Checking The Rims; Tyres And Inner Tubes; Tyres - Bosch Drive Unit Speed Manual Original

triangle backwards and forwards perpendicular to
the direction of travel.
› If you notice that there is play between the bear-
ings or if you encounter resistance when turning
the wheel, have the hub bearing adjusted by a spe-
cialist cycle shop.

16.3 Checking the rims

If you are using a rim brake, the rim is subject to a higher
degree of wear.
If a rim is worn it loses stability which makes it
more susceptible to damage. If the rim is deformed,
cracked or broken this can lead to serious accidents.
If you notice changes in a rim on your bike, do not
ride on it. Have the problem checked by a profes-
sional bike workshop.
Rims for bikes with wheel sizes greater than 24" are
supplied with a rim wear indicator. These rims have
a characteristic curve or groove that runs round the
entire circumference.
Replace the rim as soon as you notice marks (grooves,
coloured spots) in one location on the rim, if an
embossed marking has disappeared or if a coloured
marking has worn down.
If the marking consists of a groove or several points
on the rim side wall, have the rim replaced as soon as
it wears off.
22 I General User Manual

17 Tyres and inner tubes

17.1

Tyres

A large number of different tyre types exist. The bike's
offroad capability and rolling resistance depend on tread
profile.
Only inflate the tyre to the maximum permissible tyre
pressure as otherwise it may burst.
Inflate the tyre at least to the specified minimum air
pressure. If the tyre pressure is too low, the tyre may
detach from the rim.
The maximum permissible tyre pressure, and normally
also the minimum permissible pressure, can be found
on the tyre sidewall.
Always replace the tyre with a tyre of the same type,
dimension and profile as otherwise the ride charac-
teristics may be adversely affected. This can lead to
accidents.
Tyres are wear parts. Check the tread depth, tyre pres-
sure and condition of the tyre sidewalls regularly.
Replace worn tyres before using the bike.
Note the dimension of the fitted tyre. Standard desig-
nations are used when stating the tyre dimension.
• Example 1: "46-622" means the tyre is 46 mm
wide and the rim diameter is 622 mm.
• Example 2: "28 × 1.60 inches" means that the tyre
diameter is 28 inches and the tyre width is 1.60
inches.