Ongoing reliability of Kalkhoff/Focus Impulse 2 motors

Tomtomato

Esteemed Pedelecer
Apr 28, 2015
388
196
Reading the Derby Cycle press release of the Impulse Evo release is, I think, interesting:

http://www.derby-cycle.com/en/press/press-releases-brands/single-view/view/always-one-idea-ahead-with-kalkhoff-almost-everything-is-new-1.html

===== some abstracts ==============
More powerful, quieter, more durable: the new Impulse Evo drive

Thanks to a supplementary cadence sensor, the Impulse Evo assists the rider even more smoothly. All the components of the Impulse Evo motor are designed with durability in mind: the gear unit has been reinforced, the new deflection shaft and the new drawn-cup roller clutch are even sturdier, and the innovative multi-tooth axle ensures a secure crank assembly.
================================

The vocabulary used indicates a lot of work/focus on durability/reliability... as if the previous version (Impulse 2) needed some work.
 
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Will Tinker

Pedelecer
Apr 14, 2015
221
163
I'm not sure what to make of this thread, of Kalkhoff, or of the e-bike market in general.

This is not intended as a criticism aimed at anyone. I'm simply not sure.

Here is what I am sure of:

Positives

1) My Impulse 2 motor (on my Pro Connect 9) has completed almost 2,000 miles. I don't think a motor failure is imminent, so I think it will likely go quite a bit further.
2) The Yamaha SyncDrive motors on my previous e-bike(s) (Giant Prime E+ 2014 and 2015 models) managed nothing like this mileage. The first was a bag of bolts from purchase. The second began to fail after around 900 miles.
3) To their credit, Kalkhoff have now acknowledged a fault. 50Cycles have assured me, repeatedly, that if my motor fails they will replace it without a question asked. I have no reason not to believe them.

Negatives

4) There are occasional clacking, chain-slippy (but not actual chain slip) moments riding my Pro Connect 9. I'm a bit disappointed about this considering the cost of the bicycle.
5) Kalkhoff did not immediately acknowledge a problem.
6) My bike cost £1800. That's a huge amount of money for a bike. Kalkhoff have a reputation for making e-bikes at the premium end of the market. But look at the breakdown of components on my 'premium' bike:

Shimano Deore Gears - £25 entry level
Shimano Alivio Shifters - £25
Shimano M396, hydraulic disc brakes - £30 entry level

I'm not claiming they are bad components - they aren't. But what constitutes the bulk of the hefty price I paid for my bicycle?

I'm not against companies making a tidy profit on their products. Not at all. But, now that I know a little more about bicycles (than I did when I first began purchasing my commuting bikes), I'm disappointed in what to me is a lack of perceived value in what I have. I don't want or expect entry level components on a premium, expensive product.

I should make it clear that the Giant bikes I had prior were similar in their use of entry-level parts (that and they broke down a lot).

So, Kalkhoff. If you want me to purchase another one of your bikes, please:

* Make me confident it's hard as nails and won't break down in a hurry
* Be a bit more generous in what you provide for the price-tag.
 
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nemesis

Esteemed Pedelecer
Mar 14, 2011
516
340
Why are the S class motors more expensive than the legal 250w versions ?,we are told that the internals are stronger because of the higher speeds but i don`t think that is true.
 

reggie_electric

Finding my (electric) wheels
Dec 15, 2015
23
8
40
The 2016 year model was released to buy in august 2015 in europe and the first ones were in the uk in november,i know because i had one but sold it because i prefered the mtb i already had.
It would be worth having a look on the german forums to see if any failures have occured with the latest motor.
My Agattu is a 2016 model which I got very early but as has been pointed out, the same as the earlier models in terms of the Impulse 2 motor. I considered the Evo models but couldn't afford the price tag, having already blown my initial budget, and actually didn't want to run the risk of something very desirable getting nicked. The Agattu is more workmanlike than sleek.

I bought my bike as it was marketed as a commuter bike, which implies regular use. I use it everyday 9 miles each way, and as I live in Edinburgh it gets its fair share of hills. I ride it sensibly in terms of gear selection, use of power and loads. I will monitor closely if my new second motor lasts, luckily I am using it enough so that it gets to a high enough mileage within the warranty period for any failings to occur while they're still covered.

