Tongxin freewheel problems ?

[jerrysimon]

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** NOTE ** This thread has been updated and a better way of taking the motor apart is shown here also with better pictures.

The thread below details what happened when I intially had problems with the freewheel.

***

Well things have been going so well, so a little disappointing that I seem to now be having problems with the freewheel.

Basically I have done about 400 miles with no problems. Today I brought my bike to my brother in laws in Canterbury to go out for a cycle.

At the beginning of the ride, I noticed the front wheel started making rather a lot more noise when the motor was not engaged. As soon as I apply power its alomost silent as is normal for Tongxin motors.

Once I get up to 15mph where assistance stops then the noise comes back as it does when I cut power.

The best way to describe the noise is like a ratchet sound that you get when you use one of the wrenches with a ratchet, kind of a clicky/springy sound. It did stop for a little while then came back. If you turn the wheel backwards or apply power its silent.

Operational wise everything works perfectly except for the rather loud/annoying/embarassing ratchet sound. Even when I apply a tiny bit of power the noise emediately stops.

So is it a failed/failing freewheel ? I have a second motor that I ordered so it not all bad news. Will the freewheel suddenly fail and the wheel lock up ?

My biggest worry

Suggestions/comments ?

In the meantime I am about to build my second wheel anyway.

Regards

Jerry

 

[HarryB]

Sounds like a freewheel problem but could go on for some miles before failing completely. I have had freeweels fail but they have all gone different ways but I have never heard of them locking up as this seems very unlikely. One did make a racket but never actually failed. One was a little noisy particularly after the cutout speed but failed electrically so I am not sure if the noise was relevant. The last time it failed it did it utterly silently! Hope this helps.

 

[jerrysimon]

Harry much appreciated response.

My main worry is that it would suddenly lock up. On the cycle back it actually stopped making a noise, but we then stopped to visit some people for a cup of tea and when I got back on it started again.

I will continue to ride and see what happens. I am expecting some more spokes in the post next week, so can build up my second wheel then.

It may in fact have been my fault, as when I first got the motor I initially tried to take it apart without knowing much about it. As per my build post I was concerned I would have to cut one side of the long shaft down that had the roller brake fitting on it. I decided to leave it as is, but may have weakened or damaged it in trying to initially take the side plate off

Anyway we will see and as I said I have a spare one which I have not messed with at all

PS I have since seen on the German pedelec forum how to take them apart are the freewheels repairable ?

Regards

Jerry

 

[HarryB]

Yes all repairable but the difficulty is findiing the parts if the freewheel has broken. It may just be a broken spring or the ring that holds the freewheel together that can break but you will have to open it to find out - and sometimes that is the challenge. If you can find a source of motors they are reasonably cheap that may be a better solution. If you do manage to get it apart some pictures would be interesting. Mark at cytronex may be able to provide parts if you give him a ring but I am doubtful about that.

 

[jerrysimon]

Thanks Harry,

I will get the new one up and running first.

There are some pics on the german pedelec of them disassembled and how to do it.

I will search out the links later and post them.

Regards

Jerry

 

[Geebee]

Thanks Harry,

I will get the new one up and running first.

There are some pics on the german pedelec or them disassembled and how to do it.

I will search out the links later and post them.

Regards

Jerry

This may be worth checking as a slight misalignment maybe the noise?
This is a quote from Endless-sphere.com • View topic - The Tongxin Motor thread

"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."

 

[jerrysimon]

Thanks for the link GeeBee,

I am pretty sure it is not that, as I have already loosened and retightened nuts on both sides. Also reading that other post it seems its not the metal ring either.

Anyway once the new motor is on I will take the old one apart.

Regards

Jerry

 

[jerrysimon]

I found the link showing the Tongxin disassembly

eBike mit Tongxin als Kettenantrieb - Seite 36 - Pedelec-Forum

Dan had posted it in my Tongxin wheel build.

Regards

Jerry

 

[daniel.weck]

Good luck with the troubleshooting

++Dan

 

[wurly]

Jerry, does it feel like you are turning the motor when pedalling. That would be a sure sign of something jamming the freewheel. I have taken these things apart and have noticed that the freewheel assembly is very weak around the springs and bearings. Maybe there is a fragment of metal or ones of the springs has broken free.
I have drawn lines to show you where they break.
Mel

 

[jerrysimon]

mkc1

I have taken the wheel off the bike just to make sure nothing is compressing the shaft and its all free.

