Known Issues & Problems with Kalkhoff Products + Help, Solutions & Fixes

Ann M.

Well-Known Member
No ebike is perfect, this is a thread dedicated to sharing known issues or problems with electric bikes from Kalkhoff as well as any help and solutions you know of. Sometimes that means a DIY fix and other times it can mean a recall, software update or part replacement by a dealer.

Please be respectful and constructive with feedback, this is not a space for hate speech. In many cases, representatives from the company will see feedback and use it to improve their product. In the end, the goal is to enjoy riding and help each other go further and be safer.
There are reports of problems with some Impulse 2.0 motors built during the 2014-2016 model years here and here, I don't speak German but Knacken, Quacken and Klacken don't sound good! The issue sparked discussion on the British and German Pedelec forums about some Impulse 2.0 owners requiring motor replacements. For the 2017 model year Kalkhoff have switched to the Bosch motor for the North America Agattu's.
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There are reports of problems with some Impulse 2.0 motors

Some people that bought their bikes in 2015 and 2016 with the Impulse2.0 motor (Kalkhoff / Focus / Raleigh) had or have now problems.
1. Sometimes after a few miles you can hear a croaking noise while driving up hills with max assistance. It also possible to have after 3.000mi and more. I think, its the bearing of the big white plastic gear.
2. Mostly with higher mileage there can be problems with the pawls in the motor. They start to clack / make clacking noises.
3. With continuously clacking while pedalling, I'm sure your pawls are broken and some small parts are flying around between gears and bearings.

At the end the freewheel can block.

I don't speak German but Knacken, Quacken and Klacken don't sound good!

Knacken / Klacken --> clacking noise

Quaken --> croaking noise

The new motors from Nov 2016 till now have a lot of improvements, larger bearings, better situated grease, new software ...
They are labeled Impulse2.2 - lets see if they are more reliable!
Some confusion about which version of the Bosch motor is fitted to 2017 Agattu's for North America. I received the following explanation from Kalkhoff's brand owner Pon: "The bike does come with a Performance Line Motor. There was a mistake at the factory -- an 'Active Line' plastic plate was accidentally placed over some of the Performance Line motors. We have since mailed the 'Performance Line' plastic cover out to dealers. All 2017 Kalkhoff Agattu bikes come with a Performance Line Motor."
Not prefect is an understatement for me regarding Kalkhoff engines. I spent 6k on my Kalkhoff bike to have 2 motors fail and be replaced with the quacking condition and the problem still persists with little support from Kalkhoff, I’m about to start legal proceedings against the shop that sold me the bike!
Reece123 - I too have had three motors now on my Kalkhoff Endeavour (2015) but, perhaps luckily, the "clacking" problem is now resolved. It's disturbing to hear that you are at the point of legal proceedings against a supplier for resolution of a known problem. Dare I ask what supplier was it? (I bought my Kalkhoff from 50cycles) in the UK - they couldn't have been more helpful.)
We have also seen plenty of issues with the Impulse motors, including the aforementioned clicking noises. Kalkhoff understands that these motors have problems, so they issue warranties on these motors with no resistance. We have probably warranted a handful up to this point.

It was interesting to see Kalkhoff move away from their own motors for 2017 considering they sunk a lot of money into research and development of the Impulse systems. The consensus in the US market was that no one really wanted the Impulse, so they made the move. Definitely glad they did, as Bosch provides an excellent motor system that is extremely reliable.
I bought an Kalkhoff, ENDEAVOUR IMPULSE Speed 11 at the beginning of 2015. Since then I have replaced two motors and now my second battery have given up after only 22 months. I got an offer from my dealer to buy a new battery for "only" 750 Euro! My third motor also have a strange sound which scares me not buing a new battery since I suspect it's the motor destroying the batteries. So what do I do with a useless 3000 Euro bike after only 32 months? Any suggestions. I'm thinking of starting a claim with help from "European Consumer Centres Network".

Anyone who knows were to find the label Impuls 2.2 on the new better motor? I received my latest motor end of 2016 but with an older software installed. Don't know if it is the now better 2.2