Like someone else said, there are a lot of ebikes on the market but some just won't have the same power. But reliability and peace of mind is needed too.
 
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Roger R

Pedelecer
Jul 6, 2015
50
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Hi, thanks for starting this thread and raising this important issue again. As you correctly stated above I bought my Pro Connect 10 last year and the motor started failing within weeks. I think going up a steep hill in high power initially caused the problem. I stuck with it and took video recordings of the problem which I posted on YouTube (you should find them quite easily) and sent to 50 cycles. They eventually agreed to replace the motor, it had done 1000 miles by then (within 6 months). They paid for replacement and fitting but I had to bring it over from North Wales and spend an overnight in Loughborough.

Since I've had the new motor fitted I've never had it out of Eco - I daren't based on feedback in these forums. If there were enough people we could threaten a Class Action against Kalkhoff although that would take a lot of organising, time and energy. Probably never going to happen.

So I'm still happily riding my bike but being very careful not to push the motor at all!

Sent from my Nexus 9 using Tapatalk
 

reggie_electric

Finding my (electric) wheels
Dec 15, 2015
23
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I think going up a steep hill in high power initially caused the problem.

Since I've had the new motor fitted I've never had it out of Eco - I daren't based on feedback in these forums.

So I'm still happily riding my bike but being very careful not to push the motor at all!

Sent from my Nexus 9 using Tapatalk
Doesn't the instruction manual encourage you to keep the bike in a high gear to get the power to go up hills? There requiring full power? If so it's an unusual way to ride a bike as normally you'd wind down to a low gear and spin a lot on a non e-bike.

I don't think there should be ways you can 'break' the bike, if it's tested and developed properly.

Like you say, it's difficult if things go wrong as most of us don't live next to an authorised dealer.
 

Tomtomato

Esteemed Pedelecer
Apr 28, 2015
388
196
I think going up a steep hill in high power initially caused the problem.
I think you may be right: I first heard some clicking noise on my Kalkhoff Pro Connect S10 when I was going up on a fairly long and steep hill. The motor was in high assistance mode (as one would expect).

The second motor made some loud clacking noise for a few seconds when I was going up another hill, and then started losing assistance progressively after that. I guess one or several sensors got damaged.

We are not talking about using the bike in steep mountains, so the bike should be perfectly capable to handle a steep hill for five minutes, in high assistance mode (else what's the point of an electric-assisted bike!).
 

Tomtomato

Esteemed Pedelecer
Apr 28, 2015
388
196
We are told that the internals are stronger because of the higher speeds but i don`t think that is true.
That's a very good point: if the internals are stronger on the S version of the Impulse 2 motor (350 watts), then they should just replace faulty motors by that version, and reduce its output via the electronic controller, as most people want to stay legal.
 

Tomtomato

Esteemed Pedelecer
Apr 28, 2015
388
196
5) Kalkhoff did not immediately acknowledge a problem.
No, they didn't.

It's only when various people started reporting issues on this forum and others that they finally asked Kalkhoff, and Kalkhoff said that they had an issue with the Impulse 2 motors.

6) My bike cost £1800. That's a huge amount of money for a bike.
But what constitutes the bulk of the hefty price I paid for my bicycle?
The hefty price is just coming from the margin they make on your bike. The non-powered, push version of the bike is probably worth £400 (and I am talking retail price, with manufacturer and retaile margin included). Look for instance at the Kalkhoff Voyager range, which looks similar to the Pro Connect Impulse bikes.

Link: https://www.fahrrad-kaufen-online.de/kalkhoff-voyager-21g-shimano-acera-21-gang/a-39583/?ReferrerID=121

Add the motor and battery (11Ah), and that's probably another £600, so we are looking at a margin of £800 or more (45%), between Kalkhoff and 50 Cycles. Margin is even higher on more expensive bikes.
 