I have done a video of the problem to show whats happening.

Basically everything is working fine the wheel spins by hand and eventually stops, the motor works fine and it will tunr backwards. Then the motor is applied or it is spun backwards no sound at all. When its spun in the direction of travel it make a clicking noise just like a rachette.

I would be interested to know how you got it apart ?

Ps looking at your picture maybe one of the springs has come loose and is rubbing or something.

Regards

Jerry

 

[jerrysimon]

Ok here is the Youtube video showing the problem. As you can see the freewheel seems to work fine it just make a racket when the freewheel works but silent when its running under power ?


Youtube Video

Regards

Jerry

 

[HarryB]

Sounds bad - a lot worse than any of the noises I have ever heard from my cytronex. Good luck with getting it apart.

 

[wurly]

I see what you mean. It seems like the wheel stops spinning quicker than mine although that maybe down to the smaller sized wheel. It isn't difficult to take apart, as long as the cover unscrews ok. First remove the nuts on the spindle (and possibly circlip, i can't remember which side it on!!). Undo the six screws that locate the freewheel assembly to the cover. You will need to make a tool that uses 2 of the holes in the freewheel assembly to unscrew the cover from the main housing. I used a tool supplied with an angle grinder for changing grinder discs and modified that. Because your hub in already in a wheel there shouldn't be a need to hold it in a bench vice. Once you get the cover moving it should undo ok. Having said that, i've had one cover that locks up because of some kind of threadlock. When you get the cover removed...all will be revealed. I suspect one of the springs has come out judging by the amount of noise coming from it.
Mel

 

[jerrysimon]

Mel,

Thanks I will give it a go.

It does sound like something probably a spring loose/broken scratching the freewheel plate if I interpret that pic you posted correctly.

Regards

Jerry

 

[jerrysimon]

Ok just took a look. The cirlip and screws come off ok. The inside then spins freely. Do you turn the cover anti clockwise looking down on it ?

Also on the tool you use/make do you need to screw it into a couple of holes or just have a couple of steel dowls that fit down into the holes ?

Regards

Jerry

 

[wurly]

Yes it turns anti clockwise. I used some longer screws of the same thread with a couple of nuts to lock the tooling flat onto the cover (if you see what i mean?).I guess the more screws you can use the better chance of removing it. Steels dowels with a countersunk shape would be nice, but i found that using 2 screws worked ok. It all depends to how much work you want to do to make such a piece of tooling.
A bit of force will be needed even a sharp tap with a small hammer. If it loosens ok, then proceed to unscrew it. If it gets tight, stop don't force it. you'll get an idea of how the threads feel as you unscrew the cover.

 

[jerrysimon]

Thanks.

Was looking at one of these though the spacing of the holes I measure is 54mm to centers.

SILVERLINE ADJUSTABLE PIN WRENCH on eBay (end time 16-Apr-10 11:11:45 BST)

Will hunt round and speak to the engineers at work.

Regards

Jerry

 

[jerrysimon]

Or maybe one of these if the centers are right

IMMERSION SPANNER FLAT, LONG HANDLE ,ROBUST on eBay (end time 14-Apr-10 19:11:33 BST)

Damn what a pain

Anyway at least I have another motor to keep me going I guess

Regards

Jerry

 

[jerrysimon]

Well I finally got the motor apart. I used a vice in the end as shown in an earlier link

Now I understand how it comes apart, I am going to make a tool to do it for future use.

Anyway I took out the freewheel and on inspection it all looked fine i.e. it span freely, no broken or stuck up springs etc.

I cleaned the freewheel out with WD40 and used compress air to blow any grit/muck through. I did it at work with one of the engineers and he said best not to dismantle the freewheel as it seemed to run smoothly.

We then re-greased it all and put it back together.

I have been out for a run and it ran perfectly with no rachette sound

Still not 100% sure what the problem was. Maybe one of the springs had slipped and when we stripped it down, cleaned it and regreased it, it solved the problem.

I have some pics that I will post later. They were taken with my phone at work so not brilliant pictures. Now I know how to take it apart, once I make a proper tool to do it I may dismantle it again. I want to build my second spare motor into a wheel first though so I can continue to ride when I strip the first one down again.

Once it was stripped down, I could see how to take the shafts off so can now cut the long one down and also cut off the roller brake fitting more easily with it dismantled.

Having done it I at least now understand more how the thing works and doing it again will not be so traumatic.

Regards

Jerry