Kalkhoff Cutting Out?

[Cyclezee]

My 2 year old Agattu, used mainly by my son for commuting, developed a fault yesterday. He rode to work as normal and the bike was parked in a warehouse all day. When he came to ride it home, the power lights on the handlebar control went out a few seconds after he started pedaling and he was left without power. The battery was showing 3 lights, so plenty of power left.
I had a quick look last night and took it for a ride, managed to get a 100 yards before the power cut out.

I'm guessing it is a faulty or loose connection, but won't have a chance to investigate until Friday. It has been ridden through some very heavy rain over the last few weeks, so I'm wondering if that could also be a cause, although I think that is unlikely as the Panasonic units as fairly watertight.

Any ideas?

J hn

 

[flecc]

A connection problem is certainly possible John, though it might just be a cell failure since that has the same characteristic, suddenly dropping the voltage to cutoff point. Hopefully not the latter at almost exactly two years old and probably unlikely.
.

 

[Fecn]

I'd try cleaning the battery terminals on the bike - They can build up a layer of grime after a while. I believe someone else on the forum (Aldby perhaps) recently had similar problems.

 

[tillson]

It does sound familiar. This perhaps?

Having said that, it was Aldby who started the linked thread.

 

[Cyclezee]

Tony,

I tried a battery swap which made no difference, so I think I can rule out battery issues, the 2 year old battery is still putting out 8 amps.

Fecn,

Yes, that was me with heavily corroded terminals, have replaced them not very long ago (supplied F.O.C. by 50c), so I don't think that is the problem.

Tillson,

This seems different, the power dies completely, the previous problem was erratic cutting in and out. I'm really not sure yet.

J hn

 

[Barnowl]

I had the same problem on my Cytronex. I thought it was a battery problem but on closer inspection the cut off cable to my brake had broken away and the micro switch was switching of the power for periods of time. Could be something along the similar lines perhaps.

 

[Cyclezee]

Barnowl,

The Agattu doesn't have micro switches to cut power under braking as it is pedelec only, i.e. no pedaling, no power making such things unnecessary.

J hn

 

[Barnowl]

Barnowl,

The Agattu doesn't have micro switches to cut power under braking as it is pedelec only, i.e. no pedaling, no power making such things unnecessary.

J hn

Ahhh - of course. Good luck

 

[Cyclezee]

I have just checked the battery terminal connectors which I replaced in August due to excessive corrosion, and as you will see from the photos the replacement is also corroding!
If you look closely, you will see the plastic around the terminal on the right appears to have melted.



I am assuming this is the problem again? Next step could be to examine the connectors in the battery. They are very difficult to see without opening up the battery. I am slightly reluctant to do this, but as the battery is now out of warranty I might just do that.

When my son returns from work this afternoon with my ProConnect S, I will try the battery from that again and see what happens.

In the meantime I will try contact cleaner to see if that helps.

I am also wondering if the very wet weather recently and presence of moisture around the terminals could be factor in rapid electrolitic corrosion?

J hn

 

[Fecn]

Hi John,

Am I mistaken in thinking that there's a 20A mini-blade fuse buried away inside the wiring sock on the Agattu (not sure if my memory is playing tricks on my this morning). If there's one in there, it'd be worth checking the contacts on the fuse for corrosion too.

 

[Cyclezee]

Hi John,

Am I mistaken in thinking that there's a 20A mini-blade fuse buried away inside the wiring sock on the Agattu (not sure if my memory is playing tricks on my this morning). If there's one in there, it'd be worth checking the contacts on the fuse for corrosion too.

Thanks Fecn,

I don't know about a fuse?
Have just spayed the terminals with contact cleaner and went for quick spin, about a mile uphill, power was steady most of the time, but it did cut out once and I felt it missing a beat 2 or 3 times.
I'm now fairly sure now the problem is with the battery terminals, hopefully I can get replacements for the battery as well as the contact plate.

When my son gets back, I will try the other battery to see what happens.

J hn

 

[tillson]

From your photograph it looks like fretting damage rather than corrosion of the contact surface?

I know that this is of no help to you, but my bike has no hint of contact corrosion on the blades, I have just been to check. I've had it for 18 months and used it all year round so I expect that it has seen as much salt and moisture as your bike. It is difficult to define what excessive is, but does the battery move around in the holder more that you would expect?

I followed JamesC's advice and made a small rubber packer to take out what little movement there was in my battery. But having said that, its still not acceptable if the damage has been caused due to a defective battery holder.

Before you open up the battery, it might be worth bearing in mind that this fault developed whilst you bike was still under warranty and that your current problems may be a continuation of that fault.

 

[Cyclezee]

From your photograph it looks like fretting damage rather than corrosion of the contact surface?

I know that this is of no help to you, but my bike has no hint of contact corrosion on the blades, I have just been to check. I've had it for 18 months and used it all year round so I expect that it has seen as much salt and moisture as your bike. It is difficult to define what excessive is, but does the battery move around in the holder more that you would expect?

I followed JamesC's advice and made a small rubber packer to take out what little movement there was in my battery. But having said that, its still not acceptable if the damage has been caused due to a defective battery holder.

Before you open up the battery, it might be worth bearing in mind that this fault developed whilst you bike was still under warranty and that your current problems may be a continuation of that fault.

Thanks Tillson,

I adjusted the battery holder back in August when I fitted a replacement terminal, so there is very little play now. I will try JamesC's method, but I think the terminals will need replacing in any case. I hear what you say about the battery and warranty and will mention that to 50c as when I speak to them about terminals.

Apart from a few minor problems the Agattu is 2 years old, has done over 5300 miles and is one of the best things I have ever bought.

J hn

 

[Cyclezee]

Yesterday I followed JamesC's advice and fitted a piece of inner tube over the battery contact plate to take up the very slight amount of movement of the battery, it is now very secure but still locks in place easily.
This together with a clean up of the terminals seems to resolved the problem for now.

I still have a concern about the contacts in the battery and after reporting the problem to 50cycles, Tim very kindly offered to call in on his way down to London. He has collected the battery this morning and will get the workshop to have a look at it for me. Great service


J hn