Tongxin Motors - Higher RPM

[jerrysimon]

I never realised that you could now get the original narrow 80mm wide Tongxin "nano" motors in the higher RPM, i.e. I thought the max was 260RPM

After correspondense with Anna at Outrider I just received two 36v, 28H, 290RPM motors to try. Although mostly I use the smaller Keyde motors in my light conversions, in the winter it is nice to have a little more torque.

My calculations give me at least 16mph on these in a Brompton rim being powered on a full charge of 42V

I must admit things have come a long way from four years ago when I first began exchanging numerous poor/broken english emails with a complete stranger in China, waiting for six to eight weeks for them to be made and ending up with some roller brake version or something you never expected finally in the post. Also back then 36H flanges were the norm which had to be laced into my less favourite hard to source, expensive 16", CR18 rims that hated tires being fitted or removed from them. Now communication is clear, easy and they send pictures of what you are getting with your final quote. These took less than a week to make (in fact they started making them before I placed my order) and were delivered in just a few days. They also now include literature of their other stock with tempting pictures and diagrams of other kits you can buy.

I am looking forward to trying one of these babies out on my original steel Brompton replacing the original now rattley Tongxin motor that has 6000 miles on it and has always found it hard to push me and the bike along at anything more than 13mph without pedaling.

Regards

Jerry

 

[Deleted member 4366]

Why don't you add extra cells into your battery pack? As you don't use a BMS, you don't have any constraints on the number of cells. It'll only take a couple of minutes to do, and you get an instant 10% increase in speed and torque for each additional cell with your present motor. Your controller should stand two extra cells for a 20% gain - maybe three. The only thing you lose is the LVC, but you can soon wire up a voltmeter if you don't already have one. You'll get proportionally more range too.

 

[jerrysimon]

Fair point Dave and I agree would work.

Of course I would then need to change my simple cheap bulk charging solution. Also as I use two 5s2p or 6s1p Konian or A123 packs this would require at least 2 or 4 cells to be added.

Also as you know I have an obsession with keeping weight down on my light weight conversions


Regards

Jerry

 

[Deleted member 4366]

The aluminium chargers are usually adjustable - if that helps.

 

[jerrysimon]

Well finally built my new Tongxin 290RPM into a Brompton rim. I had hoped to use one of the new double walled rims I purchased for the Brompton but got the spoke length wrong for radial

Anyway fortuately they were the right length for an original Brompton 28 hole single walled rim so here it is laced up radially.

Here is the oringinal 36v, 260RPM, 36H Tongxin motor some 4 years and 5000 miles later. Still working but pretty rattley when you spin it lol.

Finally how it looks on my trusty Bromotn M3L the bike where it all began for me looking for a lightweight portable electric bike.

Although heavier than my Titanium Brompton M2L its nicer to have a little bit more power in the winter with this larger Tongxin over the Keyde motor.

On the original motors we use to have to mess around finding larger three pin connectors (shown on the original motor above) whereas now the attached three pin waterproof connectors are neat and small enough to slide through the nuts, washers and Brompton mudguard stay/frame clip.

Things have moved along nicely for DIY conversions compared to a few years ago. All very nostalgic really lol

Took it out for a spin and the higher RPM gives me assistance under load of around 14.5-15mph compared to 13-13.5mph of previous lower RPM motor.

Regards

Jerry

 

[Joneser]

Are the Tongxin kits more plug and play than other options?

Out of Tongxin, Cute, 8fun and Keyde what is easiest for the layman?

 

[jerrysimon]

Well I would say the Keyde are least plug and play if you want to change them to throttle option. All the Tongxins I have used have been sensorless so only three wires and I think are pretty easy to set up. Then again, I suspect Cute/Q and 8fun motors are not that hard to set up as many use them in DIY builds.

For a simpler plug and play for the Brompton IMO the narrower 80mm wide Tongxin are probably the best fit, though some like more power which usually means larger/heavier motors and stretching the forks to 100mm which makes the fold more problematic/wider.

Jerry

 

[patpatbut]

Well I would say the Keyde are least plug and play if you want to change them to throttle option. All the Tongxins I have used have been sensorless so only three wires and I think are pretty easy to set up. Then again, I suspect Cute/Q and 8fun motors are not that hard to set up as many use them in DIY builds.

For a simpler plug and play for the Brompton IMO the narrower 80mm wide Tongxin are probably the best fit, though some like more power which usually means larger/heavier motors and stretching the forks to 100mm which makes the fold more problematic/wider.

Jerry

Hi Jerry,

Good to know there is a high speed version of Tongxin. Just wondering would they be able to make a little higher RPM motor like 328rpm?

Do you think for that speed it will overheat the motor?

Pat

 

[jerrysimon]

I don't know if they could take the motor up to 328RPM. As far as I know its the current that dictates the heat generated or power limit V x I so providing they are kept within the power spec limits (around 400- 450 watts) it should be ok.

As Dave said if you want faster assistance maybe the answer is to use a cell or two more in series but as stated you would need to limit the current to keep the power down.

Regards

Jerry.

 

[patpatbut]

I don't know if they could take the motor up to 328RPM. As far as I know its the current that dictates the heat generated or power limit V x I so providing they are kept within the power spec limits (around 400- 450 watts) it should be ok.

As Dave said if you want faster assistance maybe the answer is to use a cell or two more in series but as stated you would need to limit the current to keep the power down.

Regards

Jerry.

Thanks Jerry.

Do you notice any different in term of the noise of the motor?

Pat

 

[jerrysimon]

Tongxin is virtually silent from the go. Keyde was a little louder when I first had it but still quite quiet and now after a few months as silent as the Tongxin.

From what I have heard all the other motors (except direct drive I am told) are not quiet and can clearly be heard when engaged. That was another reason why I first tried a Tongxin, though these days I would be less bothered about others hearing my motor. I am proud to ride an ebike every day to work now, even if others who may ride their stock bikes to work a few times a year tell me I am cheating

They of course are using their cars

Jerry