Levo Gen 2 Turbo Levo won't roll backwards

[Boracho Muchacho]

I wondered about the rough terrain. I have another thread here about switching to a coil shock because there is so much washboard hard pack on my regular trail. Some of it is in high speed sections that must be rough on the bike.

Edit: I'm in the US, and I've learned to stay below the ~20 mph motor cutoff on the flats. I don't think I've had excessive engage/disengage cycles.

There is something inherently wrong about having to worry that you will damage a mountain bike by riding it over rough terrain....

 

[Rosemount]

Sadly it’s not all pedal strikes, many people we talk to have never suffered a strike or even fallen off. The bearing does just wear and fail in normal use too. High temp won’t hurt the bearing, or low cadence high torque, these are more belt killers. But shock does seem to hasten a bearings demise. I suspect this could also be caused by rough terrain, poor gear changes under load etc. We tend to see crank sprag bearing failure from hard riders and motor pulley sprag failure from more gentle road riders that keep the motor around its restricted cutout limit. Each time you go above 15.5mph the motor cuts for example, then when you drop below this speed the motor kicks in and momentarily has to catch up with the other moving parts, this could put constant small shock loads through the bearing? Just another theory we are working on.

I dunno TBM ?
Never had an off ? And never a peddle strike ? Sounds like @Gary !! lol . Or are they telling you fibs ?

 

[Zimmerframe]

Never had an off ? And never a peddle strike ?

We might have to add stabilisers to the top 10 causes of motor failures ...

 

[RebornRider]

There is another way to expose the motor sprag bearing fault. Riding the bike with the power off I could feel motor drag coming and going. Sometimes I could ride 10 meters with the bike feeling like a normal (but very heavy) analog bike, then the feel would change abruptly as if I was squeezing the brake levers. There would be heavy drag for a few pedal rotations, then the drag would disappear for a few rotations. "Wash. Rinse. Repeat." This may be enough of a symptom for my bike shop to do a warranty repair.

@Bearing Man What are the common terms for the two Brose sprag bearings? I want to avoid confusion when talking about this problem.

 

[Bearing Man]

There is another way to expose the motor sprag bearing fault. Riding the bike with the power off I could feel motor drag coming and going. Sometimes I could ride 10 meters with the bike feeling like a normal (but very heavy) analog bike, then the feel would change abruptly as if I was squeezing the brake levers. There would be heavy drag for a few pedal rotations, then the drag would disappear for a few rotations. "Wash. Rinse. Repeat." This may be enough of a symptom for my bike shop to do a warranty repair.

@Bearing Man What are the common terms for the two Brose sprag bearings? I want to avoid confusion when talking about this problem.

I just call them the 'crankshaft sprag clutch bearing' and the 'large drive pulley sprag clutch bearing'.

 

[Mikerb]

Interesting hypothesis .........it suggests a sprung loaded friction type clutch would make more sense there than a sprag bearing. Taking it a bit further............The software requires there to be crank torque before the motor provides any pedal assist, so the bike exceeding, then dropping below the speed cut off will not cause the motor to operate unless there is torque on the cranks............and if there is torque on the cranks the "shock" of sprag bearing engagement on the big pulley wheel will presumably be least if the mode being used is ECO and (on a Levo) acceleration is set to zero.

 

[Grannyjones]

Mine was like this a couple of weeks ago after I used it as a submarine.

If you get any moisture in there from submersion, jet wash and so on it will rapidly increase the chance of sprag clutch failure.

Fortunately (for now) .. mine's fixed itself ..

I rode through a long hub deep puddle that went on for ages.
The motor area was submerged.
I never expected the puddle to be so deep, I felt proper stressed when the bike went under.
Luckily no ill effects, even 2 weeks later.
The puddle was near the beach as well, so likely to be salty water rather than fresh water.

 

[Bearing Man]

Interesting hypothesis .........it suggests a sprung loaded friction type clutch would make more sense there than a sprag bearing. Taking it a bit further............The software requires there to be crank torque before the motor provides any pedal assist, so the bike exceeding, then dropping below the speed cut off will not cause the motor to operate unless there is torque on the cranks............and if there is torque on the cranks the "shock" of sprag bearing engagement on the big pulley wheel will presumably be least if the mode being used is ECO and (on a Levo) acceleration is set to zero.

Unfortunately, “sprag clutch bearing” is not really an accurate description of this bearing. The more accurate description is ‘backstop bearing’ it is a bearing usually used to stop a machine turning or rolling backwards once stopped.
Possibly a ramped needle roller type clutch bearing as used by Yamaha or Bosch may have been the way to go?
Most motors apply their power in a relatively linear way. Brose motors tend to apply most torque on initial take off so the motor feels strong and torquey, so yes...soft or low power delivery would be better for the motor but not much fun ?

