Or is it totally automatic?
Mountain bike shifting
In the way-back days, gear shifting was an art... and unless you had a lot
of patience and a very good touch, not many of us qualified as artists. There was
much grinding and gnashing of teeth and if you were really lucky, you'd eventually get the
bike to shift from one gear to the next without discovering a non-gear in between.
Things are much better now!
But actually, shifting is so much better now that we sometimes overlook
the fact that shifting is still not totally automatic and does require a minor amount of
technique to perform as we'd like.
First, we'll look to STI road
shifting. STI is the most popular shifting mechanism found on road
bikes and stands for Shimano Total Integration. STI shifting is done on the brake
lever, with the left lever controlling the front derailleur and the right lever handling
The rear derailleur requires very little technique in order
to shift properly. Just ease up on the pedals a bit, and if you push
the outside part of the lever in (towards the center of the bike) you'll
shift to a larger rear cog, and pushing the smaller, inside part of the
lever in moves you to a smaller cog. The modern 10-speed drivetrains
do require a small amount of finesse when shifting up into larger cogs on
the rear though; it's not always enough just to click the lever, especially
as your drivetrain wears in. Sometimes you'll find you need to push the
lever just a bit past the click for it to settle into gear. If you don't,
you'll find the chain won't have made it all the way up to the next cog, or
might have made it and then jumps back down. This is the case even on the
most-expensive bikes (my own included). But generally shifting the rear
derailleur is a pretty brain-dead activity.
The front derailleur is another matter entirely. It is
Here's the technique. When you want to shift from a smaller front chainring to a larger one,
besides easing off a bit on the pedals, you push the outside part of the lever all the way in and hold
it there for a split second. It is not enough to simply flick the lever inwards!!!
For some reason, this is never mentioned in owner's manuals, and I don't think
salespeople go over it either, probably because it's become second-nature to them over
time and they just don't think about it. But if you don't hold the lever all the way
in for a brief period of time, what happens is that the front derailleur moves to where
it's supposed to, but the chain will remain on the lower chainring, scraping noisily
against the larger chainring that you want it to go to.
||This is a road bike shifter, known as Shimano STI. Just
like the mountain bike shifters, you actually have two different
levers to move, with the inside lever moving the chain to a
smaller sprocket, and the larger (outside) one shifting up to a
larger sprocket. It's shifting to the larger sprocket that
requires that you move it all the way in until it stops, hold for
a second and release.
The reason this happens is because the shifters are deliberately designed
to over-shift slightly on the way up to larger chainrings, pushing the chain just a bit
further than where it will eventually settle in order to facilitate the shifting process.
When you let go of the lever, the derailleur will come back to where it needs to be
in order to center itself over the chain while riding. If you don't hold the lever
all the way in for a brief period, it won't push the chain far enough to easily shift onto
Special note to those with small hands- this is not necessarily easy!
You may have problems moving the lever inward far enough to engage the next
chainring. And, if you have trouble holding it there as well, the the chain is just
not going to cooperate with you at all! We can make adjustments to the brake levers
to shorten the forward reach so smaller hands can more easily operate the brakes, but we
have yet to find any remedy that will allow a very small hand to have an easier time
moving the shifting levers. In an extreme case, it may be necessary to use the older
bar-end type shift levers, where you have a separate shift lever that comes out from the
end of the handlebar. Not as convenient as STI, but you gotta do what you gotta do!
For mountain bikes with
RapidFire+ shifting (where you have two shifting levers on each brake lever, one above and
one below the handlebar), the same type of situation occurs on the front derailleur.
For the front derailleur, shifting to a larger cog requires that you push the lower
lever (on the left-hand side of the handlebar) all the way in and hold it for a brief
period before letting go. Just like on the road bikes, this moves the chain far
enough onto (and slightly past) the next larger chainring so it quickly settles onto it
instead of just scraping along. And, just like on the road bikes, virtually no
technique is required to shift the rear derailleur, other than to ease off on the pedals
|Here's a front mountain bike shifter, commonly referred to as
Shimano Rapidfire. There are actually two shift levers, a
front and back one, of which the front lever is responsible for
shifting up to a larger chainring. This is the one that you
must push, and hold for a second before letting go, in order to
have a clean upshift.