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Why are the S class motors more expensive than the legal 250w versions ?,we are told that the internals are stronger because of the higher speeds but i don`t think that is true.
I don't know the Kalkhoff range, but in general I don't think you'll find an S Class bike and a legal one with the same spec other than the motor. So the 2 aren't directly comparable. There are a number of other upgrades that need to be made to the bike for it to be able to be legally classed as an S Class bike and used legally in the countries where they can legally be used, like brakes, license plate holders and more. So if you give me an example of 2 bikes you're comparing I can probably explain the price differences for you.

If you comparing UK prices, its also possible a company is inflating the price of the sPedelec's they are selling simply because they can, because a high % of shops won't sell them for a number of previously discussed reasons. So they might just be adding to their margin to make them feel more comfortable about the risk they are taking.
 
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Will Tinker

Pedelecer
Apr 14, 2015
221
163
Re: 50Cycles stocking other bikes... yes, I've noticed that too. The number of competing brands to suddenly appear seems to indicate a change of strategy for them, at least.

They've started stocking the Giant Primes. God knows what their return rate will be like...
 
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Will Tinker

Pedelecer
Apr 14, 2015
221
163
Hi, thanks for starting this thread and raising this important issue again. As you correctly stated above I bought my Pro Connect 10 last year and the motor started failing within weeks. I think going up a steep hill in high power initially caused the problem. I stuck with it and took video recordings of the problem which I posted on YouTube (you should find them quite easily) and sent to 50 cycles. They eventually agreed to replace the motor, it had done 1000 miles by then (within 6 months). They paid for replacement and fitting but I had to bring it over from North Wales and spend an overnight in Loughborough.

Since I've had the new motor fitted I've never had it out of Eco - I daren't based on feedback in these forums. If there were enough people we could threaten a Class Action against Kalkhoff although that would take a lot of organising, time and energy. Probably never going to happen.

So I'm still happily riding my bike but being very careful not to push the motor at all!

Sent from my Nexus 9 using Tapatalk
I'm almost on 2,000 miles, and mine has been run in 'Power' mode 90% of the time.

I doubt using Eco will make much difference. Probably a good idea to use a suitable gear depending on the incline, but that's about it.
 
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reggie_electric

Finding my (electric) wheels
Dec 15, 2015
23
8
40
Does anyone's chain keep going round when they are pedalling? I'm noticing it happen with my new motor, either it doesn't have much resistance itself or the hub gear is tightening up. I had noticed it now and again but confirmed my suspicion today when taking a rearward facing video. The bike is getting noisy again, and I'm trying to work out if it's the hub or the motor - it's difficult to tell from up high on the saddle. It sounds like something like the chain is 'railing' but not sure what it is. I've checked the hub gears are adjusted correctly with the yellow markers, which they are.

I'm wondering what's causing the chain to go round and round while I'm not pedalling. I can't find the answer anywhere apart from one you tube video suggesting the hub gear is worn out.
 

Roger R

Pedelecer
Jul 6, 2015
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This is one of the videos I posted last year before the motor was replaced

Sent from my Nexus 9 using Tapatalk
 
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flecc

Member
Oct 25, 2006
46,172
22,896
Does anyone's chain keep going round when they are pedalling? I'm noticing it happen with my new motor, either it doesn't have much resistance itself or the hub gear is tightening up. I had noticed it now and again but confirmed my suspicion today when taking a rearward facing video. The bike is getting noisy again, and I'm trying to work out if it's the hub or the motor - it's difficult to tell from up high on the saddle. It sounds like something like the chain is 'railing' but not sure what it is. I've checked the hub gears are adjusted correctly with the yellow markers, which they are.

I'm wondering what's causing the chain to go round and round while I'm not pedalling. I can't find the answer anywhere apart from one you tube video suggesting the hub gear is worn out.
Sounds like the hub freewheel is binding, nothing to do with the motor unit.
.
 

RobF

Esteemed Pedelecer
Sep 22, 2012
4,732
2,308
The chain on my Rose/Bosch sometimes creeps forward on freewheel.

I reckon it's the Alfine 11 hub gear, not least because the creeping all but stopped after I changed the oil.
 
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