Kenevo SL wobbly crank arm - repairable or not

[joshtammi]

So I went to go diagnose a pedal being a bit grindy today and realise my actual whole crank is loose on the drive side, such that it wobbles perpendicular to the rotational axis.

I thought maybe the crank came loose but it was tight to 50nm. So I removed it and found the actual bolt with the thread inside the crank is wobbly - is the fix as simple as just tightening that other part of the crank with the cassette tool to hold the bolt in place?

Unfortunately it’s one of the tools I don’t have so I can’t test it, plus it’s a Sunday here and LBS are all closed. I was hoping to go for a ride today

 

[joshtammi]

Will also add this video as after taking off the crank on the other side it seems that play in the bolt thread is normal.

 

[KnollyBro]

OMG... that is quite a lot of play in the crank arm! Did it happen suddenly or was it progressive? I hope the crank is not damaged.

 

[irie]

Will also add this video as after taking off the crank on the other side it seems that play is normal.

So the same play on both sides?

 

[joshtammi]

OMG... that is quite a lot of play in the crank arm! Did it happen suddenly or was it progressive? I hope the crank is not damaged.

To be honest, and I know this sounds absolutely crazy, but when riding the bike you actually can't really notice it. I got a mate to ride it and he said he couldn't notice it either. The only reason I noticed today was that I was taking out the pedal to clean out the dirt and noticed the whole crank moved.

 

[joshtammi]

So the same play on both sides?

Nope, it's only on the drive side in terms of actual play with the crank as seen in the second video. I originally thought the culprit was the bolt loose on the crank in the first place, but it appears from looking at the other side it is designed to be like that.

 

[squeegee]

I had this happen on a LSL but was because the crank wasn't tightened to 50NM for a period of time. The thing to be extra careful about is the spindle on the motor, it's alloy not steel so play like that will ruin the spindle as well. On my LSL they had to replace the motor and crank, since then I methodically torque the cranks to 50nm. Crank interface and/or spindle could be worn out, you could take the non drive crank and try to torque down on the drive side, if no play after switching then maybe just drive side crank is worn out. I kind of doubt the outer ring being loose is the issue because it's the groves on the crank and spindle that have to interface properly for no play.

 

[joshtammi]

I had this happen on a LSL but was because the crank wasn't tightened to 50NM for a period of time. The thing to be extra careful about is the spindle on the motor, it's alloy not steel so play like that will ruin the spindle as well. On my LSL they had to replace the motor and crank, since then I methodically torque the cranks to 50nm. Crank interface and/or spindle could be worn out, you could take the non drive crank and try to torque down on the drive side, if no play after switching then maybe just drive side crank is worn out. I kind of doubt the outer ring being loose is the issue because it's the groves on the crank and spindle that have to interface properly for no play.

Thanks,

I’ve got my bike booked in on Monday to have a look over it. I’ve only done about 600km on it since new, I just can’t imagine I’ve done that much wear to it already. It’s also been serviced twice in that period as well meaning it surely would have been picked up then and can’t have been loose for long.

Guess I’ll find out next week

 

[irie]

Thanks,

... It’s also been serviced twice in that period ...

Either not properly tightened, or not picked up, in a service. Not good.

 

[steve_sordy]

Deffo should not wobble like that. Warranty claim, either against the bike supplier or against the LBS that did the service. Maybe they are one and the same!

 

[squeegee]

Thanks,

I’ve got my bike booked in on Monday to have a look over it. I’ve only done about 600km on it since new, I just can’t imagine I’ve done that much wear to it already. It’s also been serviced twice in that period as well meaning it surely would have been picked up then and can’t have been loose for long.

Guess I’ll find out next week

If the bike is within warranty they will take care of it, all you have to do is insist upon that this happened and you don't know why. Could have not been tightened properly from the get-go and slowly came loose until the point it is now noticeable, and maybe too late to fix without replacing parts.

 

[joshtammi]

If the bike is within warranty they will take care of it, all you have to do is insist upon that this happened and you don't know why. Could have not been tightened properly from the get-go and slowly came loose until the point it is now noticeable, and maybe too late to fix without replacing parts.

Either way though, when I realised it was wobbly, I went to tighten it back to 50nm to find it already WAS tight to 50nm. That’s what doesn’t make sense to me.

 

[dumpy]

note that its normal for the "bolt" in the crank to be loose when off the bike. not normal for the crank to be loose on the bike. it can be several things (cant realy see it on the video), in order of what id consider likely:

- the aluminum sleeve is no longer bonding to the carbon (in my experience thats super hard to repair reliably because its missing carbon now though its possible, id just replace)

- the threads are dead (means it was lose or cross threaded f.e.). it might need a new spindle and crank if so

- the spindle/crank interface is bend - same story, spindle and crank swap

- spindle/motor interface is damaged, thats.. full motor swap if so

note that if its due to the last service not checking the torque id just swap bike shop or do it myself. i had several bike shops doing total crap, really good mechanics are rare because the pay is generally not great (but if you find one treat them well!)

 

[Myalteregohamish]

Thanks,

I’ve got my bike booked in on Monday to have a look over it. I’ve only done about 600km on it since new, I just can’t imagine I’ve done that much wear to it already. It’s also been serviced twice in that period as well meaning it surely would have been picked up then and can’t have been loose for long.

Guess I’ll find out next week

Hey Josh, @joshtammi you are 100% correct even though it's loose it won't come off. I just rode mine in the same condition after taking it off putting back on, cleaning, swapping cranks tried spacers. So here's the deal....

