Sprag Clutch failure (Updated title) and how common is it?

TheBikePilot

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Oct 9, 2018
928
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Clapham, London
I think with all the failures and PR they will extend the warranty on the Motor if you have had a new one fitted, but that's not gospel truth.

They deal with everything on a case by case basis.
 

ReinerSt0ff77

Member
Jan 15, 2020
36
46
weedfield
Sounds like my Motor was also a Sprag failure,i know it before i buy one,thx to Bearingman.
But i am waiting for a part from Haibike since September.
Do i need 3 Ebikes,1 will running maybe :rolleyes:
 

wepn

The Barking Owl ?
Jul 18, 2019
1,006
1,145
AU
My 8 month old Kenevo is fine but I have the expectation that a high end expensive bike will last years beyond the warranty and with battery replacement, years after that. Am I delusional?

I have an 11 year old bush bashing hub motored power monster that has done over 100,000 km. With another new battery & other expected replaceables, it'll last another decade. I have a feeling that Specialized may not still be producing spare parts for 10 year old bikes. So it seems I am - more than likely - delusional.
 

Levo Laland

Well-known member
Nov 27, 2019
273
236
Surrey UK
Berkshire Cycles have replaced over 100 motors in the last 3 months, but Chris says he’s getting people travelling from all over the country to get him to replace them.
 

Matt Seabrook

Member
Jun 9, 2018
62
47
St Austell Cornwall
It depends where you take it and if they have exchange motors in stock.

Long, but worth a watch ..

I’m just trying to get an idea of the current stat of affaires to be honest. I have been having these type of issues with my bike and am just curious as to what is reasonable to expect. I messaged rider care back in the middle of April about the problem I was having as my LBS was closed due to the Covid issues. My bike is a 2018 so coming to the end of its guarantee and not knowing when my bike shop would reopen thought is wise. I had email messages going back and forth and they said the bike needed to go in to a store to be looked at. This is perfectly reasonable and they even looked at getting it booked in for me. In the mean time my LBS and where I brought the bike from reopened. Rider care told me I had a choice of two places to take it and I chose to take it back to the place I brought it from. I popped down to the shop and booked it in to be looked at two weeks later. Now this wasn’t a massive problem as the bike was still rideable if a little unpredictable at times. So on the 23rd of May I took my bike in with all the details of the fault and giving the LBS the claim log number from Rider Care. After a week I rang the shop to find out if there was any news or just an update on the problem. The chap on the phone was less then helpful and I felt I was an inconvenience for phoning. Now I know that at present they are working under difficult conditions due to the way things are at the moment , but I only wanted an update and possible eta if they knew one. So another week goes by and rather than get poor service from the bike shop I thought I would contact ride care on the 7th of June. Rider Care got back to my email within a couple of hours. They told me that the mix up had been who was raising the warranty claim and it would be sorted and parts are now being sorted and they had been in touch with the store. So far I still haven’t heard from the store about a time frame as to when my bike will be going in to the workshop so I was just looking to see other peoples experiences of how long this takes else where.
 

Viper9559

New Member
Apr 14, 2020
13
2
Monterey, CA
Why would Brose even try? As far as they are concerned this part is fully fit for purpose. It was in the 1.2, 1.3 and now the latest 2.1 motors.
Brose are happy that in 99% of the bikes this motor is fitted into, it works fine! They would not listen to Specialized any more than they would listen to you or me. If it's a 1% or less failure rate out in the world then that's acceptable.
Remember, there is a big world outside of EMTB's. There are commuter bikes, shopping bikes, cargo bikes etc. And in Europe they outnumber mountain bikes 100/1. So when you factor all this in, Brose failure rate is probably closer to 0.01% with many, many happy customers.
Frustrating though isn't it.
Good points...
 

jsharpe

Active member
May 15, 2019
181
185
USA
After watching the video and hearing that many/most belt failures are actually the clutch ring breaking it got me thinking. Could maximum rider input relate to the failure rate?

Some people have had many failures while others have had none. Are the folks that have failure after failure particularly strong riders and putting lots more energy into the clutch? That would seem to me to be more plausible that some people being repeatedly really unlucky. I have recorded every single ride my bike has done with Blevo and just went back and looked through a bunch of the rides that I remembered working particularly hard. No laughing because I'm an old fart riding at relatively high elevation, but a typical value for me for "Maximum Rider Power" as recorded by Blevo is 470w. I did have one ride that basically went straight up a steep snow-covered ski slope where I completely maxed out both me and available traction for a hundred yards or so and that rated a max rider power of 575w. I can easily hypothesize that someone consistently mashing 600 or more watts into the clutch might have more chance of a failure than the weaker riders like myself that don't/can't ride that hard.
 