 

[Bearing Man]

I rode through a long hub deep puddle that went on for ages.
The motor area was submerged.
I never expected the puddle to be so deep, I felt proper stressed when the bike went under.
Luckily no ill effects, even 2 weeks later.
The puddle was near the beach as well, so likely to be salty water rather than fresh water.

I will book you a slot in the workshop ??

 

[Grannyjones]

I will book you a slot in the workshop ??

I know for a fact the chain didn't like it - made an awful sandy grinding noise for the rest of the ride and very soon after it stretched to 0.5 and had to be thrown away! (after only being on for a total of 172 miles)

No ill effects noted elsewhere on the bike though

 

[jbodnar]

I heard funny grinding noises while pedaling/shifting today on my 2020 Comp and I felt a lot of resistance suddenly on the pedals riding a slight uphill in trail mode.

Initially I thought my derailluer got mangled some how, but it was fine.

I immediately stopped and got off the bike...the rear wheel wouldn’t go backwards...it still won’t go backwards.

I pushed it uphill until I could ride down and walk it to my truck.

I only have about 710 miles on it...this is my first failure.

Seems like the cranks will turn forward now without as much resistance with the motor on...the rear wheel still won’t roll backwards (knock on wood).

I sure would love a 2.2 replacement motor, but I guess warranty beggars can’t be choosers...it‘s back to the LBS tomorrow.

I think I’ll refrain from further testing...I took off the chain just to make sure the rear wheel spins backwards freely.

I’m lucky to have a 2021 SL Carbon Comp as my “backup” ebike.

 

[RebornRider]

My "won't roll backwards" symptom has disappeared. I haven't done anything different or anything to fix it.

 

[Bearing Man]

My "won't roll backwards" symptom has disappeared. I haven't done anything different or anything to fix it.

This is quite common, a crank stuck by a jammed sprag or rusted bearing can be freed by a slight knock or even a change in temperature. However, it is a big warning sign that something is failing.

 

[jbodnar]

My "won't roll backwards" symptom has disappeared. I haven't done anything different or anything to fix it.

Today mine is rolling backwards, but you can feel and hear that something is wrong (feels/sounds like the belt slips when pedaling).

Coincidentally, I had stopped into the LBS last Thursday and asked if they ever have to replace the belt on the motor...he said they “only replace the motor, they don’t open it up”

Forgot it is Easter, so the LBS is closed until Tuesday.

 

[jbodnar]

Today mine is rolling backwards, but you can feel and hear that something is wrong (feels/sounds like the belt slips when pedaling).

Coincidentally, I had stopped into the LBS last Thursday and asked if they ever have to replace the belt on the motor...he said they “only replace the motor, they don’t open it up”

Forgot it is Easter, so the LBS is closed until Tuesday.

I’m getting a new motor (warranty) maybe next week...I wish it would be a 2.2 version...but I’m expecting the updated 2.1.

 

[salko]

How would you even distinguish v2.1 from v2.2?

 

[urastus]

We know about yours And the intrinsic problems. You also forgot to mention the software issue on the 2.1's which caused micro pulses which put additional strain on the sprag/belt - hence the warranty extension on those bikes (and yet still the flat earthers refuse to upgrade their firmware and will then complain when their motor fails).

Yes, water is a motor killer. Get that inside and things start to rust up and kaboom - your motor's shot. Better sealing and stronger sprag bearings would be the dream, and fortunately for us Bearing man makes the dream a reality. Maybe you could argue the motor should be like that as standard, but you could still upgrade your motor with Bearing man without waiting for a fail if you wanted to. Just as some people will extend the breathers and fit a snorkel to their vehicle rather than drowning their engine.

There's a whole host of reasons why. Some people are just unlucky. Some people jet wash and don't care. Some people ride through deep water and pretend it never happened.

The ones that are interesting are the 3/4/5 motor people. The majority of people have no failures, yet some have multiple.

Is this due to the dynamics of how they ride which is somehow incompatible with the way the sprag works ?

Do they have more pedal strikes, or some other form of impact, either because of where or how they ride ?

Is it how they transport their bikes ?

Is it something to do with how they wash it ? Is the motor warm and the air in the motor warm so as it cools with washing, the air contracts creating negative pressure and actually drawing water in ?

Is the bike so loved, it's washed in the bath ?

I'm not saying any of these are what happens, or that any of these people purposefully abuse their bikes or are negligent, but there must be some pattern which is different for multiple motor failure people than for others. It would just be interesting to try to work out what that might be.

If you knew, you could try to avoid what causes the problem. I doubt anyone wants a failed motor.

It's really sounding like poor reliability. Is it up to us, as the customers, to try and figure out why these failures occur if we're riding and using them as mountain bikes? Although, I still don't understand the current trend of washing bikes. That is a relatively recent backward step that defies logic . I do clean bikes, but no hoses involved and minimal water; wipe down with mild solution of wash n wax. Rinse out regularly. Always use brushes to get dried mud etc off first.

