Tongxin Specs, are they still current

tongxinpete

Pedelecer
Aug 8, 2011
96
6
Telford, Shrops
Tongxin used to offer motor builds in the following specs, http://www.tongxin.net.cn/en/other.htm
In light of the Chinese ebike domestic max speed going up from 12 to 15.5 mph, are the lower speed motors still offered, if so, they are the only small motors below the now common 201 rpm.
I have the 175 rpm model laced into a 26'' wheel. (13.7 mph top) It is an excellent all round motor set up as I found riding it again lately, makes most hills like pedaling a non powered bike on the flat. The motor dealer recommended it, but I see from the above link that the actual Tongxin spec for my wheel size was 160 rpm!
Maybe if the rider weighs more than my 93 Kg &/or carries a lot of shopping on the bike the 160rpm would be needed. As the torque is quoted a t 20 Nm & on the above chart the speed always remains @ 20 Kph, I am guessing that there was a different reduction gear set fitted proportional to the increasing wheel radius, thus speed & rim pull remained constant no matter what rim was selected.
Jerry, or anyone else here have up to date info re. this? Pete
 
D

Deleted member 4366

Guest
You can make loads of motors run at that speed. You just get a 36v one and run it at 24v, so a 260 rpm Q100H, for instance, will max out at 175 rpm. You can turn up the current to 20A so you get decent torque, which won't slip like the Tongxin. Bafang do 180 rpm versions of their SWX motors, and so do other manufacturers, but it's not easy to get the correct speed from the stockists.

I thought that Tongxin was no more, and that production is now taken over by Outrider?
 

jerrysimon

Esteemed Pedelecer
Aug 27, 2009
3,292
112
Cambridge, UK
I recently purchased three Tongxin motors from Outrider :)

They seemed willing to sell me any preference I wanted. I went for the narrow width 28H, 36V 260RPM models for my folding bike conversions. They had mine on the shelf, but you may have to wait a few weeks if they have to manufacture them for you.

My preference for them is they run silent.

Do you want their email address ?

Jerry
 

tongxinpete

Pedelecer
Aug 8, 2011
96
6
Telford, Shrops
Thanks to both for the good info! A couple of points / questions

d8veh, Re the 260rpm Q100H - 260rpm model, running the 36v @ 24v - 20A
What controller do you recommend for the above?
I have a std Q100 36v - 201 rpm lying around, will try this out - do you know of any motor output graphs for the above motors @ the different rpm builds?
I agree re getting the Bafang SWX at 180 rpm or any other motor at a low gearing is nearly impossible. BMS will never stock anything below 201 rpm.
I am after torque rather than speed - if I could get the Tongxin's torque at a slightly higher speed - well that may be OK providing the cyclist is comfortable assisting the motor & handling the bike at this slightly faster rate, will find out.
The two speed may be the best option long term but I realized it topped out far faster than I personally would ever need on the local cycle tracks, particularly with V brakes on an unsprung bike. I am hoping to build for a friend so am looking at all options

Jerry, Yes please by all means let me have the email address & if possible a link to the official outrider website where you ordered, it was the fact that these motors could be bought in the low rpm (good torque) builds made me consider them again. That is if I am correct in the fact that the rpm change is in the gearing Pete
 
D

Deleted member 4366

Guest
I think I'd be inclined to use the 24v S06S and solder the shunt. I've not yet tried soldering the shunt on one of those, but it worked OK on the S12S, so should be alright. The KU63 can definitely go to 20A but it only has one PAS level (max), which is a bit crappy. I guess the KU65 vis the same, but the start-up is not as smooth as the more modern controllers. There's always a "but"!

The 201 rpm Q100 is fairly well known. It's quite strong up to 12mph and then power tails off a bit to about 18mph. The 260rpm Q100H pulls to about 19mph and then power tails off. The standard Q100 can easily handle 18 amps at 36v, which gives it a lot more punch. I reckon you should try yours with the S06S with shunt soldered for 18 amps. I think that'll probably give you what you want. At 44v and 18A, it comes to life.
 

tongxinpete

Pedelecer
Aug 8, 2011
96
6
Telford, Shrops
Thanks d8veh, have noted all this down, I have a con61 controller already on order from Greenbikekit (was told this is ok for the std Q100) so will try this first. I am assuming the road speeds you mention are in a 26'' wheel.
Which spoke dia & cross pattern do you recommend for the Q100 in a 26'' rim, & more importantly where in the UK would I find the best deal on them.
 

tongxinpete

Pedelecer
Aug 8, 2011
96
6
Telford, Shrops
Having had more time to study all this, I have been looking at the various specs of the small motors on the bmsbatts site.
Q75 max torque 40Nm, reduction 13.4:1, 200W, 36v
is available @ 201 or 328 rpm. (makes no sense to me because if the rpm's change is mechanical, then the torque would change. If done by winding/pole count surely the watts/amps would change)

Q100 std, (torque unspecified) reduction 8.2:1, power 250 / 350 W 36v
speeds 201 or 328 rpm (would point to a winding / pole option as the watts vary, as do the offered speeds)

Q100H (torque unspecified but said to be 30% more than Q100std) 36v
reduction 12.5:1, power 350W, speeds 201 or 260rpm, (again I fail to see if there is only one mech reduction, how the watts remain the same @ different rpm's

