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SPECIAL FEATURES OF TRIATHLON, TRACK BIKES AND TIME TRIAL MACHINES
TIME TRIAL BAR END SHIFTERS
With Shimano, SRAM and Campagnolo bar end
shifters for triathlon and time trial use the shifter is
pressed downwards to move the chain to the smaller
sprockets in the rear, i.e. to achieve a higher gear, and
to the smaller chainrings in the front, i.e. to achieve a
smaller gear. By pulling the shifter upwards the chain
can be moved to the bigger sprockets and chainrings.
The shifting of a gear lever is communicated to the
rear derailleur via bowden cable. Then the rear derail-
leur swivels, causing the chain to climb onto the next
sprocket. It is therefore important when changing
gears to continue pedalling smoothly without force
as long as the chain is moving between sprockets or
chainrings! There are, however, special guides in the
chainrings of today's bikes which allow for switching
gears under force. Changing gears under load short-
ens, however, the service life of your chain consid-
erably.
Furthermore, this may cause the chain to jam be-
tween chainstay and chainrings (also referred to as
"chain-suck"). Therefore, avoid changing gears while
pedalling with force, in particular when changing
gears with the front derailleur.
TRACK BIKES
Track bikes do not have brakes. The rear wheel hub is
without freewheel. The cranks always rotate with the
wheels. Therefore, when you start riding a track bike,
let yourself help by an experienced trainer.
Bar end shifters operate rear and front derailleur
Rear derailleur
Track bike
Note that the distance you need to stop
your bicycle increases, while riding with
your hands on aerobars. The brake levers are not
within easy reach.
Track bikes differ completely from usual
road racing bicycles. Carefully approach
riding without freewheel and without brakes.
AFTER AN ACCIDENT
1. Check whether the wheels are still firmly fixed in
the drop-outs and whether the rims are still cen-
tred with respect to the frame or fork. Spin the
wheels and watch the clearance between brake
pads and rims. If the width of the clearance chang-
es markedly and you have no way to true the rim
where you are, you will need to open the brakes a
little, if necessary, so that the rim can run between
the brake pads without touching them. In this case
remember that the brakes will not act as powerful-
ly as you are used to. For more information, read
chapters "The brake system" and "The wheels".
2. Check whether the handlebars and stem are nei-
ther bent nor ruptured and whether they are level
and upright. Check whether the stem is firmly fixed
in the fork by trying to twist the handlebars relative
to the front wheel. Also, briefly lean on the brake
levers to make sure the handlebars are firmly fixed
in the stem. For more information, see chapters
"Adjusting the Canyon road bike to the rider" and
"The headset".
3. See whether the chain still runs on the chainring
and sprockets. If your bike fell over to the chain
side, check that the gears still function properly.
Ask somebody to lift the bicycle by the saddle and
gently shift through all the gears. Pay particular
attention when switching to the small gears, mak-
ing sure the rear derailleur does not get too close
to the spokes as the chain climbs onto the larger
sprockets. If the derailleur or the drop-outs have
been bent, this can cause the rear derailleur to col-
lide with the spokes – risk of accident! This in turn
can destroy the rear derailleur, the rear wheel or
the frame. Check the front derailleur, as a damaged
front derailleur can throw off the chain, thus inter-
rupting the power train of the bicycle (see chapter
"The gears").
AFTER AN ACCIDENT
Check the reliable clamping of both wheels between the drop-outs
Try twisting the handlebars relative to the front wheel
Verify that the chain still runs on the chainring and sprockets
Please note the particulars given in chap-
i
ter "Special characteristics of carbon", as
well.
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