poor compression

Discussion in 'Touring Models' started by 02EGlide, Apr 11, 2009.

  1. 02EGlide

    02EGlide Member

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    Hi all,

    New here and already have a question. I have an 02 twin cam and did a compression test today because I'm using too much oil, 2 Qts per 1800 miles. The compression test readings were Front-140 Rear-125 psi. I had the throttle wide open while cranking the engine over. I also squirted oil in each cylinder and the compression went over 150 psi on each cylinder. I am leaning toward replacing the rings....do I just replace the rings?...money is a big factor right now. Another option would be to keep riding it for awhile, at least until cooler weather at the end of the season and then do the work. Thanks
     
  2. jimharvey1

    jimharvey1 Junior Member

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    I know money's tight but if I were going to tear a stock motor down for a top end, I'd put it back together with a big-bore kit (95"). You didn't mention how many total miles were on the motor. That would determine if I were going to do a top end or a complete overhaul.

    If you are still looking at only replacing the rings, make sure you measure out the jugs and wrist pins and at least run a hone through the cylinders to break the glaze. A valve job probably wouldn't hurt either.
     
  3. 02EGlide

    02EGlide Member

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    Bike only has 24000 miles on the clock
     
  4. silentflyer

    silentflyer Active Member

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    Take a look on ebay, a bunch of jugs/pistons from guys who have done upgrades, like new parts, some deals out there.
     
  5. glider

    glider Veteran Member

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    With 24K on the bike, there's a possibility of a broken ring but if you are taking it down that far either replace the jugs, or hone them or even go big bore like posted above. Tear it down first to see where the problem is before getting the new parts.
     
  6. 02EGlide

    02EGlide Member

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    Thats what I was thinking Glider. I also was wondering if you think it can wait for another 2 or 3 thousand miles...it still runs good, just I have to keep an eye on the oil.
     
  7. glider

    glider Veteran Member

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    Something that is repairable now may not be in a few thousand more miles. If there is scoring in the cylinders from a broken ring, it will only be worse with time.
     
  8. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

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    If you are trying to save money, I would do rings, have cylinders honed, valve job. As Glider said above, don't wait since a broken ring may trash a jug and increase your costs. But if you can save everything you have now and just buy new rings (obviously new gaskets too!) you are money ahead. Doesn't make sense NOT to do the valve job, IMHO.

    TQ
     
  9. 02EGlide

    02EGlide Member

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    Thanks for everyones input. I did stop by the dealer to pick up some oil yesterday and was descibing the problem to the service manager and he asked me if the bike was at operating temperature when I did the compression test. I was testing it cold....I'm going to try it tonight at operating temp. I'll keep you posted. He also mentioned that he believes the oil consumption was probably more of a valve guide issue due to the smoking on decelleration. Anyway..the saga continues.