Levo Gen 2 Crack when first cycling off

[Snrbrtsn]

21 Levo, new motor circa 900kms ago back in April
When I first cycle off, there’s a crack, during cycling no noise, what’s the chance of it being chain ring / chain as opposed to motor ?

New chain & cassette around the same time as motor swap
Last night I backed off all motor bolts and torqued circa 18Nm backed off the motor guards bolts and tightened, removed the lower pivot bolt, cleaned under chain stay at motor foam pad, yet today it’s still cracking whether on or off seat
Checked chain wear albeit, not with a 12 speed chain checker and it’s a very tight squeeze to 0.75
Chain is wiped & lubed after most rides with Squirt dry wax…
No notable wear on chain ring

New chain time or ……

 

[Mikerb]

On my 2019 Levo the chainring needed to be changed when I fitted a new cassette and chain. When you start off that is when you are most likely to exert maximum torque on the drivetrain. I did not have the "crack" noise you describe but I could both hear and feel that the chain was running rough on the chainwheel.

 

[muzzman1]

I would think motor bolts. I believe spec is 20Nm, but 18 is close enough. I've had my rear two motor bolts, (under the chain stay) come loose and experienced the "crack" you describe.

 

[Snrbrtsn]

Many thanks for response!

I took the motor bolt torque from the manual 18.3Nm, no harm in nipping up to 20Nm
I was trying to age the chain ring and failed, can find every other receipt, probably circa 3500k on the chain ring so likely due a change,
I do have the original smaller chain ring, may try that tomorrow with a new chain

I was thinking about max torque when setting off and that has me thinking is it sprag clutch in the motor though I’m honestly unsure of the workings

 

[RebornRider]

Remote diagnosing is suboptimal, but I will say that I finally fixed a loud creaking in my Levo by replacing all of the motor mount bolts. Not saying you need new parts - it may be that my removal of the motor and then carefully reinstalling it was a big part of banishing the creak. Also, FWIW, I put bearing grease everywhere mechanical parts touched.

 

[Snrbrtsn]

Ooo Poop!
The motor bolts under chain stay - I don’t think I checked…. Though must have! but only recall torquing 4 bolts + the chain stay bolt as I had pulled the bearing covers to check bearings and clean out the top of motor behind chain stay - even with sitcomb guards it’s pretty gritty there!

 

[Snrbrtsn]

Remote diagnosing is suboptimal, but I will say that I finally fixed a loud creaking in my Levo by replacing all of the motor mount bolts. Not saying you need new parts - it may be that my removal of the motor and then carefully reinstalling it was a big part of banishing the creak. Also, FWIW, I put bearing grease everywhere mechanical parts touched.

Absolutely agree!

Ill be checking missing bolts in morning - I’m prone to using more than my share of white assembly grease and Red Bearing grease on all parts too! Though I’m careful to clean the threads after to avoid grease lock or over torquing lubed threads

 

[Snrbrtsn]

I would think motor bolts. I believe spec is 20Nm, but 18 is close enough. I've had my rear two motor bolts, (under the chain stay) come loose and experienced the "crack" you describe.

Are they accessed by removing motor covers ?

 

[RustyIron]

I’m prone to using more than my share of white assembly grease and Red Bearing grease on all parts too!

Good on ya. I was going to suggest putting grease on everything before it's assembled. You might need to look beyond the motor: cranks, pedals, seatpost, pivots, etc.

 

[Snrbrtsn]

Bike having the full strip down
I did not check the back motor bolts - knowing primarily as chainring restricts access to drive side. so I shall drop the shock pressure & remove to gain access

Dont see much notable wear on the chain ring ? I’ve cleaned the cassette in Prep for new chain

 

[Snrbrtsn]

Well after the strip down and ride I’m all smiles

Fork was pulled headset cleaned greased and refit
Seat & Seat post striped cleaned greased and refit
Crank arms pulled cleaned regressed and refit
Chain removed
Chain ring removed, cleaned & inspected and refit
Battery removed bash plate cleaned & refit
All motor bolts (x6) removed & cleaned taper bushings greased and refit
Motor cover bolts removed cleaned and refit
Wheels removed, cassette and discs cleaned and refit
Derailleur striped, jockey wheels cleaned, greased and refit
Rear shock pressured and balanced
New chain degreased cut to size and fitted

Attempts made to install OEM chainring as little use, however chain length with 36t chainrings permitted fitment without losing a couple of links so old unit cleaned and refit
Gear index checked - All good!

”All” mounting bolts torqued per manual spec
In doing the above I trashed my torque wrench trying to back off pedals, so that was striped and pawls switched over to allow interim use and bike refit.
Tyres inflated for Road

Took bike for a mixed 40k ride, Firetrack, road & trail with frequent stops to pull away in different gear and modes, came home all smiles, noting soft compound tyres dont half bite the tarmac

I’m inclined to say, it was the chain albeit with little wear, however, per muzzman1 post (Thank you!) I’m thinking it was the lower motor bolt hidden behind the chainring, both sides were torque checked before removal, drive side was found slightly loose, needing a pull and a bit to reach full torque

I’m overly relieved either way, whilst I highly rate the supplying bike shop for their service and prompt action during last motor change, I didn’t want to trouble as my service needs are mainly DIY….
My motor lives on and pulls very well, enlight of this frustration, I’ll revert to new chain every 7/800k and torque motor bolts more often (probably bi weekly)
Must remember to get a new Torque wrench as I can now only tighten torque!

Thank you muzzman1 for pointer!