Kalkhoff initially dissapointing; advice please.

itsmepht

Finding my (electric) wheels
May 4, 2020
9
0
Hi, I'm new here, but have learnt a lot from the site. Thanks!
Have just managed to fulfil an ambition and buy ebikes for myself and my wife. Hers, new and surprisingly cheap. A Basis Dorchester. Also quite good looking.
Bought this to see how a 250w machine would perform, and was very pleasantly surprised. It is 'electric assisted' with a twist grip throttle, and took me up a short sharp hill very easily.
I then found and bought myself a Kalkhoff Pro Connect on Ebay, encouraged by many positive reviews. It is also 250v ( I think) with an 18ah battery. Taking it for a ride, my wife dissapeared into the distance, and I had to push it up the hills. It just dosnt have the poke I expected.
The battery seems OK, fully charged and reading 29v on a voltmeter. There is an 8 speed hub gearing, works Ok altho a bit gratey in lowest gear.
Am I correct in guessing that my wifes system is more akin to a fully electric machine, and while it requires the cranks to rotate, no particular effort is required, whereas mine is pedelec, and responds pro rata to the pedal power being put in by the rider?
Personally, I used to race on the track as a youth, and had the legs. ('The older I get, the faster I was'). But years behind a desk staring at a screen has atrophied those muscles, to my intense regret. Getting on an ebike seems to me a terrific way of postponing the Zimmer frame and the Stannah stairlift.
It may be that I am so weak in the legs that the system is not getting the signals about the power I am inputting that it needs to push me up the hills? Or something is wrong with the machine.
So, my question is, how can I find out? I'm in Monmouth, just over the border in Wales. Happy to take it to an expert, but also aware that they might be thin on the ground.
Thanks for reading this far, and for any advice you can offer.
 

Jonah

Esteemed Pedelecer
Aug 23, 2010
882
246
EX38
Hi, I'm new here, but have learnt a lot from the site. Thanks!
Have just managed to fulfil an ambition and buy ebikes for myself and my wife. Hers, new and surprisingly cheap. A Basis Dorchester. Also quite good looking.
Bought this to see how a 250w machine would perform, and was very pleasantly surprised. It is 'electric assisted' with a twist grip throttle, and took me up a short sharp hill very easily.
I then found and bought myself a Kalkhoff Pro Connect on Ebay, encouraged by many positive reviews. It is also 250v ( I think) with an 18ah battery. Taking it for a ride, my wife dissapeared into the distance, and I had to push it up the hills. It just dosnt have the poke I expected.
The battery seems OK, fully charged and reading 29v on a voltmeter. There is an 8 speed hub gearing, works Ok altho a bit gratey in lowest gear.
Am I correct in guessing that my wifes system is more akin to a fully electric machine, and while it requires the cranks to rotate, no particular effort is required, whereas mine is pedelec, and responds pro rata to the pedal power being put in by the rider?
Personally, I used to race on the track as a youth, and had the legs. ('The older I get, the faster I was'). But years behind a desk staring at a screen has atrophied those muscles, to my intense regret. Getting on an ebike seems to me a terrific way of postponing the Zimmer frame and the Stannah stairlift.
It may be that I am so weak in the legs that the system is not getting the signals about the power I am inputting that it needs to push me up the hills? Or something is wrong with the machine.
So, my question is, how can I find out? I'm in Monmouth, just over the border in Wales. Happy to take it to an expert, but also aware that they might be thin on the ground.
Thanks for reading this far, and for any advice you can offer.
I’m guessing it’s an old Kalkhoff with the 26v Panasonic motor / battery since this would read 29v if fully charged. If this is not the case, then the battery is the problem. If Panasonic, that’s a good thing since the replacement Impulse motor was problematic. Perhaps you can send a photo of the bike and the control system. The assist system will feel different to the other bike but should still offer decent help in full power mode. If You aren’t feeling much assist then something might well not be working correctly. Does it have 3 power settings? Can you notice the difference? Does power kick in as soon as you start pedalling?
 