 

[urastus]

OP here. What do you think is going wrong inside my motor case given these symptoms:

• Bike pedals and coasts normally
• Motor does not make unusual noises while riding
• Sometimes it is *very* hard to push the bike backwards (which turns the chainring)
• Sometimes there is noticeable resistance to the backwards push, but it's not super hard to push
• Most of the times when I check, the bike pushes backwards with no resistance (e.g. at my lbs)
• When the problem occurs, pushing the bike backwards causes a "shhhh" noise from the motor
• Crank clutch spins freely (back pedaling)
• Problem happens with the battery connected and with the battery disconnected

I'd try to figure out where the problem is first. EG, rule out the wheels. When it doesn't want to go backward, lift up the rear end and try spinning the rear wheel in a backwards direction. Do the same for the front. It could be the gear skipping thing that happens if you're in a high gear - wheeling backwards causes the chain and derailler to try and move to lower gears; it's a big mess . You end up with a chain across several gears, which is a bit of a hindrance if you're trying to wheel backwards

 

[urastus]

My "won't roll backwards" symptom has disappeared. I haven't done anything different or anything to fix it.

what gear were you in when it rolled backwards successfully? What gear were you in when it didn't?

 

[jbodnar]

How would you even distinguish v2.1 from v2.2?

I assume if it has the newer covering over the charging port, it‘ll be a 2.2, otherwise it will be an updated 2.1.

Read in a post somewhere that diagnostics shows the motor serial number which also contains the motor manufacture date...not sure about the date for the updated 2.1 motors.

 

[salko]

I assume if it has the newer covering over the charging port, it be a 2.2, otherwise it will be an updated 2.1.

Read in a post somewhere that diagnostics show the motor serial number which also contains the motor manufacture date...not sure about the date for the updated 2.1 motors.

Charging port is not part of the motor but part of the battery harness. I'm pretty sure the new motor has same ports (for TCU, speed sensor, battery, lights etc.), just harness to the battery port is new/different ...
Yes, the motor serial contains manufacturing date, but since Spesh/Brose does not give out exact dates when the motor was updated I'm sure it will not be so obvious ...

 

[Zimmerframe]

I wonder if @Rob Rides EMTB / @Citylad77 / @Austin Thomas could share a Mission Control screen shot of theirs on the motor page ?!? It might give some indications towards identifying 2.2's in future ?

 

[congerball]

I assume if it has the newer covering over the charging port, it‘ll be a 2.2, otherwise it will be an updated 2.1.

Read in a post somewhere that diagnostics shows the motor serial number which also contains the motor manufacture date...not sure about the date for the updated 2.1 motors.

I had a new 2.1 motor fitted recently, it has a manufacturing date of 31/08/20....When I asked if the new motor will have the ‘upgrades’ I was told yes by Specialized....I’ve recently been told that it will only have the upgraded belt ?‍

It feels smoother and is quieter so I’m happy.

 

[Austin Thomas]

I wonder if @Rob Rides EMTB / @Citylad77 / @Austin Thomas could share a Mission Control screen shot of theirs on the motor page ?!? It might give some indications towards identifying 2.2's in future ?

Always happy to help...
and can I just say the GEN3 bike is Soooooooooo much fun to ride. That is all.

 

[Zimmerframe]

Always happy to help...

Thanks Austin ! That's going to confuse everyone

Glad to hear you're enjoying the bike !!! It looks like a fun beasty !!!

 

[Austin Thomas]

Thanks Austin ! That's going to confuse everyone

Glad to hear you're enjoying the bike !!! It looks like a fun beasty !!!

Oops sorry. Don’t want to alter the culture if that is not wanted...
PS. This bike defines the word FUN. Especially for an old bloke like me trying to hold on to my youth...

 

[Zimmerframe]

Oops sorry. Don’t want to alter the culture if that is not wanted...

LOL .. no , it's the dates which will confuse everyone .. so now trying to work out how you differentiate the 2.2 from the 2.1

 

[Zimmerframe]

So some older ones which I think had the previous belt upgrades :

Maybe the "2" after the date numbers and before the last 4 digits ? (or two digits on Austin's) .. I'm only grasping at straws though - it might be something only Spesh can identify purely on how they have them logged and which ones they know had the 2.2 upgrades.

 

[SwissChess]

Maybe the "2" after the date numbers and before the last 4 digits ? (or two digits on Austin's) .. I'm only grasping at straws though - it might be something only Spesh can identify purely on how they have them logged and which ones they know had the 2.2 upgrades.
[/QUOTE]

or 2.2 is just marketing

my last broken motor was E0168-100200622-2-5130 I was told it had a upgraded one ? let's see what I will get for a new one

 

[Bearing Man]

How would you even distinguish v2.1 from v2.2?

The clue was actually in Robs video...Listen from 21:30