Ongoing reliability of Kalkhoff/Focus Impulse 2 motors

flecc

Member
Oct 25, 2006
50,646
28,489
has anyone ever tried to fix these engines, not for the "regular hobby-man) but more specialized craftsmen?
The problem with mechanical repairs is lack of any spares when the units have to sent back to get a new one.

When the Panasonic mid drive units were popular a few years ago that didn't have to happen, so parts from the odd failed units could be used to restore others and many were put back on the road that way, going on to last for years. In addition all the sealed bearings were standard easily available ones.

But with Bosch, Impulse etc., if a gear wheel shreds or other complex part fails, there's no viable solution other than a new motor.
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hannesd

Pedelecer
Nov 12, 2017
31
3
45
belgium
i didn't get an error display ...yet.
i'm not experiencing on/off jerky feeling.
as i said, my bike is like 80% ok so far...
if it would only not fade and start assisting after i stopped pedalling, then it would be a good bike for me...
it might be fixed with an upgrade, yes, i really hope so.
today i found the axle/spline where the front sprocket is located, moves aswell as the front sprocket.
front sprocket moving is ok ,i guess, but nog the axle with the splines moving in the engine?? it's minor but noticabe . no extra weird sounds yet...
 

hannesd

Pedelecer
Nov 12, 2017
31
3
45
belgium
The problem with mechanical repairs is lack of any spares when the units have to sent back to get a new one.

When the Panasonic mid drive units were popular a few years ago that didn't have to happen, so parts from the odd failed units could be used to restore others and many were put back on the road that way, going on to last for years. In addition all the sealed bearings were standard easily available ones.

But with Bosch, Impulse etc., if a gear wheel shreds or other complex part fails, there's no viable solution other than a new motor.
.
say i opened the engine up before catastrophic failure happens... and i could fit better bearings and what else needs fixing that can be found or made on a lathe?
 

flecc

Member
Oct 25, 2006
50,646
28,489
say i opened the engine up before catastrophic failure happens... and i could fit better bearings and what else needs fixing that can be found or made on a lathe?
I don't know the Impulse 2 unit well enough to say if anything can be easily made, but some of the parts that have caused problems can't be. For example the toothed nylon gear wheel and the pawl assembly. The quality of the bearings is unlikely to be a problem.

There are four photos of the pawl assembly components on this link
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Keterick

Finding my (electric) wheels
Oct 15, 2011
14
3
Is there an idiots guide to showing what software version is running?
When you press the off button, keep an eye on the display, it might flash up for about one second after the word "bye". I thought, from reading on this forum, that this was the software version, but mine still says C005, even though it's been updated, so I now have my doubts that it is the software version number. I will report back soon as to whether or not the update has made a difference to the actual ride.
 

hannesd

Pedelecer
Nov 12, 2017
31
3
45
belgium
I don't know the Impulse 2 unit well enough to say if anything can be easily made, but some of the parts that have caused problems can't be. For example the toothed nylon gear wheel and the pawl assembly. The quality of the bearings is unlikely to be a problem.

There are four photos of the pawl assembly components on this link
.
i did hear that the bearings are of questionable quality though...and because of lack of sufficient lubrication, these low grade bearings start wearing out...and in turn bring damage to the nylon gear wheel...
so maybe instead of grease, one could try the thickest oil available instead?
they opted for grease because ther's less chance for "leaks", oil will most likely start to leak the gaskets and seals.
 
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jimarno

Just Joined
Feb 5, 2017
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Barnsley South Yorkshire
The problem with my granddaughters low mileage 2013 model Agattu C8 impulse 1.0 step through bike ( 612 watt battery still shows 100% ) was a broken pawl in the freewheel drive in the crank .Kalkhoff will not supply replacement pawls despite these being wearing ,mechanical parts (easily and cheaply replaced as per any freewheel bike hub) and the motor out of warranty.50 cycles have quoted £600 for a new motor with a 2 year warranty.This is a very unsatisfactory state of affairs for any owner of these “”Rolls Royce “ of ebikes that are more than 2 years old
 

Jst_at_home

Pedelecer
Jul 8, 2014
36
13
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I've only just come back to this forum. 50 Cycles replaced the motor in my Tasman City 8 in the summer of 2016. Since then I've done over 1500 problem-free miles. I didn't have the "clacking" noise, mine showed "pedal" on the screen and assistance was intermittent. I have to say the the service I had from 50 Cycles was excellent and from Joe in particular. I saved the transit carton for "just in case" but it's looking like I won't need it.
 