itsmepht

Finding my (electric) wheels
May 4, 2020
9
0
I’m guessing it’s an old Kalkhoff with the 26v Panasonic motor / battery since this would read 29v if fully charged. If this is not the case, then the battery is the problem. If Panasonic, that’s a good thing since the replacement Impulse motor was problematic. Perhaps you can send a photo of the bike and the control system. The assist system will feel different to the other bike but should still offer decent help in full power mode. If You aren’t feeling much assist then something might well not be working correctly. Does it have 3 power settings? Can you notice the difference? Does power kick in as soon as you start pedalling?
Thanks . I think it is the Panasonic, from other info on the system, although it is branded Derby. I will send photos in the morning. It does have 3 power modes.
Yes there is a difference, it bowls along very nicely on the flat, but any sort of an incline, I'm struggling - or walking. Even in lowest gear. Vendor seemed very straight, and claimed he could climb anything, but he was lighter and much fitter than me. Power dosnt seem to come in very powerfully when starting off.
The upside is that the strong pedalling i had to do, has got the lactic acid in my legs goind, which must be a step in the right direction!
 

flecc

Member
Oct 25, 2006
52,763
30,349
The 26 volt Panasonic units are not powerful compared with many later e-bike motors, so there may not be anything wrong other than it being disappointing compared with some others.
.
 

itsmepht

Finding my (electric) wheels
May 4, 2020
9
0
It would be interesting to compare with another Kalkhoff. Is there any way to upgrade my system if there is nothing wrong?
Thanks
 

flecc

Member
Oct 25, 2006
52,763
30,349
It would be interesting to compare with another Kalkhoff. Is there any way to upgrade my system if there is nothing wrong?
Thanks
Kalkhoff have used several different motors and generations of them , so only comparing exactly the same thing would help. To help I need to know exactly if you have the Panasonic unit that they used from November 2007, so here's two photos of one from low on the left, without and with chainwheel. Is yours exactly the same in every detail?

New Left hand side.jpg

crankcase.jpg
 

itsmepht

Finding my (electric) wheels
May 4, 2020
9
0
Kalkhoff have used several different motors and generations of them , so only comparing exactly the same thing would help. To help I need to know exactly if you have the Panasonic unit that they used from November 2007, so here's two photos of one from low on the left, without and with chainwheel. Is yours exactly the same in every detail?

View attachment 35640

View attachment 35641
This does look the same as mine, but am uploading similar photos. I am reasonably confident that there is not enough power being delivered. Its deceptive, because starting off downhill, its a heavy bike so does take off quickly, but then does die given any sort of slope up needing a lot of pedal input. The 3 power settings do not seem to make a lot of difference. I could get it to Bristol if there is an expert there? Thanks again.
 

Attachments

flecc

Member
Oct 25, 2006
52,763
30,349
Yes, that is the same 2007 model Panasonic unit. Derby Cycles gmbh is German parent manufacturing company of many brands, including the Kalkhoff name.

I doubt there's anything wrong with yours since it has those characteristrics of good initial takeoff power but flagging as the speed increases. It's a function of the Japanese pedelec law that they were designed to, where the maximum power is only delivered at low pedal rotation speeds and starts to reduce above 9.4 mph (15 kph).

You can read about that on this link in my Panasonic support website.

Let me know you reactions after reading the whole section on the Japanese law and its effects in all gears and I'll let you know what may be possible.
.
 
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itsmepht

Finding my (electric) wheels
May 4, 2020
9
0
Yes, that is the same 2007 model Panasonic unit. Derby Cycles gmbh is German parent manufacturing company of many brands, including the Kalkhoff name.

I doubt there's anything wrong with yours since it has those characteristrics of good initial takeoff power but flagging as the speed increases. It's a function of the Japanese pedelec law that they were designed to, where the maxium power is only delivered at low pedal rotation speeds and starts to reduce above 9.4 mph (15 kph).

You can read about that on this link in my Panasonic support website.

