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Any tips for straightening a rear hanger on a 456 summer season I think one one have made it out of the worlds strongest steel. Ive tried hitting it with a hammer bending it with mole grips its still quite warped and twisted i cant seem to get it straight, has any got any handy tips.
Cheers
Warm it up
what would be best a heat gun or blow torch
Proper hanger alignment tool is usually the best bet, might be worth a quick trip to the lbs.
A hanger bolt is the same as a chainring bolt. Bolt an old drive crank by the spider to the hanger and use it as a lever to bend the hanger straight.
Bonkers but it might work
Bike shop. Or Park [url= http://www.parktool.com/blog/repair-help/rear-derailleur-hanger-alignment ]DAG-2[/url].
A bolt with the same pitch as a hanger bolt, put through a 'long' bar and use leverage.
But to be honest, you'll be lucky to get it good enough to ensure good gear change again.
Bending it is the easy bit. Bending it to the correct place is hard.
Blow torch
Shaggy is right. Trip to the lbs. they'll have the tool and the knack. I tried to straighten mine and messed it up. They fixed it.
cheers that's the problem its in a lovely "s" shape and i know for a fact in its current shape my gears ain't working.
Trying to straighten it hardly ever works, at least not for long. Get a new one (and a toolkit spare); did you try BETD?
I don't think he's talking about a removable hanger
Peterpoddy required on this thread...he diy fixed a bent mech hanger on his Inbred 853
yep its a steel frame so it cant be swapped for a shinny new one. will call my LBS in the morning but would have liked to have fixed it my self so I can ride this weekend. Would also like to know if i can fix it in case it has an accident in the alps next year
I couldn't even get the rear mech to screw back in when I'd finished messing it up. I'd also bent the parallelogram of the rear mech - dear do overall. That'll teach me not to ride into a trench, if my bashed up face didn't!
A big (12-15 inch) Crescent wrench is good for the bending. Alignment is the issue as said above. If it were my bike, I'd let the LBS handle it. They should have the proper tools and experience doing it.
Cheers everyone, stratman yeh my rear mech has died (thanks sram for making a rear mech you cant take the whole cage off)
Did the same thing on my ss and mangled the mech, bent it back into place to get me home, local lbs properly straightened for pennies 🙂
adjustable spanner and a good eye, simples.
Cynic -al +1
Straightened the hanger on an original inbred that a mate gave me after it fell off the back of his car at 80mph and bounced across 2 lanes of the A46
Been fine since, gets 8 of 9 gears perfectly, top one is a bit hit and miss but if I could be arsed to take it I'm sure a workshop would sort that easy enough
Took 20 minutes to get it good
Blowtorch to heat up a bit, it was compressed so wheel wouldnt fit in, bent it out so I could get a 10mm threaded bar in (happened to have one in shed and easier than using a wheel)then just used combination of a big metal tube and an adustablespanner to bend it back as straight as I could by eye
It's still a bit twisted but bike serves as a run around now and has been off road a few times since (strong frames them on ones!)
8 of 9 gears perfectly,
Or take it to a bike shop, especially if you don't have the proper tools. Blow torches are not required. It will work 100% with a bit of bending.
Having seen the Proper tools in action that is best. That and someone who knows what they are doing.
Either that or look at the On One Sales page for a replacement frame 🙂 Cheaper than some hangers/drop outs out there
Useful bodge-it tool for the straightening is an old cup-and-cone axle- the thread is the same as the mech bolt, so you screw it in and 1) you've got a nice lever and 2) you can easily tell when it's straight. (if you want perfection, get a bit of threaded rod or similiar and stick it in the dropouts to give you a comparative straight line.
Now... Not sure about this but gut feeling is that heating it up isn't required but should reduce the strain on the dropout? Obviously steel's pretty bendable and durable but it'll weaken eventually... Anyone confirm or deny?
Bike upside down and adjustable spanner worked for me. You can get most of the hanger in the jaws to control the bend better. No need to heat it. Trick is getting it straight. Lbs if you are not sure. Would not be much.
What Northwind said, except I've used a complete wheel rather than just the spindle for an in-the-field repair.
The wheel gives you leverage and something to sight the alignment with.
As long as it ends up "square" - it wouldn't matter if it was 1mm further in or out as you can adjust the mech to take this into account.
Its an On-One ffs, cheap as chips, bin it and buy a new frame!
<joke!>
or maybe not?
Shaggy, I agree bike shop would be best but bike was donated to me, with the challenge of getting it back on road at zero cost using only spare partsI had lying round
I achieved that, if I was actually likely to use it I would take it to my mate who has the tool to have it sorted properly
me and my adjustable spanner will have another crack tonight otherwise pray the bike shop can fix it on sat want to ride this weekend while the ground is nice an hard. One thing though seen how touch the hanger is ive no worries about the rest of the frame.