# Bent derailleur hanger



## Janzep (Dec 30, 2019)

This hanger is bent slightly inward. Is it a result of being bent via wear and tear or could there be a mechanical advantage to aligning the cage that way? On a Canadian Raleigh with Suntour Honor RDR. The hanger is stamped 4532. Should I replace? Bend straight? Or just mount the Suntour.


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## GTs58 (Dec 30, 2019)

Those and or the Derailleur gets bent when the bike is laid down hard on that side. I've just bent them back on my Schwinns. Then make sure the cage or jockey wheel cage is not bent.


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## Andrew Gorman (Dec 30, 2019)

Are the same parts going back on the bike?  If so, do you know how well it worked before?  My first thought would be to straighten it out, just on general principles.  And while you have the bike stripped down, take a few minutes to check and adjust the frame alignment-scroll down to the picture with the string:





						Bicycle Frame/Hub Spacing
					

A bicycle frame and fork should match the wheels that are to be used in it. Older bicycles used narrower spacing, but older frames can often be spread out to match more modern wheels.



					sheldonbrown.com
				



It can make a huge difference.


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## Cranky Chain Cycles (Dec 30, 2019)

You need one of these. 



			https://www.parktool.com/assets/img/product/_productDetail/DAG-2.2_001.jpg
		



Sent from my iPhone using Tapatalk


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## bulldog1935 (Dec 31, 2019)

(probably belongs on the Lightweights page)
The correct part is easy- and cheap-enough to find on ebay, I'd probably replace it.
The RD will probably function with the bent hanger, but you might end up with shorter pulley life and possibly reduced chain clearance. 
Oops is the highest probability why it's bent, but trying to increase derailleur travel in one direction for gearing change is a possibility. 

The Suntour slant parallelogram derailleur body design patented in 1964 became the norm for everyone after the patent expired -  Shimano in 1983, and even Campy bit the bullet and copied Suntour by 1988.


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## rustjunkie (Dec 31, 2019)

this:









						FFG-2 Frame and Fork Dropout Alignment Gauge Set
					

Measure and correct the alignment of frame and fork dropouts.




					www.parktool.com
				








before this:









						DAG-2.2 Derailleur Hanger Alignment Gauge
					

Diagnose and correct a variety of shifting issues by measuring the alignment of the derailleur hanger compared to the rear wheel.




					www.parktool.com


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## bulldog1935 (Dec 31, 2019)

No offense meant, but bike shops have better tools for this task.
My Moser frame was received with dropout misaligned from shipping and poor packing - also had my International frame spread and properly aligned to 126mm OLD - quick and inexpensive work for bike shops.
I was really impressed with the tool they used to remove the fixed BB cup on my Lenton - and curb service.


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## bikewhorder (Dec 31, 2019)

Maybe I'm a hack mechanic but on an old steel bike like that I just grab the derailleur and bend it back till it looks right.  If you want to "Do it right" remove the derailleur and put a big adjustable wrench on the hanger and bend it back. Make sure the rear wheel is on and clamped down tight before trying to bend anything obviously.


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## AndyA (Dec 31, 2019)

I'm in the Hack Mechanic Club with Bikewhorder. So is Al Carell, author of "The Super Handyman's Big Bike Book." Carell says this about adjusting derailleurs: "Turn the pedals and look to be sure the jockey wheel is tracking in the center of the chain. If not, this could be caused by either the mounting bracket or the derailleur cage being bent. Either one can be bent back in place, but be gentle. The best method is to use a pair of pliers and slowly straighten the guilty party. Usually, a slight twist is all you need."

Nothing against more advanced methods and tools, but we Hack Mechanics have a proud history to defend.


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## Janzep (Dec 31, 2019)

Andrew Gorman said:


> Are the same parts going back on the bike?  If so, do you know how well it worked before?  My first thought would be to straighten it out, just on general principles.  And while you have the bike stripped down, take a few minutes to check and adjust the frame alignment-scroll down to the picture with the string:
> 
> 
> 
> ...



Yes I intend to put the SunTour RD back on. I was able to shift through all cogs before dismantling the bike. That’s why I’m wondering if the hanger was sold in that bent position. Intuitively I feel it should be flat.


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## vincev (Dec 31, 2019)

as I always say,"once you had a slant parallelogram derailleur you never go back !"


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## SKPC (Jan 1, 2020)

I also agree with Bikewhorder here although precision has it's place as well.   The human eye is capable of seeing slight bends or non-square hangers when you stand in back of a perfectly vertical frame and eyeball it.   And as he says, just carefully use a large Crescent Wrench clamped tight and go a bit at a time...good luck!


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## bulldog1935 (Jan 1, 2020)

There are some things you can do with a bigger hammer, aligning frames and removing fixed BB cups may be two, but results vary.
Somebody's bigger hammer may also be how our OP got here.
His frame may not need aligning as much as simply checking.
The part he needs to replace is out there in mass quantity and low cost.

Because they have the superior tools we can't afford, having a rapport with a smart LBS mechanic is generally a good idea.
When I spread my Grand Prix from 120mm to 126mm OLD, with its crimped TI 20-30 tubing chainstays and plate dropouts, I had no problem using all-thread, big washers and nuts.
When I bought my International frame, with its beautiful oval and not-crimped 531 chainstays and forged dropouts, the previous owner had already spread it, and it was misaligned.
Was very happy with the alignment result from my LBS.


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## Janzep (Jan 4, 2020)

bulldog1935 said:


> There are some things you can do with a bigger hammer, aligning frames and removing fixed BB cups may be two, but results vary.
> Somebody's bigger hammer may also be how our OP got here.
> His frame may not need aligning as much as simply checking.
> The part he needs to replace is out there in mass quantity and low cost.
> ...



Thanks. I do have that kind of relationship with my lbs and in that regard I had them remove the freewheel not having the proper tool. The rear wheel spun true enough for the girls I go out with before dismantling so I’m hesitant to take it back in to check the frame alignment let alone acquiring the Park tools because of $. Trying to keep the costs down so I can hopefully get $150 for it in the spring and turn my attention to the next Raleigh project.


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