2 rear hangers in 2 days

[budegan]

I'm baffled and wondering if someone can advise me.

A couple of weeks back I snapped my rear hanger. I ordered 2 new ones (a brand called Pilo) a replacement and a spare, and this week got around to putting one on.

First ride on it yesterday and it snapped.

So in the evening I put the spare on, rode on it this afternoon (in a crit) and that one snapped!

I've had a quick look online to see whether whether it's Pilo that's the problem, but nothing is leaping out.

Worth mentioning that I think the original hanger breakage was due to the rear mech (di2) being faulty. It's now been replaced and today's breakage occurred with the new one on.

Also worth mentioning is that I've been using a hanger alignment tool when fitting.

 

[Tricycle Rider]

I'm baffled and wondering if someone can advise me.

A couple of weeks back I snapped my rear hanger. I ordered 2 new ones (a brand called Pilo) a replacement and a spare, and this week got around to putting one on.

First ride on it yesterday and it snapped.

So in the evening I put the spare on, rode on it this afternoon (in a crit) and that one snapped!

I've had a quick look online to see whether whether it's Pilo that's the problem, but nothing is leaping out.

Worth mentioning that I think the original hanger breakage was due to the rear mech (di2) being faulty. It's now been replaced and today's breakage occurred with the new one on.

Also worth mentioning is that I've been using a hanger alignment tool when fitting.

Pictures of what you speak of are always helpful. Well, to me anyway. (Pictures including your bike, and the packaging and product you had just recently purchased.)

I'm not a pro at this (I'm merely a tinkerer), but if you provide pictures I'm sure the pros amongst us will be able to provide you with some kind of answers.

 

[budegan]

Unfortunately I've broken down the relevant bits (removed the chain etc).

TBH there wasn't much to see anyway other than a snapped hanger!

 

[Tricycle Rider]

Re:

Unfortunately I've broken down the relevant bits (removed the chain etc).

TBH there wasn't much to see anyway other than a snapped hanger!

You mentioned riding in a crit - is this a road bike you're talking about? (Apologies, my knowledge of MTB-ing is severely lacking. So if you MTBers do crits, again, I apologize.)

 

[JayKosta]

When you used the alignment tool, how much 'alignment bending' was done? And after installing the new hanger, did you go thru a test of having the rear wheel off the ground and going thru all gear shifts - and visually SEE and HEAR that everything was running with good alignment.

And make sure there is enough clearance between the deraileur parts and the sprockets so there is adequate room for everything to move without mechanical interference.

Jay Kosta
Endwell NY USA

 

[Tricycle Rider]

When you used the alignment tool, how much 'alignment bending' was done? And after installing the new hanger, did you go thru a test of having the rear wheel off the ground and going thru all gear shifts - and visually SEE and HEAR that everything was running with good alignment.

And make sure there is enough clearance between the deraileur parts and the sprockets so there is adequate room for everything to move without mechanical interference.

Jay Kosta
Endwell NY USA

This is very good advice -

Do you have a bike repair stand at your disposal so you could test and run your shifting through, budegan?

 

[froze]

There are other reasons for hangers breaking to like the freehub that's not very free anymore, which could put tension on the derailleur which then pulls on the hanger. Or, a stiff chain link can put stress on the derailleur which in turn...well you get the idea. Of course then there's the bent derailleur that can do the same thing. Poor tension on the cable can do that especially if the hanger is of cheap quality metal. The B screw set to close so the upper pulley touches the sprocket through the chain could cause this. Chain too short could cause that but you said the chain is stock and no problems till lately, but a short chain is the leading cause of breaking hangers. Being that the problem is lately I would be looking at bent parts, but if you haven't ever had any crashes, then I would be looking at the freehub or stiff chain link. Of course it's also possible you're buying poor quality hangers, but hangers don't typically break, and yours have been doing that out of the blue, so if you never had a minor accident then again it echos back to the freehub or a stiff chain link.