Yamaha YZF-R125 Quiz
Engine

Checking the piston pin

In this manual: Engine
General information — 15Specifications — 14Periodic checks and adjustments — 41Chassis — 67Engine — 76Cooling system — 12Fuel system — 10Electrical system — 61Troubleshooting — 13
~1min read

1. Check:

  • Piston pin Blue discoloration/grooves
    Replace the piston pin and then check the lubrication system.

2. Measure:

  • Piston pin outside diameter "a" Out of specification Replace
    the piston pin.
Checking the piston pin

3. Measure:

  • Piston pin bore diameter "b" Out of specification Replace
    the piston.
Checking the piston pin

4. Calculate:

Piston-pin-to-piston-pin-bore clearance Out of specification Replace the
piston pin and piston as a set.

  • Piston-pin-to-piston-pin-bore clearance = Piston pin bore diameter "b" - Piston pin outside diameter "a"

Test yourself

A quick Yamaha YZF-R125 quiz: every answer comes with an explanation and a link to the manual page.