I let it get as bad as yours told my LBS what I tried and they put a ticket into Specialized. They came back and said, "Yes, there's a batch of specifically KSL's that have this problem. One of the machines was out of tollerance and produced out of spec drive side axles. Over time it creates play." I am waiting on a new motor now warrantied by Specialized. Since it's now my fourth motor in a year, I also asked if it is a new or refurbished one. They told me it's a brand new one, Specialized doesn't refurbish.

Andrew

 

[Rickster]

" Since it's now my fourth motor in a year, I also asked if it is a new or refurbished one. They told me it's a brand new one, Specialized doesn't refurbish."

Andrew

It's ONLY THE FOURTH Motor in a year !!
OMG , I would be selling that thing in a heartbeat. What happens when it's out of warranty ? Sorry but that's crazy

 

[steve_sordy]

Yep, there are too many stories like that for me to ever buy a Speccy.
People ramp up the Shimano motor hate, but I see nothing but Brose love.

 

[Myalteregohamish]

It's ONLY THE FOURTH Motor in a year !!
OMG , I would be selling that thing in a heartbeat. What happens when it's out of warranty ? Sorry but that's crazy

100%.

Crank issue I gave up on it for a few months. I ordered a CEF50 with a Bafang M820 from a factory in China but the build times were still a few months from delivery to the states. It was an experimental bike to see if I could build a bike as good as a KSL at a fraction of the cost (the answer is yes btw). I wanted to have an eMTB frame only option so I can take advantage of all these components I've been accruing. This was supposed be a back up bike for when the KSL was in the shop. At the same time I wasn't so sure about the Bafang so I bought a Canyon Torque:ON and was going to sell the KSL. Torque:ON is an amazing bike as a side note. However, when I went to sell the KSL there were hundreds of KSL's and Levo SL''s for sale. So now I've decided I'm stripping the bike fdown to a KSL frame only with two range extenders and selling that. I didn't see anyone just selling the frame out there. I figure I'll get 1500 for it'

 

[squeegee]

It's ONLY THE FOURTH Motor in a year !!
OMG , I would be selling that thing in a heartbeat. What happens when it's out of warranty ? Sorry but that's crazy

On the other hand you could have a 1.1 motor like I do on a LSL, 4 years old and 5500 miles and still working well. It's a buyer's market right now so selling used means a significant loss. Warranty is only 2 years so unless you are in the habit of buying/selling eventually you might have to deal with out-of-warranty expenses. Ebikes are expensive to buy and maintain, it just goes with the territory, got to pay to play.

 

[irie]

It's ONLY THE FOURTH Motor in a year !!
OMG , I would be selling that thing in a heartbeat. What happens when it's out of warranty ? Sorry but that's crazy

Speechless!

 

[Myalteregohamish]

On the other hand you could have a 1.1 motor like I do on a LSL, 4 years old and 5500 miles and still working well. It's a buyer's market right now so selling used means a significant loss. Warranty is only 2 years so unless you are in the habit of buying/selling eventually you might have to deal with out-of-warranty expenses. Ebikes are expensive to buy and maintain, it just goes with the territory, got to pay to play.

I don't like it but I know you're right.

 

[joshtammi]

It's ONLY THE FOURTH Motor in a year !!
OMG , I would be selling that thing in a heartbeat. What happens when it's out of warranty ? Sorry but that's crazy

That or i'd be asking for a free upgrade to the 1.2 haha

 

[TG1971]

Mine had same issue after 500 miles even though fully tightened, lbs put a new crank and still wobbled, lbs had to replace the motor and new cranks.

 

[Myalteregohamish]

Mine had same issue after 500 miles even though fully tightened, lbs put a new crank and still wobbled, lbs had to replace the motor and new cranks.

Just got mine back from the bike shop yesterday. Fourth new motor no wobbly crank arm, we’ll see how it goes.

 

[TG1971]

Just got mine back from the bike shop yesterday. Fourth new motor no wobbly crank arm, we’ll see how it goes.

Pretty shit design if you ask me

 

[Myalteregohamish]

Pretty shit design if you ask me

You’re not wrong.

 

[joshtammi]

Wait, so to confirm, you have had 4 x motor swaps for wobbly crank arm? or different issues?

Cheers!

Just got mine back from the bike shop yesterday. Fourth new motor no wobbly crank arm, we’ll see how it goes

 

[Myalteregohamish]

Wait, so to confirm, you have had 4 x motor swaps for wobbly crank arm? or different issues?

Cheers!

Different issues:
- torque sensor failed
- made a grinding noise that kept getting worse
- gear wouldn’t engage
- wobbly crank

 

[joshtammi]

Different issues:
- torque sensor failed
- made a grinding noise that kept getting worse
- gear wouldn’t engage
- wobbly crank

Yep ok. Damn unlucky either way though.

I dropped mine off to the shop on Saturday. Waiting on response from Specialized. In the meantime, I’ve ordered a Trek Rail

 

[Myalteregohamish]

Yep ok. Damn unlucky either way though.

I dropped mine off to the shop on Saturday. Waiting on response from Specialized. In the meantime, I’ve ordered a Trek Rail

After the second time the motor had to be warrantied, I start scouring the DIY part of this forum for a frame only option as a backup bike. It seems par for the course that whatever EMTB you end up with at some point you might be out a bike for a few weeks.

 

[joshtammi]

Update today:

Motor and cranks to be replaced (TCU as well as the screen has an LCD leak). Only issue - no spare motors in the country and no ETA to when it will be fixed.

Thanks all