1. Hello Guest. You have limited privileges and you can't "SEARCH" the forums. Please "Log In" or "Sign Up" for additional functionality. Click HERE to proceed.

Engine/carb issue with xj650 maxim '82, please help

Discussion in 'XJ Technical Chat' started by Nick S, Mar 25, 2020.

  1. NikoRx

    NikoRx Member

    Messages:
    91
    Likes Received:
    4
    Trophy Points:
    8
    Location:
    Columbus, Ohio
    Feeling jealous you got yours to idle there! Hopefully I’m not too far behind you with mine!!!
     
  2. Minimutly

    Minimutly Active Member

    Messages:
    592
    Likes Received:
    137
    Trophy Points:
    43
    Location:
    West Wales, uk
    Without trying to beat you up too much, the answer above was nearly 2 months ago. I know it's hard to sort the wheat from the chaff sometimes, but I think there is a lesson here somewhere.
    Well done, now think carefully what you're trying to achieve before doing it, do the running sync and try and set the mixtures. If you get lost with the mixture settings go back to the standard settings (2 and 3/4 turns from soft bottom if I recall).
     
    Nick S likes this.
  3. Nick S

    Nick S Member

    Messages:
    40
    Likes Received:
    3
    Trophy Points:
    8
    Location:
    Washington D.C.
    Now im just worried about the electrical system. Really hope its not related and an easy fix but the coincidence is odd (broke within a half hour of getting my idle normal) and with this bike I never know. @NikoRx didnt you say you were having some electrical issues?
     
  4. NikoRx

    NikoRx Member

    Messages:
    91
    Likes Received:
    4
    Trophy Points:
    8
    Location:
    Columbus, Ohio
    Why yes I am! I have been having the bike start about half the time, tested the starter motor and that’s ok and the solenoid is only a few years old so my guess is it’s the wiring or the starter button I replaced. Going to clean the connections and test the solenoid next
     
  5. Minimutly

    Minimutly Active Member

    Messages:
    592
    Likes Received:
    137
    Trophy Points:
    43
    Location:
    West Wales, uk
    This is my last answer to your thread. Stop bloody guessing and start being methodical! Get workshop manual and a meter, and if you can't use either then do a search, kmoe did a good how to on here.
     
    Timbox likes this.
  6. Nick S

    Nick S Member

    Messages:
    40
    Likes Received:
    3
    Trophy Points:
    8
    Location:
    Washington D.C.
    I guess my post had the wrong tone, but yes that’s what I plan to do. I didn’t do the bench sync right and I certainly suffered for it. Lesson learned, I’ll post updates on the electrics
     
  7. NikoRx

    NikoRx Member

    Messages:
    91
    Likes Received:
    4
    Trophy Points:
    8
    Location:
    Columbus, Ohio
    Got my bike to idle at 3500 and did the carb sync but I can’t get my idle lower and when I pull the throttle it ends up killing the idle. How’s yours?
     
  8. Minimutly

    Minimutly Active Member

    Messages:
    592
    Likes Received:
    137
    Trophy Points:
    43
    Location:
    West Wales, uk
    Hey - that's bad news - did you check absolutely each carb closed fully, plate tight across the body? I won't ask if you bench synced them, but assuming they all close, and you can wind the idle screw all the way out, they will close on the bike. That means your engine will idle to a stop. No air = no idle. Remind me do you have yics? Is the yics tool out? If not take it out and make sure to replace the bungs.
     
  9. NikoRx

    NikoRx Member

    Messages:
    91
    Likes Received:
    4
    Trophy Points:
    8
    Location:
    Columbus, Ohio
    Yep looks like the plates closed tightly only allowed the smallest sliver of light through when held up to a light source in a few spots, they slapped shut and look pretty tight. Bench synced yes. Yics tool yes but I wasn’t using it. Mixture screws at 3.5 and not sure how far in the idle screw is but I kept messing around with it and it just dropped. I was at least able to sync the carbs further with the enrichment off using a homemade device. Not quite sure how to approach this problem and searching the forum for answers, tried removing the air filter and it made no change.
     
  10. Minimutly

    Minimutly Active Member

    Messages:
    592
    Likes Received:
    137
    Trophy Points:
    43
    Location:
    West Wales, uk
    You "messed around with it" and it "just dropped"... let me think about this now - what does messed around with it mean? You should be closing it - actually closing the throttles, backing out the idle screw, a little bit at a time. If the rpms drop, good, up to a point. Ultimately if you back off the idle screw slowly, the rpms should drop slowly. If it gets to somewhere near 1500 rpm you should try mixture screws in a quarter each. Actually if you're weakening it too much you will hear it on the 1st or at least the 2nd.
    The last thing - if the engine just stopped you checked you weren't out of fuel right?
     
  11. NikoRx

    NikoRx Member

    Messages:
    91
    Likes Received:
    4
    Trophy Points:
    8
    Location:
    Columbus, Ohio

    Running out of fuel did happen once :(. But by messing around I mean that while the enricher was on I would turn the idle screw and slowly switch the enricher off until I got to a point the enricher was fully off and the bike would start with out the enricher if it was hot enough. I also turned the mixture screws to try and help and it appeared to work. So once it was idling without the enricher I started turning the idle screw counter clockwise to reduce the amount of airflow and there was one spot where the idle just crashes.
    I’m going to reset it all tomorrow, 3 turns for the mixture screws and 1.5 turns of the idle mixture and go from there. Logically I felt like it should have crept down to 1200 but I will figure this out yet, going to grab my manual for some bed time reading
     
  12. Minimutly

    Minimutly Active Member

    Messages:
    592
    Likes Received:
    137
    Trophy Points:
    43
    Location:
    West Wales, uk
    Hmm, Without reading back I'm guessing you only have one gauge? You really need 2. That way you can leave the "master" on no3, otherwise every time you adjust for vacuum the rpm drops and the vac on the master changes without you knowing it.
     
  13. NikoRx

    NikoRx Member

    Messages:
    91
    Likes Received:
    4
    Trophy Points:
    8
    Location:
    Columbus, Ohio

    It’s the two bottles with tubings, I did 3+4 then 1+2 then 2+3. Got the levels in each bottle as close as I could
     

Share This Page