Brompton M2L-X (Titanium) - Super Lightweight Pedelec Conversion

[cwah]

Thanks Jerry

Have you thought of the hidden brake sensor?
HWBS - Hidden Wire Brake Sensor 1pcs - BMSBATTERY

It's probably less DIY and a bit more bulky but much simpler and able to fit to any brake?

 

[jerrysimon]

Have you thought of the hidden brake sensor?

I am pretty sure they won't fit on the Brompton brake arrangement.

Regards

Jerry

 

[jerrysimon]

Did my first comute in today. I have a new app on my android phone (Strava).

Its a cross Cambridge city commute so quite a few stops and starts plus I stopped at the cash machine.

5.1 miles, 76' elevation gain, 25 mins, average 11.9mph.

It was a little bit windy and I was lazy so used assistance quite a bit. Had the Turnigy wired up and it read 0.975mAh used when I got to work.

Regards

Jerry

 

[cwah]

Thanks Jerry. I was thinking about buying it but it's probably better to have something compatible with my bike.

 

[John in DC]

However my new 2011 ones look more promising. Shown here next to the micro switch/cable. The brake fixing for the handle bar is different and leaves room for the micro switch to be fitted.

First cut out the existing hole where the setting grub screw was. You have to open it out to around 12mm and take away some inside material.

Excellent work(as usual), Jerry -

Question: Is the micro switch you used above of the NO (normally open) or NC (normally closed) variety?

Rgds...

- J

 

[jerrysimon]

Question: Is the micro switch you used above of the NO (normally open) or NC (normally closed) variety?

NO - normally open as shorting the wire (operating the brake) closes the circuit and turns off the motor. The switch is taken out of one of the standard cutout brakes that comes with most of the chinese ebike kits.

Regards

Jerry

 

[benjy_a]

NO - normally open as shorting the wire (operating the brake) closes the circuit and turns off the motor. The switch is taken out of one of the standard cutout brakes that comes with most of the chinese ebike kits.

Regards

Jerry

Jerry,

Operating the brake releases the switch thus closing the circuit- normally closed I think? When not braking the switch is depressed (not in it's intended normal position).

Ben

 

[John in DC]

The other end of the Bulgin plug in its parked position on the carrier block, which has a modified female Bulgin socket attached to it.

Another question, Jerry -

Does the native connector that came on the hub motor connect directly to the native connector that came on the controller?

If not, can you recommend a source for matching connector for the hub motor?

Thanks...

- John

 

[jerrysimon]

John,

Yes it does. The controller and motor are exactly matched and come as a set. I tried another controller with the motor and although it ran, it was no where near as smooth as with its supplied controller.

Of course if you are going to mount the controller in the bag and fit the umbilical chord, then you will need to cut and shorten all controller wires anyway and extend the one to the pedelec sensor which will be too short. Also I found that until I took the small plug they supply to plug in the sensor out of the circuit, I got inconsistent results using my bulgin plug.

Regards

Jerry

 

[polyphasic]

Jerry, I recall you stating in the previous thread that spreading this titanium fork was more difficult than the steel forks, because the Ti tends to want to springs back. Obviously, you were able to do it. I have two questions.

First, I'm wondering say a manufacturer comes out with a product that is better than the Goldant and doesn't require spreading the fork, i.e. it fits a standard Brompton fork. Would you be able to fit that motor on this same Ti fork? In other words, could you downsize it back to fit say a regular wheel or is it permanent?

Second, Would you mind sharing some tips on how to spread a titanium fork for this Goldant?

 

[polyphasic]

Another question I have is can you spread the Ti fork while it's mounted on the bike frame or do you have to take the fork off the bike before you spread the fork?

 

[jerrysimon]

I did mine when installed on the bike. The harder part is to file out the Ti fork dropouts to accept the 10mm motor shaft flats. My dremel did the job in the end but ate up a couple of bits in the process.

Spreading can be done with the usual threaded shaft with nuts and washers on both ends or like I did with a block of wood slowly pushed down into the fork spacing gap. I will post some pics later. As I said the Ti has a high tendency to spring back and you have to be quite brutal with them!

I would add no guarantee can be given that this will not damage the Ti forks. I have taken the risk and will report back if I have any subsequent failures.

Ps and to add yes I think you could refit the original wheel/a new slimmer motor into the forks again, though I don't think you would want to keep widening and closing the forks too many times as the fatigue might eventually lead to failure.

