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Servicing
CBF125 See Owners Manual or Haynes CBF125 Manual for instructions.
Someone did email me about the valve cover screw threads being weak and
he stripped them.
A Honda dealer mechanic told me he has had no problems, but when you tighten,
use very little force.
He said you only need to slightly compress the rubber, it will then shrink and
expand to maintain an air tight seal.
So be careful or ask a Honda mechanic for advice or try to remember how tight it
was when you removed the valve cover.
But if you know what your doing and just want the figures.
With a cold engine, line up the T on its side (not the F on its side).
Intake 0.08 mm, Exhaust 0.12 mm
CBR125 look in the
Haynes CBR125 manual.
But if you know what your doing and just want the figures.
The Honda CBR125 owners manual does not tell you how to adjust the valve
clearance,
but in the specifications near the end of the manual it will tell you what the
valves should be set to.
Its probably Intake 0.06 mm, Exhaust 0.27 mm with a cold engine, I know that's
correct for the Carb (has a Choke lever) model.
YBR125 look in the Haynes YBR125 manual.
But if you know what your doing and just want the figures.
With a cold engine
Intake
0.08 - 0.12 mm,
Exhaust
0.10 - 0.14 mm
If you use a torque wrench, Intake and Exhaust covers = 18Nm, Camshaft Sprocket
Cover = 10Nm.
If you do not use a torque wrench, be careful, see CBF125 section above since
YBR125 may also be susceptible.
General Advice (for CBF125. CBR125, YBR125)
If you still have excessive noise from the top of the engine after adjusting
the valves, your CAM Chain is probably in need of adjustment or repair.
Do not ignore it, the CAM Chain can easily blow up your engine if ignored (see a
mechanic if your not sure about what to do).
New valves will change their clearances more regularly until run in (bed in),
so you will have to check more often when running in.
It's not recommended to ignore checking the valve
clearance but if you do,
listen (helmet off) to the valves at the top of the engine
when its running, if they are excessively noisy (clatter, clatter) the clearance
is to big and needs adjustment.
If one of the valves goes quiet its clearance is to small
and must be adjusted immediately to prevent damage.
Performance drop, bad idling, problems starting or
compression drop could mean the valve clearance is to big or small, check
immediately to prevent damage.
Valve clearances normally increase due to mechanical wear,
but can sometimes decrease.
If the valve clearance is to big the only damage you are likely to have done is
increased the wear rate of the valve.
Valves wear out (normally takes a very long time and high
mileage) and can be replaced, when
the gap is to large they wear out far quicker