Kalkhoff pro connect - new panasonic motor or repair?

[flecc]

Mount the motor sprocket on the drive shaft and get a good grip on it with a rag or preferable use a chain wrench to grip it.

If the casing is open use a piece of soft wood to jam between the nylon cog and motor shaft gear, then use some effort to turn the sprocket clockwise. It should jam and refuse to move.

Don't use so much effort that the nylon gear is damaged, a moderate effort is enough to ascertain the motor should drive the sprocket.

If the case is closed you could access the nylon gear teeth by taking off the motor and use something through the motor shaft hole to jam it from turning, but again, be careful to avoid damaging that nylon gear.

 

[Deleted member 4366]

How to check if clutch is slipping under load?

Put it all back together and ride the bike!

It's still possible that the clutch is sticking. It's definitely worthwhile to access the rollers and regrease them. Have a look at the surface they grip on to see if there's any sign of slipping.

One other possibility I can think of is that the motor turns backwards. I'm not familiar with the Panasonic electronics, so I can't say how it can happen, but it is a possibility.

 

[landyguy2]

How to access the rollers
Do I need to remove the bearing on the shaft though the nylon gear.

 

[tillson]

When pressure on pedal motor makes a whirring noise but no assistance

Are you saying that if the bike is stationary and you apply pressure on the pedal, as if just about to set off, the motor whirrs as if running but the motor drive is not being transferred to the chain? It's not entirely clear from your description and accuracy on this point could make diagnosing the problem easier.

 

[landyguy2]

Yes exactly that

 

[landyguy2]

And when riding bike the same whirring but no apparent assistance

 

[flecc]

How to access the rollers
Do I need to remove the bearing on the shaft though the nylon gear.

I've never accessed them on the new unit since none has ever given any clutch trouble at all in the seven years they've existed,

The old unit used to suffer it jamming but never slipping, but that was contained within a steel gear so may have somewhat different mounting, Certainly one bearing would have to pulled from the shaft. I might have the opportunity to check this out tomorrow if there's time, but i already have a full schedule at present.

Meanwhile this link shows the old unit's needle roller clutch assembly and it's removal.

 

[martin@onbike]

Sounds silly, but you did make sure the chain hadn't jumped off the drive sprocket ?-seen that before a couple of times.....

 

[tillson]

Yes exactly that

Well if the motor is turning but there is no apparent drive to the chain, the problem has to be mechanical, or am I looking at this too simplistically?

So, either:

1/ The motor worm gear isn't driving the large nylon gear.

or

2/ The freewheel clutch isn't engaging with the splined motor output shaft.

or

3/ The splined motor output shaft isn't engaging with the chain drive sprocket.

or

4/ The chain drive sprocket isn't engaged with the chain ( Martin's suggestion).

Any other suggestions? Are we sure that we have isolated all of these possibilities?

 

[flecc]

A motor with a Hall sensing error can make a noise somewhat like it is running so a Hall board is on it's way so that can be checked if nothing else is found, since tat is very simply checked.

As d8veh suggested, the motor running backwards would produce the same, but since the Hall board wasn't displaced that seem unlikely.

Another very remote chance is that the magnetic rotor has lost it's bond with the drive shaft, leaving only the rotor turning, but that really is very, very unlikely.

 

[landyguy2]

I will update when I have tried the Hall sensor after it arrives
Thanks for all your help and comments so far

 

[flecc]

How to access the rollers
Do I need to remove the bearing on the shaft though the nylon gear.

I very much doubt this could be the problem. However:

To get at the freewheel, first mark the nylon wheel side to show which way it goes back. If reversed the motor can never drive the bike. Place a couple of screwdrivers behind the nylon wheel to lever the rear bearing out of the crankcase half, it will come out easily. Then on the sprocket splines side of the shaft pull off the large bearing*. Behind it is a circlip, remove that and pull the nylon wheel off the needle roller bearing cage.

Do not pack it with grease when reassembling, this type should only have the the very lightest smear and what's there should be plenty. As far back as 2001 these have never needed added grease, they will slip if packed with it. Make sure you put the nylon wheel back on the right way.

* Use a bearing puller if you have one. If not, try two bars or rods placed behind the bearing on either side, and with the shaft's splines end on the surface, press down evenly on both sides of the bars. If this doesn't work, a friendly local garage or m/c dealers will pull it off the shaft for you in seconds.

 

[landyguy2]

I have fitted the new hall sensor and reassembled - hoping for improvement but still the same.
However I have tried the bike without the tensioning gear on so there is no chain on the chain drive sprocket and it turns when pressure is put on the pedals.
This appears to point to the clutch slipping to me.
The only thing I did not take apart was the clutch as it appeared to be ok. Bugger.
Anyone any ideas.

 

[tillson]

I have fitted the new hall sensor and reassembled - hoping for improvement but still the same.
However I have tried the bike without the tensioning gear on so there is no chain on the chain drive sprocket and it turns when pressure is put on the pedals.
This appears to point to the clutch slipping to me.
The only thing I did not take apart was the clutch as it appeared to be ok. Bugger.
Anyone any ideas.

My motor did exactly the same when I applied pressure to the pedals, it turned but there was very little torque, hence very little power.

 

[landyguy2]

What was the solution

 

[flecc]

Tillsons was an electrical fault in the sealed main board leaving it permanently with very low power. The solution was a replacement unit.

You may have the same problem.

As I said before, clutch slip on these is unknown and very unlikely. By all means open up the unit and try to force a slip manually, but my betting is you won't be able to.

 

[Deleted member 4366]

If he can hear the motor going when the sprocket is stationary, something is slipping. Simple logic!

 

[landyguy2]

If the clutch is slipping under load is there anything that can be done or does anyone have a nylon gear and clutch assembly

 

[Deleted member 4366]

Tilson should have one. I can't understand why you didn't look at your clutch when it was in front of you. When you see it, it might be obvious what you have to do.

 

[flecc]

We don't yet know if the motor is actually turning.

In this post and my answer to you an electrical fault was indicated and that was not resolved, so it could be a board failure as with Tillsons.

In this post, you said turning off and on got it going again, once more indicating an electrical fault. And in that same post you also tested the clutch by ascertaining the sprocket drove the motor in reverse, showing the clutch was not slipping.

The outer of the clutch is usually moulded into the nylon gear wheel on these. The inner is the shaft itself. I've got one for you if it proves necessary, but as the above shows, that is very unlikely.

I've given the stripping procedure above on this link, but manually test it again first.