MY "TEN SPEEDS"

 

 

MY "TEN SPEEDS"

 

 

 

 

SITE INDEX   FINDING   BICYCLES   WORK SHOP   TRADING   WHAT'S NEW?

MY "TEN SPEEDS"

 

 

DAMAGE - INTRO

DAMAGE - DERAILLEURS

DAMAGE - CRANK & RINGS

DAMAGE - SPOKES

DAMAGE - PEDALS

DAMAGE - SIDE STANDS

DAMAGE - BRAKE LEVERS

BRAKE CALLIPERS

DAMAGE - POST & STEM

DAMAGE - WHAT ELSE???

 

 

COMPONENT DAMAGE - DERAILLEURS

The Busted category hardly needs to be explained.  If itís broken, you either have to replace or repair it.  However, it might be a good idea to understand what different Busted Situations look like, and how the effort (cost) to repair can escalate.  As often as not, a nasty scratch that appears to be more than skin deep, is in reality, much worse than skin deep.

Consider the rear derailleur which, it should be noted, always sits in a very vulnerable position.  Because it sits so "out in the open", the rear derailleur is subject to getting bumped, banged and busted!  Whatís the repair for busted!?  Replace itÖ

But the new rear derailleur, once installed, doesnít work right.  It just wonít shift correctly, no matter how much effort and time is invested adjusting those two little screws.  It is even possible that the derailleur, no matter what you do, will not shift onto the smallest cog.  Why?

If a derailleur gets hit so hard that it breaks or gets badly banged up as is the case with the pictured, then there is a good chance that the derailleur hanger experienced impact damage also.  This is not necessarily a huge problem but it does indicate frame damage, and that in itself is a red flag.  The derailleur hanger is probably bent in, towards the center line of the bicycle and this is easy to check.

With the bicycle standing vertically, look at the rear derailleur from the back of the bicycle or from above.  The derailleur pulleys should be hanging straight down, one underneath the other, parallel to the center line of the bicycle, and in line with the cog teeth.  If these two little pulleys look like they are not parallel, there is likely a problem with the frame drops or derailleur hanger.

This is not a discussion on how to repair a bent derailleur hanger.  Rather, it is a story told to make a point.  Rough handling or crash damage, that often produces broken components, can be clues as to what condition a frame set itself might be in.  Take the time to think about what else could have absorbed the impact that caused the component damage to begin with.

I rarely run across front derailleurs that are busted.  A vintage road bicycle's front derailleur is tucked out of harm's way and rarely experiences any kind of impact damage.  However, front derailleur damage is not all that uncommon.  If the derailleur remains positioned improperly when the bicycle is being ridden, the chain will rub on the derailleur cage.  This rubbing action will cause the cage to wear rapidly.  The Huret front derailleur pictured must have run for a short while with the chain rubbing, as is evidenced by the oxidized areas where the chrome has been worn off.  I run across a great many derailleur cages, be they front or rear, that have worn so badly that they cannot be used.  This to me falls directly into the busted category, even though the part in question is not actually busted.  Just completely worn out as a result of abuse.

However, there is one front derailleur which that arrives at the Old Shed busted, as often as not.  I speak of the French made Simplex front offering to the world of bicycle transmissions.  The Simplex front chain jumper was made, in part, of plastic.  A product called Delrin, I believe.  As often as not these old units failed utterly, breaking in half and rendering a bicycle unrideable.

The Simplex front derailleur OFTEN enters the busted category because of poor design, based on selection of material used to make the derailleur.  The Delrin plastic body will frequently be cracked or busted because of this poor design, and does not necessarily reflect how the bicycle was used.

Other things to watch for when derailleurs are the issue are weak springs and sloppy feel.  Weak springs are difficult to diagnose without considerable practice.  Sloppy feel can be checked by opening up the cage and trying to wiggle it.  If it feels loose or sloppy, it is quite likely worn considerably.  The unit might still work just fine but replacement need is just around the corner.

NEXT- COMPONENT DAMAGE - CRANKS

 

 

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