Motorcycle Glossary of Terms
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Tachometer - See rev counter.
Tank slapper - A motorcycle's
handlebars slap back and forth at high speed,
can be caused at high or low speed.
Tappet - A cylindrical component
which transmits motion from the cam to the
valve stem, either directly or via a pushrod
and rocket arm. Also called a cam follower.
T-bone - A type of accident
where the rider hits another vehicle in the
side, usually caused when onother vehicle
pulls out of a junction without seeing the
TCS - Traction Control System.
An electronically controlled system which
senses wheel spin and reduces engine speed
TDC - Top Dead Centre denotes
that the piston is at its highest point in
Thread locking compund -
Solution applied to fastener threads to prevent
slackening. Select type to suit application.
Thumper - A single-cylinder,
four-stroke motorcycle engine.
Timing chain - see cam chain.
Timing light - Stroboscopic
lamp for carrying out ignition timing checks
with the engine running.
Ton-up - Refers to a motorcycle
being ridden at 100 mph or over.
Top-end - A description
of an engine's cylinder block, head and valve
Torque - Twisting rotational
force in a shaft, can be measured to show
at what point an engine develops most torque.
Torque setting - A prescribed
tightness specified by the motorcycle manufacturer
to ensure that the bolt or nut is secured
correctly. Undertightening can result in the
bolt ot not coming loose or a surface not
being sealed. Overtightening can result in
stripped threads, distortion or damage to
the component being retained.
Torx key - A six-point wrench.
Trackday - Organised event
where joe public can ride around a race circuit,
subject to certain conditions.
Trumpy - Common term used
for a Triumph motorcycle.
Turbocharger - A centrifugal
device, driven by exhaust gases, that pressurises
the intake air. Normally used to increase
the power output.
TWI - Abbreviation for Tyre
Wear Indicator. Indicates the location of
the tread depth indicator bars on tyres.