Lekkie rings failing on BBSHD

[Diggs]

Any one else having trouble with 52T Lekkie rings failing on a BBSHD? I've had two of them fail now both in the same place. The first at about 2,000 miles and the second after another 4,500 miles. I even turned down the amps to 25 after the first one failed but it didn't seem to help much. I've spent a bunch of time with Search but didn't see a mention of another failure. I wouldn't be adverse to trying a Gustavo ring at this point but I can't find one with 52T (or greater). Offset on other rings is a problem.

 

[Matze_Senpai]

interesting. could the size of the chainring be the reason ? maybe they didnt use enough material to keep it strong enough. does lekkie have lifetime warranty? i would message them with this fault and maybe u get a replacement

 

[Diggs]

I'm sure the spidery nature of the 52T is a factor in its failures. I'm trying to figure out how common the failures are. Admittedly the failures were on steep hills but nothing cars wouldn't go. I never go off road.

They warranty for a year and each failure of mine has been a bit longer than that. Their web site says they want to know about failures so I'll give them a shout.

 

[amberwolf]

One reason for failures in a single specific place like that is a design or machining flaw leaving a stress riser there, but I don't see one. If it failed on a different leg of the spider it might be something more general, but if it's that specific leg every time, it probably has to do with the angle that leg joins the ring at, and or the stress riser issue.

If it's different legs each time, I would guess fatigue from flexing sideways cyclicly, from a slightly off-center chainline, such that the chain to the rear sprocket is pulling sideways enough on the chainring at the top of the cycle vs the rest of the rotation that it eventually fractures the spider.

If this is the case, then you can straighten the chainline and eliminate the problem.


(Most of the time I see problems with chainring deformation or damage when middrives (or even high-torque human pedalling) are used with the rear sprocket left shifted into the higher gears for high torque situations, instead of downshifting to the lower gears as the system is designed to be used).

 

[Diggs]

(Most of the time I see problems with chainring deformation or damage when middrives (or even high-torque human pedalling) are used with the rear sprocket left shifted into the higher gears for high torque situations, instead of downshifting to the lower gears as the system is designed to be used).

No doubt I was left-shifted into what I would call lowest gear/first gear/highest ratio (32T/52T) when it failed (I think). I spend 90+% of my time in the highest/fifth gear/lowest ratio (14T/52T) so that has a more centered chain alignment but is where I really pour on the power at times.

I've been in touch with Lekkie. They requested the specifics. I'll see what they have to say. I'm surprised they make this chain ring specifically for the BBSHD so light considering the torque involved. A couple of extra ounces of material for strength wouldn't bother the BBSHD.

 

[richj8990]

Or...most chainrings only last about 1500-2500 miles even without electric power going through them. Add additional power/torque on a chainring and the life will shorten. Many people make the generalization that a mid-drive will shorten the life of the drivetrain components about 50%. If it's a small 250W mid-drive and the drivetrain is well-maintained you could maybe get the same life/mileage out of the drivetrain parts as for a normal bike. But a 1000W BSSHD? You were probably lucky to get 2000 miles out of the ring. People snap chains, taco cheap aluminum chainrings, etc. all the time with that much power running through the drivetrain.

As a comparison, I Strava follow a pro mountain biker who climbs pretty fast, his garmin measures around 700-900W peak human power during some of the climbs. He's also complaning a lot about busting his rear derailleur, going through cassettes fast, etc. So this happens no matter what kind of power is used, (super)human or electric.

 

[prawn]

Any one else having trouble with 52T Lekkie rings failing on a BBSHD? I've had two of them fail now both in the same place. The first at about 2,000 miles and the second after another 4,500 miles. I even turned down the amps to 25 after the first one failed but it didn't seem to help much. I've spent a bunch of time with Search but didn't see a mention of another failure. I wouldn't be adverse to trying a Gustavo ring at this point but I can't find one with 52T (or greater). Offset on other rings is a problem.

View attachment 334648

I had a 36t lekie on my first build (26" giant anthem x4 )i had my chain drop after hitting a bit of a bump and when it did ,almost half of the teeth were ripped off , prior to installing the bling ring i had the same chain dropping "accident happen to me more than a few times with the stock bbshd chainring and that was tough enough to survive. Although it is my fault for not having my drive train sorted properly I was still quite a bit disappointed after spending so much $ . I thought it would have been tougher in the circumstances....I now run a 54t steel chainring i salvaged off a folding ebike ,on my new bbshd build ( intense socom fro 26") with a 10 speed sram xo free hub and shifter,lekkie buzz bars , I also use the lekkie chainring spacer I had left over from the bling ring.