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  1. #1

    GP1200R engine assembly questions

    Hello all. I just finished building the engine for an 02 gp1200r due to a bad cylinder and piston (and whatever else I found). I was turning the engine over by hand without the plugs in to see if the rings were holding. I found that #2 and #3 have compression with my thumb over the spark plug hole, #1 does not. I used new rings in all three cylinders, but the pistons are used. When putting the rings on the first piston, the rings stayed shut after being compressed by hand. Do you guys think they will released once fired? Or will it even fire at all?

    Second, I jumped the starter just to make sure it still works before I drop the engine in. The gear that engages the flywheel did not retract after engaging. Will this release once the engine is under its own power? Thanks, guys.

  2. #2
    TX21's Avatar
    Join Date
    May 2007
    North Texas
    My question is for the #1 piston. Did you put the rings on the piston and they stuck in the ring groves? They should not stick in there, you should be able to move them around with one finger. If it did stick on the piston thats your problem for sure. They are stuck in the ring groves not expanding enough to hold pressure on the cylinder wall. I bet the motor will run but you will know its not right, it will be vibrating crazy.

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