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Valve timeing help

Discussion in 'Great Lakes U.S.' started by Cafe Murdock, Sep 14, 2019.

  1. Couple days ago my 79 xs650 with aftermarket dual exhaust and pod filters started running a little off at highway speed everything else is ok . I thought my carbs just needed to be resynced . So i hooked up a vacume gage to my carbs and according to 2 it at lik 3 n 4 grand ish eg 70mph. cuz i got rid of my old tach and i am useing a tc bros overdrive sprocket the vacume gage reads late valve timeing . Now normally thats not a problem but my left cylinder plug when i try to remove moves about half a turn n then gets really really tight n hard to turn im afraid of stripping the plug hole n the jug .any thoughts on the plug problum aand im thinking a good re time should fix my late valve problem . I just wanted to conferm a couple things n get sum inputs from the rest of the xs comunity thanks .
     
  2. grizld1

    grizld1 Grumpy old man Top Contributor

    Try removing the plug with the engine warm; expansion difference between the aluminum head and the steel plug should help you. If it were mine I'd work the plug back and forth, extracting a bit at a time and hoping for the best. There are only three adjustments that will affect valve timing (tappet clearance, deck height, and position of sprocket on camshaft) and only one of those can be done without pulling the engine out of the frame.
     
    gggGary likes this.
  3. Ive tryed it warmed up n same result ive got spaire just n motors i jt didnt wanna have to change top end over sumthing so simple but i i w gonna try n work it till it cum out one way or another so i can reset my timeing n see wat my Gage's say then
     
  4. kevski

    kevski XS650 Addict

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    kent uk
    Has it been running fine up until now?
     
  5. gggGary

    gggGary Stop that! XS650.com Supporter Top Contributor

    add oil, rust buster to threads. Maybe run it a bit with the plug loose.
     
    grizld1 likes this.

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