Regards

Jerry

 

[piotrmacheta]

Jerry, I'm so impressed with this that I'm going to get a kit and then worry about the bike later. Just in case you didn't know, during my enquiries I was told that I can get a throttle with the external controller (but not the built in controller) but the pedal sensor is also required so not sure quite how this will work.
I have a mad idea to fit it onto one of these!

 

[jerrysimon]

Well my motor is fitted and I have used it for about a week or so on my daily 10 mile round commute. I really want to test it thoroughly for six months or so before I recommend it. Some of the early Tongxin Nanos had problems though more with their controllers.

By all accounts so far its been ok albeit that the pedal sensor wire is sensative and perhaps not best to cut or lengthen the stock controller wires. At least we now know how the pedelec sensor should be fitted.

Would be interested to hear about the throttle option as when I asked they said there was no option.

Whilst the pedelec option is ok, I am still having a bit of a struggle getting use to no throttle option.

I actually find though that I am moving faster with this motor that seems to top out at about 16mph over the 14.5mph of the Nano, even though both are speced at 260RPM ?

A scooter option looks interesting but no pedals if you have to fit a pedelec ?

Regards

Jerry

 

[piotrmacheta]

I was thinking of mounting the pedelec sensor magnets onto one of the wheels so that as you push off then it senses movement of the wheel as if it were the pedals and gives power and then hopefully control on the throttle with brake cut-off switch to stop it if it all got a bit much. A bit different to the usual and looks like it might be fun. Not sure about the leglities of all this as without pedals it might not be allowed - ASBO?

 

[Scimitar]

I have a mad idea to fit it onto one of these!


View attachment 3756

You can do - first contact I had with a modern electric bike was via a forum where one of the members in Finland did exactly that with a 1000W 48V motor for his commute. Legality went out of the window, even in Finland, I suspect.

 

[jerrysimon]

I was told that I can get a throttle with the external controller (but not the built in controller) but the pedal sensor is also required so not sure quite how this will work.

I have spoken with Sky who has confirmed a new controller which has the throttle option has been designed and will be available. Sky said that the pedelec is required because these are non hall motors but I don't see why the throttle option could not be fitted on its own. I guess the reference was because non hall motors don't really start up as well as ones fitted with halls and its better for them to be moving first.

I asked about the existing Tongxin Nano controllers and Sky confirmed that these run a little rough with the Goldant motors, which ties in with my experienced when I tried one.

Regards

Jerry

 

[daniel.weck]

I would add no guarantee can be given that this will not damage the Ti forks. I have taken the risk and will report back if I have any subsequent failures.
...
Ps and to add yes I think you could refit the original wheel/a new slimmer motor into the forks again, though I don't think you would want to keep widening and closing the forks too many times as the fatigue might eventually lead to failure.

I have been carefully monitoring the "health" of the front wheel assembly on my Brompton since I widened the (steel) fork, because a failure at speed would likely result in major injuries, especially in busy traffic. There are substantial gradients around my neck of the woods, so unassisted downhill top speeds are quite "interesting" because the Brompton's small wheels and low gearing.

For my "dual" hub motor setup (see signature), I simply pad the empty axle space with thick washers when I use the Tongxin instead of the 8-Fun kit. I other words, I widened my forks once and for all, so that the widest motor fits in. In practice, I use the Tongxin kit more, but I know I can easily swap at any time (e.g. in the event that the weaker Tongxin design fails, given the rather intense uphill usage)

Cheers, Dan

 

[polyphasic]

Jerry, Would you mind posting those pictures when you get a chance? I'll probably be getting the motor in a week or so. Currently, I hate hills, love the flats and love love downhills.

Spreading can be done with the usual threaded shaft with nuts and washers on both ends or like I did with a block of wood slowly pushed down into the fork spacing gap. I will post some pics later. As I said the Ti has a high tendency to spring back and you have to be quite brutal with them!

That would be a cool ride. I have a custom human powered kick scooter with 8" tube tires for the nearby gym. It's something I can leave unlocked in the gym office without much worry of theft. It would be interesting to know how far this scooter would go on pure throttle using the Goldant. I just sent Sky an email asking about the throttle availability time frame.

I have a mad idea to fit it onto one of these!


View attachment 3756

 

[dingrpdl]

Polyphasic,

I spread my Brompton fork using a threaded shaft and nuts. When spreading using this method, you have to be careful that the whole threaded rod assembly does not spring out of the dropouts during the spreading operation. Otherwise it will be ejected with great force. I used the original dropout retaining washers to prevent this from happening. You can see these (in the picture below) on the inside faces of the fork securely hooked into the holes in the fork.

Richard