Cobra CX50 2014 5R King, Руководство пользователя

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Service
Trained technicians with precision gauging and proper assembly fixtures carefully
assemble all Cobra engines to specific tolerances. If you feel you have the skills, and
the appropriate tools, to perform the following service tasks please follow the
instructions closely. The part numbers are listed throughout to help you when ordering
parts from your local Cobra dealer.
If you don’t feel comfortable with the service work, log on to
www.cobramotorcycle.com
to find a Cobra dealer or Call 517 437 9100.
Engine Service
One method for determining whether the top end of your engine needs rebuilt is to
perform a WOT (Wide Open Throttle) kicking compression test. Before performing the
procedure please read the caution notes below.
CAUTION:

There appears to be a wide range of variability in reading compression gauges
across the country.

The head volume of this Cobra Motorcycle is very small and so requires many kicks
~20 before you establish the most accurate reading possible.

Because of the geometry of the spark plug used in this Cobra Motorcycle, the
adapter used with your compression tester must have a similar volume protruding
into the combustion chamber to establish an accurate value.

Length of hose on the compression tester will affect the reading. The shorter the
hose length the more accurate your reading will be.
Because of these difficulties in measuring an
absolute compression value, a useful
relative
value can be achieved by testing your bike’s compression with your own
particular gauge after a new top end or when the bike is new so that you know what
your particular gauge reads on a ‘fresh’ engine. When it has dropped to 90% of its
original value the engine will be down on power and would benefit from a rebuild. When
it’s dropped to 80% it really needs rebuilt! Using the table below will help you determine
monitor the condition of your top end.
Engine is Fresh
Measured Value
Engine Down on Power
Measured Value * 0.9
Engine NEEDS Rebuilt
Measured Value * 0.8
Example 110 psi 110 psi * 0.9 = 99 psi 110 psi * 0.8 = 88 psi
Your Values
Procedure for Compression Testing
1. Shut off the fuel petcock.
2. Install the compression gauge into the spark plug hole.