Impulse 2.0 problems

Jacq

Just Joined
Jan 12, 2019
2
0
I bought a Kalkhoff endeavour about 6 months ago, and have experienced 4 times in that period that my ebike would not start up in the morning after having used it just fine the day before . Battery shows as charged & until now at some stage it starts working ok again. No rhyme nor reason when that will happen. My dealer has no idea what it is and cannot replicate the fault (sod's law that it has come on again by the time they have it in the workshop). I think it needs to be replaced under warranty. Has anyone ever experienced this problem?
 

soundwave

Esteemed Pedelecer
May 23, 2015
8,877
3,700
yup near every impulse motor fails there was a massive thread on here about it and the only fix offers was endless motor replacements until it was pointed out they only got so many times to fix it or money back under uk trading standards.

i would get a full refund as there not fit for purpose.
 

Jacq

Just Joined
Jan 12, 2019
2
0
Yes, I have read those but they seem to concern the old Impulse motors (mine is only from 2018) and what is described does not seem to match my experience. Mine almost feels like an electrical communication problem between on/off switch, monitor and/or battery, as the display malfunctions (does not light up). It never happens during use but always next morning after having used it fine the day before (and been on charge in between). My bike shop says they have never come across it and they did know about the motor problems in the past.
 

soundwave

Esteemed Pedelecer
May 23, 2015
8,877
3,700
if you can get a refund then it is ur best option as id not bet on any impulse motor it is just not worth the hassle.
 
  • Agree
Reactions: oriteroom

flecc

Member
Oct 25, 2006
41,899
17,535
I'd suspect the connectors between the head unit cable and motor losing connection, a quite common problem. Condensation or forming a diodic layer are usual causes.

Try unplugging and replugging two or three times, preferably spraying them with some switch/contact cleaner while apart. There's a very good chance that will solve the problem.
.
 

Alzibiff

Just Joined
Oct 7, 2018
1
0
63
I have had a similar problem on one of the two Kalkhoff Agattu Excite bikes which we bought last August. On four occasions, the bike has effectively reset itself - mileage goes to zero, clock goes to 00:00, and when I push it out of the garage, no speed shown on the display. This has happened after I have had the battery out for a day or so and wondered whether it had anything to do with the system backup battery losing its connection. (There must be a battery somewhere which keeps the clock ticking when the main power pack has been taken out). After a while, I can get power assist but not until I have gone through the gears a couple of times - I cannot see any rational explanation for this!

My dealer is also perplexed but has agreed to swap the “head unit” under warranty in the hope that this fixes it. I cannot find any technical detail online but what IS the function of the head unit? Is it more than just a display?

I should add that there is no problem when out riding so I have ruled out any intermittent connection issue when the power pack is fitted.
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
1,236
171
Basildon
Nearly all the head units on electric bikes are sophisticated devices. They have a microcontroller in them that performs several important functions ant it communicates with the microcontrollerm in the motor's control board. On most bikes, they work more or less independently and their power wires are shared with the motor's control board so that when you switch on the control panel, it switches on the motor too. That's why your bike can't work when the LCD is off. If the LCD won't switch on or it switches itself off, it's because its supply from the battery has been interrupted.
 

LNEL

Just Joined
Mar 17, 2019
2
0
Yes, I have read those but they seem to concern the old Impulse motors (mine is only from 2018) and what is described does not seem to match my experience. Mine almost feels like an electrical communication problem between on/off switch, monitor and/or battery, as the display malfunctions (does not light up). It never happens during use but always next morning after having used it fine the day before (and been on charge in between). My bike shop says they have never come across it and they did know about the motor problems in the past.
I have the same problem. The on/off switch is dead every morning even though the battery has good charge. The only fix is to connect the battery to a mains outlet and then the switch starts operating. I can disconnect the mains and the on/off switch will operate the bike as normal. However, once I turn off and leave the bike off for more than a few minutes, cant turn on again without re-connecting battery to the mains.
 

Eagle

Esteemed Pedelecer
Aug 31, 2012
377
132
Jacq,
My advice would be to reject the bike and get a refund, or do a swap with a non-Kalkhoff ebike.
 

LNEL

Just Joined
Mar 17, 2019
2
0
Jacq,
My advice would be to reject the bike and get a refund, or do a swap with a non-Kalkhoff ebike.
Thanks Jacq, but unfortunately it's out of warranty. But I guess the lesson is that the German's are not making things the way they used to.
 

Eagle

Esteemed Pedelecer
Aug 31, 2012
377
132
Maybe Kalkhoff have always made them that way, judging by the large number of complaints about their products on these forums.
 

flecc

Member
Oct 25, 2006
41,899
17,535
Thanks Jacq, but unfortunately it's out of warranty. But I guess the lesson is that the German's are not making things the way they used to.
Maybe Kalkhoff have always made them that way, judging by the large number of complaints about their products on these forums.
It's not Kalkhoff that's been the trouble, here's how the troubles came about. Before going into e-bikes they made a fine range of good quality bikes that included the Agattu and Pro Connect models. Deciding to get into pedelecs, they did as two other fine brands, BikeTec of Switzerland and Giant of Taiwan did and adopted the excellent Panasonic crank motor, fitting it to modified Agattu and Pro Connect models.

Over time though the Panasonic unit became increasingly expensive and some German firms began making home grown motors, so Kalkhoff changed to the small German company's Daum motor, calling it the Impulse. That first model was ok, giving no more trouble than any other, but then Bosch entered the market with a much more powerful crank unit. That had it's teething troubles but Bosch dealt with them ok.

However, finding their Impulse outclassed, Kalkhoff went back to Daum for more power and Daum responded with the upgraded Impulse 2 which went a little beyond some Bosch models. That began all the troubles, clearly the unit wasn't handling the extra power without mechanical failures of various kinds, gears, pawls etc. Daum tried to deal with the issues, including some software changes, upgrades and a model change but failed to solve the problems.

With sales slumping, Kalkhoff then also used other motors they could get hold of at short notice, including the Xion and some Bosch motors, making life difficult for their agents who now suddenly needed to be able to handle service on Panasonic, Impulse One, Two and Evo models, Xion and Bosch, a bit of a nightmare.

It's been a very sorry story, but at the core for blame in my view was the Daum company. My reason for saying that is a clear indication that the original unit's design was only just about good enough with no reserve. It operated by starting with a momentary burst of power which quickly phased down to an average level, the software designed to do that.

Buyers immediately hated that, wanting the full power all the time, so a software upgrade was issued to achieve that. From then on a tiny number of that first unit were affected by failure, the first pointer to being marginal where longevity was concerned, so the big power increase for the Impulse 2 dealt the death blow.

But Kalkhoff bikes have always been fine. I had one of the first Panasonic powered Agattu models for over a week for review, gave it a very tough time and reported very favourably on it. If only they'd stayed with that motor none of the troubles would ever have occurred. We have members who've used those originals for commuting since 2007/8 and most wouldn't hear a word said against their bikes. Even their Panasonic batteries have been lasting well over five years while many other battery makes have fallen far short of that.

So by all means buy a Kalkhoff, but not with any Daum sourced motor and preferably with one that's widely used and supported, like Bosch.
.
 
Last edited:

Related Articles

Advertisers