Compression testing 09 GS

[dashfixer]

I would like to carry out a compression test of both cylinders on my 09 GS. I have made an extension
/adaptor for the primary plug opening to allow me to use my standard engine compression gauge. My question is do I disconnect all the LT connectors to the stick coils or do I just take the stick coils off the plugs while I spin the engine over?

 

[Mistacat]

If it were mine I would remove the LT connectors to all 4 coils it only takes a couple of minutes.
Be interesting to see what your compression pressures are.
what mileage has the bike done.

 

[DrFarkoff]

Hundred percent disconnect all 4 LT circuits

 

[Smiffypr]

Personally, I would want the injection disabled too. Do it with the ignition off (throttle wide open) put power direct onto the starter solenoid.

 

[Smiffypr]

PS, you need the schrader valve to be in the bottom end of the adapter to get an accurate pressure.

 

[Steptoe]

Definitely unplug the fuel injection electrical connection .. don’t worry about coil/plug connections, you’re only turning it over on the starter for a very very short period, not running the engine at high revs continuously.

 

[dashfixer]

If it were mine I would remove the LT connectors to all 4 coils it only takes a couple of minutes.
Be interesting to see what your compression pressures are.
what mileage has the bike done.

The mileage is 84k.

 

[dashfixer]

PS, you need the schrader valve to be in the bottom end of the adapter to get an accurate pressure.

What schrader valve? I'm using my old compression testing gauge which accumulates pressure over a few compression strokes. There is no schrader valve in it. The adaptor is just a hollow tube with a seal in each end to enable reaching down the long spark plug tunnel.

 

[botus]

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