The Tongxin Motor thread

[HTB_Terry]

John,

The repair charge is $50 USD plus shipping. Locals can bring the bike or wheel by the shop. Obviously, for shipping the unmounted motor is best, but you can send the wheel. Our mailing address is on the website (Commerce Blvd). I assume Tongxin improved the ring as they were aware of the issue, but I don't have the details on the improvements. Stressing the motor would be a 200 pound guy going up a hill. 36 V at 10 amps is no problem. The controllers are rated at 15A. A comfortable load for this motor would draw 8-10 amps cruising on level ground.

Terry

[Timbo]

Timbo,
That BF motor is really good! I have mine running at 36V, and it pulls really well. Have been 42 kph mounted in a 20" wheel. Had same motor in a 26" wheel, and it topped out closer to 50 kph, but with less torque.
It a bit heavier than the Tongxin though, at about 3 kg.
Dunno what my range is, haven't drained the battery yet, but have gotten 35 k and battery still feels strong, so I reckon I should get 40?

What controller are you using? With the BF I'm getting extrodinary range - more than 50km - but my speed tops out at 26km/hr. I miss the wind in my face.

[Timbo]

John,

The repair charge is $50 USD plus shipping. Locals can bring the bike or wheel by the shop. Obviously, for shipping the unmounted motor is best, but you can send the wheel. Our mailing address is on the website (Commerce Blvd). I assume Tongxin improved the ring as they were aware of the issue, but I don't have the details on the improvements. Stressing the motor would be a 200 pound guy going up a hill. 36 V at 10 amps is no problem. The controllers are rated at 15A. A comfortable load for this motor would draw 8-10 amps cruising on level ground.

I think 'level ground' is a significant point. Although my commute was always on the road or sealed bike paths, potholes and uneven blacktop were an ongoing concern on rigid forks - sometimes they can't be avoided and I reckon that this stressed the first motor until it finally gave up - and the same thing was happening to the second. I weigh less than 60kg & used the thottle sparingly when setting off.

[Johnbear]

There are alot of hills here, a big reason I like my motor! But the tongxin cannot cut it. As much as I enjoyed the 4 times the motor worked, the 4 break downs sucked, riding 15km home with batteries was a bit heavy, but I made it. The tongxin may have a total of 150kms on it. My luyuan direct drive brushless motor has over 5000kms. My crystalyte over 1000km, various other direct drive motors roughly another 3000km. No problems with any of the motors except the tongxin.

[docnjoj]

I and my trike weigh> 300 lbs, so it is not surprising that the Tongxin failed! The Bafang has been excellent, but would not work well with Xlyte analog 20 amp controller! With Infineon it is wonderful!
otherDoc

[Johnbear]

The bafang is very tempting, I may buy one, I want at least on lightweight bike! Is it quiet?

[docnjoj]

Very quiet and I am a lunatic for quiet! At speed (> 8 mph ) u cant hear the gears. + 1 for Nylon!
otherDoc

[HTB_Terry]

The symptom for the cracked ring on the Tongxin is that you will hear the motor spinning, but the wheel doesn't turn. If you lift the wheel, it might turn slowly. No reason to junk the motor when it can be repaired. All readers of this forum will receive a 20% discount on the repair, so the cost is $40. If you have already opted for a bigger motor and want to sell the broken Tongxin, contact me.

One other thing to watch for is that the axle can bind on one side. If the nut gets loose on one side, the axle can spin. As someone mentioned, this motor has a split axle, the left and right sides are two different pieces so if one side turns and the other doesn't, the motor will jam. So if the motor quits, first loosen then tighten both nuts.

[The Stig]

Is there any chance things have changed now that 6 months have gone by. Any design changes? Anyone who has run the tongxin at 48v? 20A?

[The Stig]

Bump

[frank9755]

Not heard of anyone overvolting but in the last year Tongxin controllers seem to have become far more reliable. Many have been sold on Cytronex bikes and as kits with no reported failures. My latest one is going strong, without wishing to tempt fate.

[vendybiker]

Is there any chance things have changed now that 6 months have gone by. Any design changes? Anyone who has run the tongxin at 48v? 20A?

I have one 24V Tongxin and I use it on 48V/17A controller. It´s realy fast and powerful. As far as good (I have it about 1 year).

[Timbo]

Is there any chance things have changed now that 6 months have gone by. Any design changes? Anyone who has run the tongxin at 48v? 20A?