Murch

Active member
Aug 9, 2019
222
185
United States
I think it is a factor as I have seen 1100 watts of rider input and regularly have readings in the 700s. I have also seen the failure on a bike where I doubt, she ever was near 500 watts.
 

TheBikePilot

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Patreon
Author
Oct 9, 2018
928
905
Clapham, London
Also other factors such as pedal strikes, crashes that could put way more than 1100w temporarily through the clutch.

There doesn’t appear to be a trend that’s been identified.
 

jsharpe

Active member
May 15, 2019
181
185
USA
Also other factors such as pedal strikes, crashes that could put way more than 1100w temporarily through the clutch.

There doesn’t appear to be a trend that’s been identified.

Ahhh, good point. I hadn't thought about that.

Has anyone heard if there is any change to the clutch in the updated (build date > Jan 2020) version of the motor? I'd only read something about a kevlar reinforcement to the belt.
 

Bearing Man

Ebike Motor Centre
Patreon
Sep 29, 2018
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UK
Ahhh, good point. I hadn't thought about that.

Has anyone heard if there is any change to the clutch in the updated (build date > Jan 2020) version of the motor? I'd only read something about a kevlar reinforcement to the belt.
I have done posts before regards pedal strikes. This is a major contributor i believe, but not the only reason. There is no change to the clutch and I believe the belt is still carbon but a few more strands thicker.
 

Troutwrestler

Member
Dec 25, 2018
136
88
Scotland
I think my 3rd motor is now starting to do the over-run thing just like the last 2. It is definitely NOT cutting out in 0.2 seconds. I can feel and hear the over-run, especially when I am pedalling uphill and stop pedalling for a second to clear an obstacle. Tonight I rode the Innerleithen Red XC trail, and on the rock-studded second section of the climb it was noticeable - especially as some of the rocks are pretty slippery/polished and don't tolerate any power delivery, human or motor, when riding up and over them.

At this point if I take the bike to the shop they are going to think I am bonkers. I guess I need to keep riding until it gets so bad is is clearly apparent. Maybe a go-pro mounted on the down tube will capture it happening, and I could get a measure of the time it takes to cut out too.
 

DS.

Member
Mar 15, 2019
90
61
Devon
Yeah mine keeps going when you get of the bike just goes on it’s own sometimes I got to pull power lead of to stop it had a new lead recently but it still does it.its worse when your climbing and then stop and there’s a lot of power going though the motor the bike just wants to shoot of I like the Levo and hate moaning about it but it’s got it’s issues
 

STK

Member
Apr 23, 2019
34
15
San Diego
When these sprag bearing start to go they can slip and grip. This slipping and gripping action is actually very violent for the bearing itself. It causes the small spacers in between the sprags to break off and eventually flip over and become useless, this eventually leads to slipping or complete failure.
2019 Kenevo expert with 3300 miles developed these symptoms today and it really helped me understand that it wasn’t the belt breaking, which was the main issue I had heard of. Looking into this it seems the clutch is much more common. I took it back to the shop and it looks like they will warranty the motor. I hope to get it back in a few weeks and that the new motor goes at least another 3300+++ It only takes a few acoustic rides to remind me of how much I LOVE this bike. Thanks.
 

Taffyteg

Active member
Founding Member
Feb 13, 2018
201
129
United Kingdom
It's a bit of a major operation to change one of these bearings, the crank one is easier than the pulley one, but both require a few special tools etc. Take a look at my video, you will see the bearings in question.
Great video - many thanks for putting this together. Do you recommend servicing the motors every year or 2 or basically wait until something starts to feel wrong and then look at getting it serviced?
 

Bearing Man

Ebike Motor Centre
Patreon
Sep 29, 2018
975
2,331
UK
Great video - many thanks for putting this together. Do you recommend servicing the motors every year or 2 or basically wait until something starts to feel wrong and then look at getting it serviced?
No service should be necessary apart from a belt every 15,000 Km. The best thing you can do is every month or so, drop the chain of the front sprocket or chainring and turn the cranks by hand. The cranks should turn smooth, free and quiet. Anything else should be checked out. Most issues, if caught early are a relatively cheap fix, once the crank is stiff to turn backwards or can be heard or felt when turned forward, it's already costing you more money!
 

Mind

Member
Oct 12, 2022
13
11
France
Had a very distinct "clac" (metal on metal) noise each time i stopped pedaling, 90% sure it was a sprag bearing issue.

Engine replaced under warranty, fixed the issue. (Gen3 Levo Comp Carbon)

 
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