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  1. #1
    johnboygtv's Avatar
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    Question stock 800 compression

    Hi guy's


    did a compression test on my gsx today and the rear pot was about 142 and the front about 152 cold, what would you guy's think i should do? full topend rebuild,just rings?? im also thinking about skimming the head aswell for abit of performance

    any help wouls be great
    regards john


  2. #2
    mibunkerking's Avatar
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    ouch. this would be a decision on your part. some people say 5% others 10%. at 10% your still okay.

    you need to find out why its droping. probably beacause of it seized at some point. you should take the head off and look for any signs of alumimium on the cylinder walls. if so you might be able to get away with a hone provided that there are no deep scars. snap a pic and post it once you get the head off. i am assuming that you have already change the fuel lines right?

  3. #3
    johnboygtv's Avatar
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    Cheers for the reply, the fuel lines dont degrade like in the US,something to do with the fuel we use,rebuilt the carbs last year,hardly any crud in there! im up for doing the topend,but in acouple of weeks i will take the head off and have look,respraying a mate superjet,so should'nt be on here really

  4. #4
    96XPSS's Avatar
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    Pull the head John and inspect the cylinder for excessive scoring and or aluminum smeared on the sides.

    Are you running a pipe? Sorry I can't remember.

  5. #5
    johnboygtv's Avatar
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    Hi chap

    no pipe just R&D f/a rejetted to your specs and R&D nozzles.if i get a chance this week i'll take the photo of the head and bore ok

    cheers john

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