Spotting Gear Box Problems; Checking The Wheel Bearings - MINSK Repair Manual

easier. If you are having trouble undoing a screw then hit the handle end of the
screwdriver with a hammer or rock a few times while the other end is in the head
of the stiff screw. This is usually enough to jar any rust or grime from the screw's
thread thereby allowing it to turn. Otherwise use some lubricating spray if you
have it.
Spotting Gear Box Problems
There are basically three things that can go wrong with the gears. All involve a
bit of complicated work as the gears are deep inside the engine and require more
tools than what you would normally carry. So when you begin to feel one of the
following problems, head immediately to a mechanic.
Sometimes the teeth on a gear cog can break off or wear down. When driving
using this faulty cog you will hear a nasty grinding noise and the gears might slip
suddenly into neutral. This noise will only happen when you are in that particular
gear. Get it replaced quickly as eventually you might not be able to use this gear at
all and the bits of metal floating around in the gear box might do further damage
to other parts.
Secondly, the large coiled spring which returns the gear pedal back to its
horizontal rest position after you move it up or down when changing gear can
break or stretch. If this happens then you will always have to move the gear pedal
with your foot back to its horizontal rest position before you can change into
another gear.
Thirdly, you might have a problem with two things called pawls which make
the clicking sound when you change gear. Essentially their job is to lock in the
change of gear by acting in a similar manner as the deadlock on a door. If a
deadlock is loose because it has no spring then you will not be able lock the door
because the latch will not enter the hole in the door frame. If you get stuck in a
particular gear and can't change either up or down then these pawls or the springs
which keep them tight are not doing their job. A mechanic will have to clean
them, file down the pawl and replace the springs. Nasty job to do alone.
Checking the Wheel Bearings
Faulty bearings in the axle of your back wheel will allow the wheel to wobble
around and lead very quickly, if left unchecked, to strain on the chain, the drive
sprocket and the back wheel sprocket. This will stretch or wear them down and the
chain might slip off. Faulty bearings in the axle of your front wheel, on the other
hand, will render steering and braking more dangerous as the front wheel will
wobble when you turn or brake. So it is important to look out for weak bearings
and get to a mechanic should there be a problem. They are quite hard to fix
yourself as you need a special pair of pliers and a hammer.
To check the front wheel's bearings, get a friend to hold the bike upright, grab
the front wheel and shake-wobble it from side to side. If it moves around the axis
©Digby Greenhalgh 2000
Minsk Repair Manual
40