Chain came off: Vado SL 4

[Abridged]

I had to change my chain (and break pads) after about 1500 miles. I was very embarrassed as my bike tech knowledge is pretty rubbish. The guy at the bike social enterprise asked me how did I not notice that my brake pads had no actual pads on them left?!

 

[Stefan Mikes]

I suspect that most folks with more typical "e-bikes" would be astonished to hear that a chain could last 7000 miles on a Vado SL.
I check my chain stretch about every 90 days +/- and have seen no obvious wear whatsoever to this point.

Riding mostly OFF?

 

[Stefan Mikes]

I had to change my chain (and break pads) after about 1500 miles. I was very embarrassed as my bike tech knowledge is pretty rubbish. The guy at the bike social enterprise asked me how did I not notice that my brake pads had no actual pads on them left?!

You need to replace brake pads if you live in a hilly area. The chain stretch at 1500 miles is a normal thing.

I have about 7000 miles on the bike before I changed the chain, chain ring and cassette.

The 7000 miles has ruined the whole drivetrain I prefer replacing the chain after it's stretched at 0.75% max. I use higher assistance modes on my Vado SL (ECO = 60/60%)

 

[mfgrep]

Riding mostly OFF?

I would say that the motor is off > 50% of the time yes.
I would also say that I am a 'careful shifter' and am mindful to shift 'properly' and without adding unnecessary torque to the drivetrain.
Of course I am not perfect....but I do naturally attempt to shift as cleanly as possible at all times. Careful shifting, I believe, is of particular importance to the drivetrain on bikes that have electric motors

 

[Jeremy McCreary]

Of course I am not perfect.

Why not? My wife's first husband was.
;^}

 

[BioWheel]

If I had to criticize my VadoSL in any way - it would be chain drop. I replace my chain about every 1500 miles and have changed the rear cassette twice and the front chain ring once in the bikes lifetime (about 12000m). And chain drop can still be an issue if I'm on bumpy terrain and unable to keep pedaling (like coming down steep drop and maneuvering). And drops are even more likely when doing lite mtb. I would say a newer chain drops less but never really had any luck with new rings having any positive affect. Anyway, if Specy could just put a chain guard on (like my LevoSL) it would be perfect. And - would be nice to have another mil or two between chain ring and frame so it doesn't take prying to get the chain out.

 

[PedalUma]

A guy last week got mad at me. More about that in a second. Any bike that hits the precise intensity and frequency of bumps will make a wave like a whip through the chain and it will drop. Okay, so this guy had a chain drop. The chain was stretched and the cassette worn, due to lugging the motor and not downshifting, also he lost his main motor mount and the motor distance from the rear axle was flopping. I fixed all those things that needed fixing. Then his chain dropped again on a Mount Tam decent while coasting. What he really needed in addition was a mountain grade derailleur with a strong clutch. He had a road grade derailleur on a mountain bike.

 

[Stefan Mikes]

I wonder whether it is any difference between Shimano and SRAM drivetrains related to the phenomenon of the chain dropping.
SRAM has no derailleur clutch, Shimano has the Shadow+. The clutch keeps the chain tensioned at all the times when engaged.

I watched a good video where a competent person was showing the chain bouncing in a bumpy terrain, a traditional drivetrain then advanced chainrings then the same with the derailleur clutch. The clutch had certainly helped but the conclusion was it was the chainring that played the major role to keep the chain engaged.

@mfgrep and I use Garbaruk chainrings. These have hysterically high teeth to minimize any chance of the chain drop.

 

[Stefan Mikes]

Guys,
Taking the opportunity of a chainring replacement with a new 38T, 104 BCD Garbaruk one, I paid a close attention to how this specific chainring line was designed and manufactured.

The chainring is 5 mm thick. The teeth are designed and machined the way it is impossible to place the chain in a wrong pattern. A wrong tooth wouldn't simply pass through the inner chain link.
Having said the above, I can only state the chain holds onto the chainring. I cannot see any possibility to drop a chain with a Garbaruk unless the derailleur is totally out of adjustment!

To compare, Praxis chainrings are only 3.5 mm thick. Therefore, the chain has to be placed onto the chainring according to the diagram, and it looks a Praxis won't hold the chain as perfectly as a Garbaruk. I have never used a Wolf Tooth chainring so cannot say anything about it. Could anybody measure the overall thickness of a Wolf Tooth chainring?

 

[Chazmo]

During a recent ride, I had something lodge between the guard and the chainring on my bike, and it ended up bending the chainring out of shape and derailing the chain off the outside of the chainring (against the guard). I didn’t notice that the chainring had bent out of its normal planar shape. It took quite a few miles to manifest itself as a problem again, as the bike rode normally for a while. Anyway, bending back the chainring was all it took to solve the problem permanently.

I’m not sure I understand what the comments earlier are about chain bounce… All chains are going to bounce against the derailleur’s springs (unless, of course, you have a bike without a derailleur).

 

[mfgrep]

During a recent ride, I had something lodge between the guard and the chainring on my bike, and it ended up bending the chainring out of shape and derailing the chain off the outside of the chainring (against the guard). I didn’t notice that the chainring had bent out of its normal planar shape. It took quite a few miles to manifest itself as a problem again, as the bike rode normally for a while. Anyway, bending back the chainring was all it took to solve the problem permanently.

I’m not sure I understand what the comments earlier are about chain bounce… All chains are going to bounce against the derailleur’s springs (unless, of course, you have a bike without a derailleur).

I can only speak for myself. My chain drop problems with the Praxis ring had nothing to do with bounce. 100% of my chain drops occurred on relatively smooth asphalt. A high percentage of those drops occurred under motor power at low speed and on incline. As best I could tell, it seemed the problem had more to do with the chainring continuing its rotation slightly after I stopped pedaling in combination with the motor engaging or disengaging at the same time.

The bounce issue experience by others I would think might have more to do with faulty rear derailleur clutch, spring, or tension.

I had my SL in for service the other week. When I picked the bike up, the mechanic pointed to my Garbaruk ring and said "man those are some teeth!!".