase & will look at other options. It's a shame as the 83cm width is ideal for small wheeled bikes like the Dahon. The discussion about speed has raised an interesting issue for me about whether anyone has been prosecuted for riding an electric bike over capable of exceeding the legal limit or with a higher max power than 200/250 watts. I suspect my current bike does exceed 15.5 mph although in fairness, I have never bothered checking. May start a new thread to see what info there is out there about prosecutions in the real world.

 

[jhruk]

Having started this thread, I have been following it with interest. I am concerned about the speed of the motor & the difficulty in limiting it to the UK limit. On balance, I have decided against going ahead with purchase & will look at other options. It's a shame as the 83cm width is ideal for small wheeled bikes like the Dahon. The discussion about speed has raised an interesting issue for me about whether anyone has been prosecuted for riding an electric bike over capable of exceeding the legal limit or with a higher max power than 200/250 watts. I suspect my current bike does exceed 15.5 mph although in fairness, I have never bothered checking. May start a new thread to see what info there is out there about prosecutions in the real world.

I may have made changing the controller speed limiter speed sound more complicated than it actually is. Provided you don’t want to reduce the max. speed to below 10mph there is no need to modify the controller at all.

With my extra hour today I’ve just done some trials and found that a 10k resistor wired across the two speed limiter wires will change the limited speed to a very convenient 15.5mph - unloaded. I then took the bike out for a trial run and found it still drew 14 amps maximum, so no real loss of power, and at this speed it felt fine. Maximum motor only speed was around 13mph. I’ve now left this connected but with a switch - my ‘off road button’.

If one was using the pedelec function a speed control may be quite useful. I notice the latest wiring diagram for the KU63 shows connectors for an ‘optional three speed control’ and BMS also do a three speed handlebar control (price $1..!) which they say is suitable for the KU63. My controller didn’t come with these connectors but it would be very easy to devise one with a couple of resistors.

I see they also do a KU63 controller case which, for $3, I may have taken a punt on had it been available at the time.

Bear in mind all my observations are of the 36v version - the 24v may be slightly different.

 

[Deleted member 4366]

If one was using the pedelec function a speed control may be quite useful. I notice the latest wiring diagram for the KU63 shows connectors for an ‘optional three speed control’ and BMS also do a three speed handlebar control (price $1..!) which they say is suitable for the KU63. .

IMHO the 3 speed switch is a waste of time. I've tried it on both their 9FET and 12 FET controllers, so I guess it's the same on the KU63: The speed limit only works on the throttle - not the pedal sensor. You can get the same effect for a lot less effort by not opening the throttle fully.
I often wonder whether the controller software engineers have ever ridden an electric bike!

 

[jhruk]

IMHO the 3 speed switch is a waste of time. I've tried it on both their 9FET and 12 FET controllers, so I guess it's the same on the KU63: The speed limit only works on the throttle - not the pedal sensor. You can get the same effect for a lot less effort by not opening the throttle fully.
I often wonder whether the controller software engineers have ever ridden an electric bike!

Thanks - I agree that does sound rather daft. I haven’t fitted the pedal sensor on mine so it was just my assumption that the speed control would work on that as well. As you say no real point in a speed limit on the throttle - unless you wanted to keep the assisted speed strictly within the regulations.

 

[kouchris]

This is a dream thread for me as I have had on my mind the conversion of my dahon D7 vitesse for quite a long time..I have started a thread of my own about it a while ago but I have lost hope in it as the prices were quite high and I didn't think I could afford it at that time.

I’ve fitted the 36v version of this kit to a 20" Dahon Impulse & so far I’m very impressed with it - see my previous post.

The 24v version is likely to be rather less powerful as I believe both the controllers are set to limit the current to about 14amps. Given the gauge of the supplied wiring I’d be wary of increasing this.

They appear to offer this motor in two widths for forks of 83mm or 100mm. If you’re going to fit it to a 20” Dahon you’ll probably need the 83mm width - but check first. The link d8veh gave was for the 100mm version - the 83mm is here.

Jhruk you suggested the 83mm version (nice input for the careless people like me). At the bmsbattery Q85 36V Front Driving V-Brake E-bike Kit site there is a tab under DATA Sheet that says “cable location Left”. Does that mean that the cable comes from the left side of the motor (the same side that the folder Magnet is?)
I took some pictures of my Dahon D7 and as you can see the space there is really tight.. Was that an issue?
I see in you photos that is the case. But is seems like your folded steering wheel goes further down than mine does(?).
Photos:






Another thing that concerns me is the waterproof ability of the bike.. Hows that going for yours?
I really admire the work you ve done with your impulse. Seems really neat, what I hope to achieve. How much does it weight and hows the mobility?

 

[shemozzle999]

Hi d8veh,

Re: #3 post

Just a couple of quick questions on the Q85 motor kit.
1. Is the connector supplied at the motor end a moulded on variety or can it be un-assembled?
2. Has BMSBattery given you combined shipping charges on your previous multiple purchases?

Regards, shemozzle999

 

[jerrysimon]

I have seen those molded connectors. If they are like the ones they now do on the Tongxins then the good thing about them is that their diameter is small enough that you can remove the washers and nuts over them to add more spacer washers if need be!

Regards

Jerry

 

[catsnapper]

I've a small batch of the Q85 hubs for 20" wheels arriving in the next couple of weeks. One is currently unsold, so if anyone might be interested in having it let me know. I'll then contact you when they arrive and see if you still want it.
As a wheelbuilding business I can supply a finished wheel with a decent rim and Sapim or DT Swiss spokes.

The hub comes with a suitable mini-controller for use with or without hall sensors.


