Metal Machinist

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weekender

Full Member
Feb 26, 2006
1,815
19
55
Cambridge
Hi I have a request, on my bicycle I've managed to break the durailier hanger a couple of times in fact 3 times in 4 months I'm wondering if there is a metal guru who could perhaps make another one out of something better then the alloy Swiss cheese it's currently made of...??
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ta2aqe2u.jpg

You will hopefully see that these two have snapped in the same place.


Sent from somewhere?
 
Replacement derailleur hangers can be got from bike shops, steel or aluminium.

I'd err away from anything strong, a beefy hanger can weaken the dropouts. It should be the weakest part as it's the cheapest and lightest to carry as a spare. A weak derailleur hanger also baby's the rear derailleur which is also more pricey than a replacement hanger. It's a real weak point on bikes, the rear mech sticks out low and snags.
 
That's pretty much what I thought but it does seem to happen frequently, as for being cheap at £30 something quid it's getting expensive...


Sent from somewhere?
 
Ok may have exaggerated sorry 😊 but nearer £20 plus hassle of going to get one or order it. Love to know where you get them for 7 quid....!?. Just a pain in the rear that they keep braking. Also never been offered a steel alternative???


Sent from somewhere?
 
Ok may have exaggerated sorry  but nearer £20 plus hassle of going to get one or order it. Love to know where you get them for 7 quid....!?. Just a pain in the rear that they keep braking. Also never been offered a steel alternative???


Sent from somewhere?

A bike repair shop should have some. It was a way of saving a frame after the integral hanger had bent too many times and snapped off. They often used to come on cheaper bikes, just a pressed steel plate. They may/may not fit.
 
how did you do it ? As has been said a failsafe should protect the weak parts, but failsafe bits shouldnt be 30 quid a pop, not even 5 really, fuses for plugs are pennies ! How about a gear protector ?
 
First time a plastic carrier bag got blown into the chain second time I was changing gear going uphill


Sent from somewhere?
 
Um - something is wrong if you broke it when changing gear.

I strongly suspect it was bent or otherwise damaged previously. If you bend one - it will break. Aluminium doens't like being bent.

There isn't much loading on a hanger.
 
......If you bend one - it will break. Aluminium doens't like being bent......

Depends on the specific alloy and temper. Pure aluminum is extremely malleable. Even the tempered aircraft alloys are more than malleable enough to bend very complex shapes.
 
Setting a milling machine up and programming it and cutting a billet will set you back more than a replacement unfortunately. I seriously considered making some bmx parts some time ago but unless you have an entirely new improved product there's no competing with the places that churn these out round the clock. Sounds like you're having bad luck,I haven't managed to break mine yet!
 
Something I'm going to have to live with I suppose Sasquatch, incidentally what we be looking price wise if able to?


Sent from somewhere?
 
Seriously, you should not break one when changing gear. For starters, there should not be any force going through the drivechain during a gear change.
 
I was going uphill and it sort of snatched then broke
But as others have said the damage could of already been done

Sent from somewhere?
 
I'm with mrcharly on this one! Unless you take a bit hit (mountain biking sort of accident hit) you shouldn't be braking them! You shouldn't be changing up a crank rink on a hill, and it seems odd that changing up a ring on the cassette would have that much force. Might be worth pausing pedalling when changing up next time? In the meantime, you should be able to get a replacement in the £10-15 range not £30! Best of luck sorting it, and happy cycling.
 

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