I have one 24V Tongxin and I use it on 48V/17A controller. It´s realy fast and powerful. As far as good (I have it about 1 year).

48V? What speed are you getting out of it? On my second 36V motor I could do 41km/h.

[Pete1961]

I bought a Tongxin (175 rpm , spoked it into a 26'' ATB wheel) early 2006, & have run trouble free ever since, using the bike at least twice a week. Its long life I put down to always pedalling first from standing, not overvolting & I have the controller pinned down to the steel trunking SLA batt case (thus giving it a big heatsink & cooling in the airstream when riding). I found out since that Tongxin reccomend 160 rpm rather than 175 for my 26'' wheelsize, giving an extra 10% of torque than I am using. Admittedly this would mean 12.5 mph top speed, rather than my 13.7 max assisted. Unless in very flat country I would not go to the 190 rpm version favored by Tony Castles, or indeed beyond that. (could be that Tongxin make these reccomendatios to comply with Chinese ebike speed law of 20 kmh / 12.5 mph) but by following this the drive system is less stressed I think. Anyway it's a great little 1;1 hill assist & light too.

I have been asked to help a friend get something similar together, Tongxin will sell me a one off in whatever rpm I wish BUT they now push a 'no halls' or sensorless model saying its more reliable. I can see how this could work on an xlyte DD but not on one of these as the motor is not turned by the bike moving UNLESS they have dropped the frewheel aspect (something I like) Was wondering a) how this works in theory as no back emf's to sense, & b) DOES it really work in day to day use on one of these motors, ie has anyone direct experence of this new tech.

Tongxin are the only people doing a sub 200 rpm motor (bms battery used to but do not now & as far as I am told will not re stock this option - pity as bms have been ok to deal with in past (am expecting some pouch cells from them soon, as trying a ypedal style batt build !!!) The bms 204 rpm motors would do me fine in a 20'' but he does'nt want this. Pity i live in such a hilly reigon, Pete

[Erikjan]

My motor makes the strangest sound do somebody know what the problem is?

http://www.youtube.com/watch?v=YGpsHkSedi4

After a while the sound disappear and the motor works normal for a few km.

But after a few km it makes that other weird sound I think it is really damaged now.

http://www.youtube.com/watch?v=SNge8EQALoE

The controller is a sensorless lyen 6fet.
Motor 36V 190rpm tongxin.

[Erikjan]

^^
I know the problem,i opend the hub and find a magnet come of.

some pictures:
https://picasaweb.google.com/1127516452 ... Tongxinhub

I call the shop how sell me the hub and i have still waranty after 1,5 year i am happy now.
Send the hub back now i have te wait for the new one.

[The Stig]

Is the tongxin an inrunner?

[amberwolf]

yes, if it is like mine:
http://endless-sphere.com/forums/viewto ... =2&t=25188
viewtopic.php?f=2&t=33246

[The Stig]

How do you like it as a small gear motor amber? efficient and robust?

[amberwolf]

Haven't finished the bike to test it yet. But it will be a middrive not a hub, so it should help the survival of things like the outer ring. No shock loads on it; no axles to bend, etc.

[Erikjan]

Because you cannot hear the motor running, they are very silent.
But they are not verry strong. I broke 2 in 4000km.
The first had a broken ring. The second a magnet come off.

[The Stig]

How much power were you running them at when you broke 2 in 4000km? Sounds like its more suited for mid-drive....

[Erikjan]

First one last 3995 km @ 400W max 28 - 30 km/h
i have 28" bike.

Second last for only 5km then magenet come off.
Factory fault i think.

[amigafan2003]

FYI I'm now running my Tongxin @ 63v (15s lipo) and I've set a 12a limit in the controller which see a peak wattage of 725 on my Turnigy meter.

The bike cruises @ 25mph and on my 18.5mile round trip commute I'm using 7Ah from my 10Ah pack averaging 21.5wh/mile.

Hub has just passed the 800 mile mark.

I'm very careful with the hub - I never use it from a standstill and I'm gentle on the throttle to ensure I don't induce clucth slip - which I believe to be the primary cause of the ring breaking in Tongxins. I don't have any hills where I live (coastal resort in the UK) and 7 miles of my 9.2mile one way commute is solid cycle path with no traffic control (so no stopping and starting) and only two junctions after that. This no doubt is helping prolong the life of this motor.

We'll see how much longer it lasts at those power levels

[docnjoj]

Is there any place that these motors (Tongxin) can be purchased in the US?
Thanks in advance.
otherDoc