Let me know you reactions after reading the whole section on the Japanese law and its effects in all gears and I'll let you know what may be possible.
.
That is fantastic information, beautifuly explained and much appreciated. To summarise, to get the best assistance up hills, I need to be in the highest gear and the high power mode, and be pedalling slowly, at low spped?? The opposite of what intuition might suggest. This might suggest that changing the rear sprocket to one with less teeth would be helpful. However I am not sure that all is well with my machine. Before having to get off and push, I would have been pedalling and travelling very slowly with maximum human power- that is where the power should be at its maximum - surely? I am not talking about anything like 1 in 3, or 4.
I think I should go and do a bit of a test, trying the same bit of road and modest hill in various different modes, including with power turned off, and photograph the hill. That would enable you to make a judgement on whether there is a problem or not.
It seems to me that I have three options. 1) remedy the defect, if there is one, 2) Upgrade system to your recommendations. 3) Swap the bike for something that will work for me.
Thanks again.
P.
 

flecc

Member
Oct 25, 2006
52,763
30,349
To summarise, to get the best assistance up hills, I need to be in the highest gear and the high power mode, and be pedalling slowly, at low speed?? The opposite of what intuition might suggest.
That's it exactly, plus bear in mind that this is a low power motor anyway, only delivering 250 watts average at best. Most e-bike motors deliver at least 400 watts actual power, some as much as 600 watts. Below is a graph showing your power delivery over time and you'll see that the bulk of it is at around 250 watts in the middle of the 200 to 300 band and with only brief spikes going higher and much of the power lower in the 100 to 200 band. (Sorry the copy is a bit indistinct):

panasonic_power_graph.jpg
 

itsmepht

Finding my (electric) wheels
May 4, 2020
9
0
That's it exactly, plus bear in mind that this is a low power motor anyway, only delivering 250 watts average at best. Most e-bike motors deliver at least 400 watts actual power, some as much as 600 watts. Below is a graph showing your power delivery over time and you'll see that the bulk of it is at around 250 watts in the middle of the 200 to 300 band and with only brief spikes going higher and much of the power lower in the 100 to 200 band. (Sorry the copy is a bit indistinct):

View attachment 35647
OK; Seems like I made a bad choice. But should I do my suggested test anyway, just in case? And is there a remedy / upgrade? I am amazed that if all is well, that this bike could have gained any buyers, let alone gaining (or so i believe) such a good reputation!
 

flecc

Member
Oct 25, 2006
52,763
30,349
OK; Seems like I made a bad choice. But should I do my suggested test anyway, just in case? And is there a remedy / upgrade? I am amazed that if all is well, that this bike could have gained any buyers, let alone gaining (or so i believe) such a good reputation!
As power assist only, lower powers were more common at the time these were introduced and this unit was the only sophisticated crank drive unit at that time from two bike makers. That later changed with powerful units from Daum, Bosch and others and the Panasonic unit soon stopped being used outside of Japan.

However, even if faulty no repair of such a fault is possible, since repair is only by replacement of the whole unit and no spares are available. The circuit board is encapsulated and sealed into the crankcase side.

There is a way of increasing the power but it's far from easy to do and risky, the unit possibly being short lived and failing. I've found it not very satisfactory too, the increase being quite small.

Have a look near the foot of the page on this link at paragraph two of Performance Enhancements, then at Power Increase under the 26 volt units.
.
 
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Jonah

Esteemed Pedelecer
Aug 23, 2010
882
246
EX38
I had a Raleigh with this motor traded in with me some years ago which I used for a bit. It was a delight to ride on flat trails, smooth and quiet. But, as you have found, lacking in oomph up the hills without a lot of user input. Suited to flattish areas. Nice bike in the right circumstances.
 
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itsmepht

Finding my (electric) wheels
May 4, 2020
9
0
As power assist only, lower powers were more common at the time these were introduced and this unit was the only sophisticated crank drive unit at that time from two bike makers. That later changed with powerful units from Daum, Bosch and others and the Panasonic unit soon stopped being used outside of Japan.

However, even if faulty no repair of such a fault is possible, since repair is only by replacement of the whole unit and no spares are available. The circuit board is encapsulated and sealed into the crankcase side.