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Nealh

Esteemed Pedelecer
Aug 7, 2014
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West Sx RH
I've only just come back to this forum. 50 Cycles replaced the motor in I saved the transit carton for "just in case" but it's looking like I won't need it.
:eek:Don't speak to soon, your now doomed keep the carton just in case.
 
The problem with my granddaughters low mileage 2013 model Agattu C8 impulse 1.0 step through bike ( 612 watt battery still shows 100% ) was a broken pawl in the freewheel drive in the crank .Kalkhoff will not supply replacement pawls despite these being wearing ,mechanical parts (easily and cheaply replaced as per any freewheel bike hub) and the motor out of warranty.50 cycles have quoted £600 for a new motor with a 2 year warranty.This is a very unsatisfactory state of affairs for any owner of these “”Rolls Royce “ of ebikes that are more than 2 years old
Surely its only a pawl? Kalkhoff won't have manufactured themselves a specific pawl. They'll have used something from a supplier that will be available and is probably used in hubs.

I bet if you take the pawl into a decent bike shop, one that's been around for years, so I'm afraid I'm talking about a shop that probably isn't an eBike shop.

Show them the pawl, tell them its from an unbranded hub. Can they find you one. I bet they'll have something.

Don't mention eBikes is the key to success here I'm sure.
 

flecc

Member
Oct 25, 2006
50,646
28,489
I bet if you take the pawl into a decent bike shop, one that's been around for years, so I'm afraid I'm talking about a shop that probably isn't an eBike shop.
Unfortunately they are these odd double ones with a shoulder. The one I'm showing is from a Panasonic unit, but the Daum is a copy, exactly the same design and may even be identical. But of course Panasonic don't supply spares either:

 
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Nealh

Esteemed Pedelecer
Aug 7, 2014
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The above pawl is the same as the ones in the Swizzbee rear hub. So might be a generic type.
I wondered if the 3/5 speed Sturmey's were a match but not quite.
 
Unfortunately they are these odd double ones with a shoulder. The one I'm showing is from a Panasonic unit, but the Daum is a copy, exactly the same design and may even be identical. But of course Panasonic don't supply spares either:

Yup, thats a totally generic pawl, that will be used by a host of hub brands.

eBike market is pretty small, so they won't be making specific parts they don't need to.

Many of the problems with eBikes are easily solved if you remove the e bit from the equation. They really aren't that complicated and bike shops have been solving them for close to 100 years in many cases.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
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grldtnr

Esteemed Pedelecer
Sep 22, 2012
627
287
south east Essex
Hmmm, sadly my impulse motor has failed, and I am reluctant to spend money on getting a replacement motor, if as KTM ( Colin ? ) states that it is a common part, I am minded to pull down the motor to replace the pawls.
The pedals freewheel , so I believe that the pawls are broken, you can try backpedaling untill the motor engages then you get drive, totally unfit to ride as you can't pull away.
Should I pull down the motor and not be able to source new pawls, will I be able to exchange the motor still with the German company that Sounded very posted earlier?
 
D

Deleted member 4366

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The German supplier can get you a replacement motor for about £400. They don't care if your motor has been disassembled.
 

Jst_at_home

Pedelecer
Jul 8, 2014
36
13
69
So, could anyone take a stab at answering the question "what's the best ebike to get"? I bought my Kalkhoff in the belief that it was a top brand and apart from the hitch with the new engine which 50 cycles sorted, it has been and continues to be OK.
 
D

Deleted member 4366

Guest
Wisper, Oxygen, Woosh, Juicy and Kudos. All have good support. All have components that you can buy from Aliexpress, so you're not at anybody's mercy. They're all relatively easy to fix by yourself. They're all good bikes. Oxygen MTB for speed and rougher cycle paths. Wisper Torque for it's super motor and torque, Woosh Karoo for lightness and price.
 
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Jst_at_home

Pedelecer
Jul 8, 2014
36
13
69
Wisper, Oxygen, Woosh, Juicy and Kudos. All have good support. All have components that you can buy from Aliexpress, so you're not at anybody's mercy. They're all relatively easy to fix by yourself. They're all good bikes. Oxygen MTB for speed and rougher cycle paths. Wisper Torque for it's super motor and torque, Woosh Karoo for lightness and price.
Thanks d8veh. Reason I ask us that I have a hankering for an e-MTB after I hired a Haibike in Austria in July. Nice bike but the chain snapped one day and tore the rear derailleur of its mounting but that's another story :)