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  1. #1

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    98 GP1200 Engine rebuild questions

    A friend and i picked up a 98 GP1200 with 238hrs on the gauge. The engine was out and the front piston blown. We ripped the rest of the engine apart and found no other damages besides the (1) piston, the head, and cylinder walls. The other two pistons look new and dont look like they have 238hrs on them and the crank looks good as well (everything spins smoothly and no side play in any of the rods). The cylinder that had the bad piston looks like a good hone may be all it needs (more melted metal then anything else on the walls). I have looked at the SBT engines for $1000 but dont want to throw the cash out if i dont have too. The inside of the engine cases even looks excellent. I guess my question is should i spend a couple hundred dollars on a piston, rings, hone, and resurface of the head and take the chance that the crank is good or save the couple hundred and put towards a SBT engine?? here are some pics


  2. #2

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    couple pics of the cylinder

  3. #3
    jdog800's Avatar
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    Just my 2cents. I would stay away from the stb if all possible.
    Bore the cylinders 10 or 20 over with new pistons. Head can be found cheap. I think you will come out alot better this way(alot cheaper as well).

  4. #4

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    I would like to go the cheapest route but dont want to piss away a couple hundred to only have to buy a rebuilt motor. Just trying to get as many thoughts as possible

  5. #5
    Flying Scotsman's Avatar
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    Most likely was rebuilt after seizing.
    They didnt find the cause just put it back together and seized it again.
    Rebuild your carbs and check for an air leak when you rebuild the motor.
    Scott.......

  6. #6
    james gp1300's Avatar
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    sbt engines use cheap china parts . and steel sleaved cylinders = junk motorcycle mechanic and pwc mechanic for 40 yrs . I would not use unless its just to get running and sell

  7. #7
    james gp1300's Avatar
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    crank seals fail ! that lets in air they run lean and seize. u must carefully rebuild carbs as well

  8. #8

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    Piston wash on front piston please?...seals are first suspect first, followed by oil lines, and/or lean carbs. pictures please.
    Last edited by Crazypirate; 10-01-2017 at 03:36 PM.

  9. #9
    Yamaha artisan Cutlass's Avatar
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    Fellas, this is a dead 10 year old thread.

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