Today 2018-01-03 my dealer has respond on my complaint and are willing to discuss some kind of solution. Don't know yet how but it gives me hope.
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I have returned the bike to the dealer and my dealer did put a claim against Kalkhoff and they have given all my money back for the bike! I'm so satisfied how this was solved in the end and it's all thanks to my dealer E24. Now I'm waiting for my new bike to arrive and it's not an Kalkhoff.
I think it was a very good decision @Thomas Gårdelöv ! Although the motor issues were really anoying, the brilliant service at the end keeps the image of Kalkhoff on a high level. Which bike with which motor system will be your next one?
I own a 2014 Focus Jarifa S27 (Speed pedelec 27mph 350W impulse drive)
I am a heavy user 20 miles 5 days a week about 10 thousand miles on this bike.
I have completely destroyed one motor unit and possibly saved its replacement.
My first motor died completely at about 3.5/4 thousand miles and I managed to get a new one under warranty. Before the original died the unit made noises similar chirping leading to creaking cracking sounds I let the noise go on to long and lost drive the motor would run but not drive the cranks.
My second motor started making the noises this week and knowing that it was a bad sound I did not push it and shut the bike down straight away! and pushed it home before the drive gave out.
I tried my luck under warranty again but as expected the answer was no, but I could purchase a new unit at £300 ish.
Being that it was out of warranty I decided to strip the unit down myself.
The gears all seemed fine but there was play on the main nylon gear due to a bearing on the freewheel mech on the shaft, getting to bearing was a bit of a nightmare involving making a tool to pull off a pressed on outer shaft bearing to get to the inner mechanism's bearing which was causing the issue.
This is the point I got a bit annoyed because the bad bearing is not up to the job (it is almost like it is designed to fail.) but also elated because it suddenly became fixable
Also with prolonged use in the state it is in I would have done damage
I am in process of finding a replacement bearing so expecting to get it running again or at least reassembled again this week.
I am also replacing every other bearing in it while it is open.
If it works I will right a more in depth description of what I did but for the moment my advice depends on the situation.
If you are in warranty and hear the sounds then try to break it to get a replacement,
if you are out of warranty then as soon as you here the warning sounds stop because at this point I believe it is possible to fix cheaply leave it to long then it will do other damage.
I bought a kalkhoff Agattu Premium 3 years ago. I had the motor replaced 18 months ago under warranty. The replacement was the new 2.2 version and is under 2 years
warranty. It was Ok for a short while but has gradually deteriorated and although still useable it makes embarrassingly loud cracking noises. The dealer from
whom I bought the bike has been quick to respond in the past and I have now contacted them again regarding my current motor problems. I have to travel about 10 miles to the shop and put up with having no bike while it is fixed. The bike is a top of the range model and cost a lot of money. It is a very nice bike and I like everything about it except the wretched motor. I think I am justified in feeling rather aggrieved at the inconvenience. Should I take a chance on another motor or should I try to get either a replacement bike by another manufacturer or credit ? The bike has been well looked after and is in very good condition but it is 3 years old. Advice by anyone with similar problems would be much appreciated.
Kalkhoff warranty Impulse motors made after 2017 for 3 years How much are they asking to replace the motor and will they warranty a replacement motor for 3 years? Is so then divide the purchase cost by 3 and that’s your annual opportunity cost for continuing to own your existing Kalkhoff ebike, if that’s not something you want to do what sort of trade in value will your Kalkhoff dealer offer on a new ebike with a different motor? Given they sold you a bike with a known manufacturing defect you could try asking them to honor the bicycle blue book value on a 2016 Agattu
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Hi guys, just checking whether anyone has come across a sudden 'loss of contact/power' type issue in the Impulse 1 motor? I have a 2014 Endeavour, and although I had a replacement motor as a warranty issue early in the bike's life (self fitted) the bike has been great until the other day, when it suddenly refused to offer anything by way of assistance; furthermore, the lights on the bike no longer work, although there is power to the switch gear and the console/info screen. The battery is completely up ( we have 2 of these bikes, my partner bought one in 2016 to keep up with me!), showing a charge of 41,3v, and either battery module works my partners bike without issue.

As you may imagine, my preliminary thoughts were that a possible connection issue in the wiring might be the cause of the loss of assistance, though having taken a superficial look over the connections beneath the plastic battery base cover plate has revealed nothing out of the way.

The sudden loss of 'connection' seems to have happened while the bike was secured to my bike rack in transit home from a remote tour around a loch in central Scotland, when it worked without problem around the 33 mile route, but when we tried to take a short tour at home the other day it refused to come alive, save the power to switches and display, which is what made me think that a wire may have been vibrated or otherwise come loose.

Needless to say, I have not opened up the motor itself, but am awaiting any advice from Cloppenburg meantime. If the problem is of a terminal nature (I know the early motors were beset with reliability issues), can anyone give advice as to the reliability of the most recent update 2.3 motor, as I'm now wondering whether it will either be fixable or not, though of course I'll await a response from Kalkhoff HQ before either attempting a fix myself or removing the motor and sending to wherever they recommend for investigation/service. I see that 50cycles (where we bought 3 Kalkhoff ebikes) no longer seem to be distributor for Kalkhoff cycles, but are offering to sell the latest replacement 2.3 motors; of course I need to know whether my own 1.0 motor will repair before committing to either a new motor or the much greater commitment to a replacement ebike. I've hitherto been very happy with the bike as a whole, and despite the initial problem with the first motor, the second one has until now ha been reliable in every aspect, and the bike itself is of very good build quality.

Any advice or pointers very much appreciated meantime, thank you.
Hi @Freewheeler,

in my blog Pedelecmonitor I have a biker with an old 2012 Kalkhoff (exact model is unknown). He told me about the poor quality and robustness of the first ebikes with Impulse1 system.

He reported a similar failure. The root cause was a very stiff cable connection between the remote at the bar and the entry into the bicycle frame that had inner cracks due to the UV light and the vibrations over several years. He dismounted the motor and checked all cables. After replacing the old stiff cable with a more felexible everything worked fine again.

Do you have a bike with a display or just a LED remote?

Impulse Display (small)

Ha, thanks for this, mine was a 2014; all a bit academic now, as have since fitted new imp 2.3 motor (late 2017 d.o.m.) and running sweet as a nut, which suggests my cabling was/is not the issue.

Okay down a little for a new motor, but it is running and running very sweetly indeed, so S,lies all Roding, and many thanks to Dave at 50C for his advice and help??
I've been very disappointed with the Kalkhoff ebike I bought from 50 cycles 5 years ago, costing £1700. Because of an injury it has been very lightly used until recently. Now there appears to be a problem with the motor,and 50 cycles response is that they are no longer Kalkhoff dealers so can't get parts, so try google for another dealer!

I've seen discussions on here about a problem with kalkhoff motors in the early 20-teens. I'd be grateful if anyone could help me (1) identify the type of motor my bike has, and if possible - suggest an alternative motor and someone who might fit it: I live near oxford

thanks for any help you can offer!