There is a way of increasing the power but it's far from easy to do and risky, the unit possibly being short lived and failing. I've found it not very satisfactory too, the increase being quite small.

Have a look near the foot of the page on this link at paragraph two of Performance Enhancements, then at Power Increase under the 26 volt units.
.
All understood. I am not going near the electronics, especially given your provisos. I might put a smaller sprocket on, but feel I should look for something more suitable, and in the meantime learn the contra-intuitive way of riding, and also strengthen up my legs. I note that if the bike is faulty, then no repair is possible anyway; a bit of an indictment in itself. I guess the positive reviews I found on this bike must have been for models with the later motor systems.
There seem to be a lot of 'poo-traps' with second hand, or even new , e-bikes, and a vast plethora of different variations. Batteries, motors and electronics all could be dodgy, and non- repairable / non replaceable as well as hard for a non-specialist to detect or diagnose. Outside the topic of this thread, and probably covered somewhere on this site, but how on earth does a second-hand buyer navigate through this jungle??
Huge thanks anyway; its good to understand!
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
19,991
8,173
60
West Sx RH
Easiest bike usually to repair are generic China controller kits with PAS cadence sensing even if you can't buy the same controller you can buy alternatives available and get the bike running for a cost of £60 - £100.
Companies like Woosh, Wisper, Oxygen, Juicy etc, etc who are ebike designer /producer and vendor will keep spares.
 

flecc

Member
Oct 25, 2006
52,763
30,349
There seem to be a lot of 'poo-traps' with second hand, or even new , e-bikes, and a vast plethora of different variations. Batteries, motors and electronics all could be dodgy, and non- repairable / non replaceable as well as hard for a non-specialist to detect or diagnose. Outside the topic of this thread, and probably covered somewhere on this site, but how on earth does a second-hand buyer navigate through this jungle??
All very true. In fact the repair by replacement policy is true of all the sophisticated crank motor units, but its for very good reasons. Bicycle shops simply don't have the necessary expertise to deal with the faults that might occur with complex units. Their cycle mechanics are no better placed than owners to cope with them.

So from Panasonic onwards the policy has been to design for maximum reliability and life and it has to be said that has usually worked well. We've got members who've used these e-bikes for many years with excellent reliability, even for daily commuting. Indeed I owned an earlier model myself for six years, then sold it to another member who after a couple of years sold it on again in perfect working order, so we know it worked well for at least eight years.

It's for these reasons that I created my Panasonic support web site so that some repairs were made possible. That's enabled many of these bikes to be put back on the road, often at a decade or more old, sometimes by salvaging spares from other failed units. The best outcome on one occasion was getting two models back on the road out of three, with the third re-created from the remaining parts and donated to a bicycle museum!

But if buying second hand do as Neale says and buy a hub motor model using generic components. They are easily and cheaply repaired by anyone capable of using basic tools with advice from sites like this one. But be prepared that you might need to buy a new battery since a failing battery and its replacement cost is why so many get sold after a year or three.

And always try before buying to see if one suits.
.
 

itsmepht

Finding my (electric) wheels
May 4, 2020
9
0
UPDATE ! All forgiven ! (mostly.)
Thanks to advice here, went for a further ride yesterday, and experimented on riding technique, with result that I got up some fairly consideable hills.
First thing was that the hub gears, unlike deraileur, needs a momentory hesitation on pedal pressure to allow it to change. Second, was noticing the different power delivery with speed, and working with it. Third was the quite subtle interplay between cadence, gear and power delivery; bit of an art to get the best from it.
I think the bike would be not as good as many for getting from a to b, but excellent for exercise. Once in the slow speed, high power mode, I had to contribute some muscle power, but it assisted and climbed up OK, although at walking speed or less. That is exactly what I need at present, to get some fitness back, so apologies Kalkhoff machine for misjudging you, and thanks again Pedelecs for the education.
But... I am apprehensive about the non-repairability of the bike; it seems that any problem and it will be sudden death; so I will be looking to repace it at some point. An Orbea Gain??