Smooth Shifting With Rear Derailleur Adjustments

That whole mess on your rear wheel can look pretty intimidating.  You know…ten sprockets bunched together in a cassette, spokes pointing out like rays from the sun, and then that mysterious rascal, the rear derailleur.

Don’t worry too much about the sprockets, although I have had times when I’ve broken a tooth or two off.  I sure felt like a fool after trying to eliminate all sorts of things like the rear derailleur adjustment (over and over again), only to find that the problem of missing teeth could have been easily detected by your everyday Obsessive/Compulsive.

You know, someone who’s really good at counting things like teeth on sprockets.

Looks Complicated…And I Suppose It Is!

Other than being a genuine distraction, the spokes aren’t much of a concern in the rear hub department either, as it relates to less-than-stellar shifting.

So we’re left with the rear derailleur.

Symptoms Of Rear Derailleur Dysfunction

1).  You might notice an abundance of noise when trying to shift.  Mucho noise, not much in the way of gear shifting satisfaction.  A dead giveaway!

2).  Not being able to get into all of the gears you need for cycling fulfillment.

3).  An ‘automatic transmission’ shifting pattern. This is when your gears seem to have a mind of their own.  They won’t stay put, and switch in the worst of situations without your input.

4).  Less than ‘snappy’ gear changing.  Sluggish gear shifting may be be OK for type B personalities, but revved up lads won’t put up with a slow gear change.

Starting Away From The Rear Derailleur

What if the problem’s remote from the derailleur itself?  Like in the cable going from the shifter to the rear derailleur, or in the housing around the cable?

Well my friend, check it out.

Run your fingers over the cable to make sure there aren’t any kinks in the cable, any fraying of the cable, or any other irregularities along the course of the cable.  Sounds pretty elementary, my dear Watson.

But then again sometimes the simplest of details can derail the most brilliant of minds…which I doubt you possess.  😯

Look To The Limit Screws

Much like in the front derailleur, there are limiting screws to keep the rear derailleur from launching your chain into the spokes, or off of the smallest sprocket.  It’s not too difficult to check out your limit screw adjustment.

Just shift through the gears, and if you’re having a hard time getting the chain onto either the largest or smallest sprocket…look to the screws.

These side-by-side screws should be marked ‘H’ and ‘L’.  But of course that’s only half the story; which one controls which gear?

Does ‘H’ stand for ‘high’, as in the gear highest away from the ground, and ‘L’ for ‘low’, as in lowest from the ground?  No my friend, no.

‘H’ stands for ‘high’ as in High Gear.  So that’s the one that controls what the chain does when the bike’s in high gear.  That is the smallest sprocket.  So if you tighten this screw you will be limiting how far the chain can drop down the cassette.

Too much tightness on the ‘H’ screw means you won’t be able to shift into high gear.  Too little tightness means you’ll dump your chain off into no man’s land between the smallest sprocket and the frame.

I’m sure you have the idea now.  The ‘L’ screw limits how far the chain will go toward the largest sprocket (low gear).  If the ‘L’ screw is too tight, you won’t be able to get into low gear, and if it’s too loose, you’ll shift the chain up and over into your spokes.

If you’ve removed your plastic spoke protector (plastic spoke detectors are to a bike what a plastic pocket detector is to an engineer) in order to not look like too much like an amateur, this can be most grievous.

But then again, walking around with a pocket protector or riding around with a plastic spoke detector has it’s downside too.

Think solitary dining in the company lunchroom.

Think solo rides on country roads…never benefiting from the group pace-line.

So work on those ‘limiting screws’ and achieve cycling social satisfaction.

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