I could ask them for a torque spec on the unspecified motors but I fail to understand how it could be the same for both rpm options, pity no max amp draw at either speed option is quoted. Re the Q75, 40Nm @ 201 rpm seems very optimistic for 200W
I will go with what I have lying around but would like to get an insight into these figures
 

tongxinpete

Pedelecer
Aug 8, 2011
96
6
Telford, Shrops
Found this little motor (probably typical) He has good motor curves & data for both 24 & 36V (see both front & rear options for this)
http://www.goldenmotor.com/hubmotors/Mini Rear 36V250W Performance.pdf
http://www.goldenmotor.com/hubmotors/Mini Front 36V200W Performance.pdf
It would appear that in this case at least the 201 rpm @ 5A is up to speed on the flat (max eff), & shows that max torque remains the same at either 24 or 36v, just the speed envelope differs. Also max Amps remain the same in either voltage format. Oh for some graphs & full info! concurs exactly with what you say d8veh.
His smart pie 2 seems a development of his HBM 36 - First motor I bought 10 years ago, & ran in a 20'' front. also selling the faster HBP again I see
 

Geebee

Esteemed Pedelecer
Mar 26, 2010
1,256
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Australia
d8veh, if you limited a Q100H by throttle to the same RPM as at 24v would it be the same torque on 36v (limited by throttle) as if you ran it at 24v assuming the same amps?
 
D

Deleted member 4366

Guest
Yes because the torque at the limit, whether by throttle or otherwise will be zero, but I don't think that's what you mean.

If you have two 36v motors, one with a 36v battery and one with a 24v battery, they won't appear to have the same torque. From a standing start, the one at 36v will get more energy supplied to it, so will have more torque. The throttle only controls the target speed. The controller has its own algorithms to adjust the power to reach that speed. Basically both controllers will give the maximum they can from a standing start. It gets a bit more complicated after that.

If you increase the current of the 24v one to provide the same power as the 36v one, i.e. volts times amps are the same, at take off, power will be approximately the same.

When motors turn, they work like generators. The generated power is in the opposite direction to the power coming from the controller. When the motor approaches its maximum speed, the power generated is significant until at its maximum the voltage generated is the same as the battery voltage, so no current can flow, so no power and no torque. Therefore all motors self-regulate their speed. When you use the throttle to regulate the speed below the motor's maximum, it's the controller that regulates the power flow, but the effect is more or less the same.
 

tongxinpete

Pedelecer
Aug 8, 2011
96
6
Telford, Shrops
If the motor I found http://www.goldenmotor.com/hubmotors/Mini Rear 36V250W Performance.pdf really is a Q100 we can assume two things,
The Q100 (std motor & controller) is 20 Nm, thus the Q100H @ 30% more torque should be about 26 Nm in its std set up.(I would guess 30+ Nm if run as you suggested ie 36v model @ 24v 20A

Reply from goldenmotor told me that the motor is the same one weather used on 24, or 36v. They also say they have an 'open voltage controller' programmable for 24,36 or 48v (cost $35 + shipping) Said to be 25A continuous & 50A peak (unless you can program a lower limit to the current I doubt this would be ideal for the above motor)
I did ask BMS the max torque of the Q100H but the reply was just a link to the existing webpage.
I will try my std Q100 @ 36 & 24v (sadly latter on SLA). may carefully try the shunt mods. see how the torque feels
 
D

Deleted member 4366

Guest
If you run a Q100H at 15A, you can hardly tell the difference from the standard one at 15A. To get the higher torque, I think you have to run a higher current.
 

tongxinpete

Pedelecer
Aug 8, 2011
96
6
Telford, Shrops
Thanks, I did find on the bms Q100H site under downloads, the curve is available http://www.bmsbattery.com/hub-motor/631-250w350w-q-85100sx-motor-e-bike-kit.html
It appears to max out @ 20Nm, same as the goldenmotor, & Tongxin.!

I will try the shunt dodge, & maybe run on 24v, An idea came to me today - to lace into a 24'' rim I have, put that into the 26'' frame, would have to modify the caliper mounting. Pedals would only be 1'' nearer ground, more torque , less speed - (std Q100 as I have one) is there any problem in having a 24'' rear wheel & a 26'' front?
 
D

Deleted member 4366

Guest
I've seen some like that on Endless sphere - I think with 20" rear. If you have a disc caliper mounting point, a disc brake doesn't care what size wheel you have. The motor has the holes for a disc.
 

Geebee

Esteemed Pedelecer
Mar 26, 2010
1,256
227
Australia
Yes, on endless sphere it used to be common to fit a direct drive hub into a 20" wheel on the rear of a 26" wheeled MTB to increase torque, all that I read suggest they road very nicely like that.
 

tongxinpete

Pedelecer
Aug 8, 2011
96
6
Telford, Shrops
I am afraid I have no disc caliper mounting point on any bike I have, so initially I would have to make a mounting for an old school rim brake, & see how the motor performed. Re the other idea of using a 36v Q100 or Q100H @24v to keep torque but at a lower speed, & controllers more generally, would it be possible to do a sticky somewhere of what controllers work with common small motors & a cross reference of the same models overlapping but given a different name by the seller eg con61 / Ku63.?
If I go for running the 36v Q100 @ 24v could I get away with a 20A peak controller ie a 360w in 24v
Where is the best for spokes & nipples?
GeeBee, I have a Golden HBM 36 direct in a 20'' front, (408 clone but a bit more torque) original controller was 400w peak, am told I could go bigger but by how much?