Alan

 

[catsnapper]

I should have added these are the 36V version of the Q85 The controller is optional if not required.

Alan

 

[shemozzle999]

Hi Jerry,
That is one of the reasons I needed to know the answer.
It would be nice to retro-fit them on my Brompton - I had to do a puncture repair the other day it was a bit of a fiddle, I did not want to pull on the motor cable and do some damage.
If it is suitable, my next problem would be to talk BMSBattery into supplying me one or 2.
Regards, Colin.

 

[Deleted member 4366]

The connector's about a foot from the motor. If you need the exact length, let me know and I'll measure mine.

 

[shemozzle999]

Any chance of a close up photo of the connector ie: pin configuration when un-mated overall diameter and whether it is moulded?
Thanks, Colin

 

[Deleted member 4366]

Any chance of a close up photo of the connector ie: pin configuration when un-mated overall diameter and whether it is moulded?
Thanks, Colin

Motor side (male inner) 10mm
Controller side (female outer) 14mm

 

[jerrysimon]

Yep thats the one. Kind of you to post the photo. I have one of those connectors on a new Tongxin I have. Neat and as I say fits through the rubber guard, washers and nut if you need to add additional washers.

They are molded however so you cannot take them apart.

Regards

Jerry

 

[shemozzle999]

Ditto Jerry's thanks d8veh they answer all my questions.
Regards, Colin.

 

[jhruk]

This is a dream thread for me as I have had on my mind the conversion of my dahon D7 vitesse for quite a long time..I have started a thread of my own about it a while ago but I have lost hope in it as the prices were quite high and I didn't think I could afford it at that time.



Jhruk you suggested the 83mm version (nice input for the careless people like me). At the bmsbattery Q85 36V Front Driving V-Brake E-bike Kit site there is a tab under DATA Sheet that says “cable location Left”. Does that mean that the cable comes from the left side of the motor (the same side that the folder Magnet is?)
I took some pictures of my Dahon D7 and as you can see the space there is really tight.. Was that an issue?

The cable does exit the motor on the left. It doesn’t affect the folding on mine & seems preferable as it protects the cable from damage when folded. See photo:

I see in you photos that is the case. But is seems like your folded steering wheel goes further down than mine does(?).
Photos:

My Impulse has a quick release adjustable telescopic handlepost & I adjust this before folding. I’ve marked the positions on the post with an indelible pen. Looks like your D7 is adjustable as well.?

Another thing that concerns me is the waterproof ability of the bike.. Hows that going for yours?

As I only use the bike for leisure I try to avoid wet weather & therefore didn’t worry too much about waterproofing. It’s really down to how you install it. The motor should be the same as any other – some people put a squirt of silicone sealant into the axle where the wires come out. The ‘waterproof’ motor cable connector at least looks as if it might live up to its claim. The rest would be trying to keep the connectors to the controller as dry as possible & maybe enclosing the controller.

I really admire the work you ve done with your impulse. Seems really neat, what I hope to achieve.

Thank you – it was really easy with the kit & only took an afternoon. Just make sure you’ve got plenty of cable ties handy!

How much does it weight and hows the mobility?

I haven’t weighed the bike but the claimed weight for the motor is 1.9kg and allowing 0.5kg for the controller, wiring etc would suggest it adds around 2.4kg to your existing bike – excluding your chosen battery of course. At present I use mine with a fairly heavy 15Ah Ping battery, which I switch between other bikes, and I now use an Altura rack bag to contain it. This comes with a ‘landing strip’ which is permanently attached to the rack & allows for quick & easy removal of the bag - which then becomes a shoulder bag. This makes the bike much easier to handle if you have to carry it far or put it in the boot of a car - it’s also claimed to be waterproof!

So far no real problems & I’m still very happy with it.

 

[jhruk]

Motor side (male inner) 10mm
Controller side (female outer) 14mm

Interesting…. You must have the ‘Sensorless compatible plug’ with only the three pins. I have the hall sensor version which packs nine pins into a similarly sized connector. Even the larger pins look a lot smaller than on your three pin version – hence my concern about its use with higher amperage. I wonder if the wiring is of different gauge as well ?

 

[kouchris]

My Impulse has a quick release adjustable telescopic handle-post & I adjust this before folding. I’ve marked the positions on the post with an indelible pen. Looks like your D7 is adjustable as well.?

Great.. I haven't thought of that. Good pointer. I adjusted that just like yours and it is out of the way.

As I only use the bike for leisure I try to avoid wet weather & therefore didn’t worry too much about waterproofing. It’s really down to how you install it. The motor should be the same as any other – some people put a squirt of silicone sealant into the axle where the wires come out. The ‘waterproof’ motor cable connector at least looks as if it might live up to its claim. The rest would be trying to keep the connectors to the controller as dry as possible & maybe enclosing the controller.

The controller seems to be the biggest issue.. The wiring job should be challenging. Cable ties MOST HANDY INVENTION

I was considering buying a seat post with suspension.. Hows yours treating you? Back-pain? i believe when speeding a bump is going to be dangerous, balance-wise and shock-wise. (?)

Thanks a lot for you input on this thread. Really appreciate it.Hope i can upload some conversion of mine soon.

 

[jerrysimon]

Wow that one would make an excellent unbilical plug for my Brompton. Smaller and an extra pin compared to my Bulgin!

I need to get me some of those!

PS Current would not be an issue on a Tongxin. Remember the load is split across the three pins. My Bulgin is rated to 6-8amps per pin I think. The pins on that look thicker!

I assume its keyed so it can only plug in, in one orentation ?

Regards

Jerry