1. Some members were not receiving emails sent from XJbikes.com. For example: "Forgot your password?" function to reset your password would not send email to some members. I believe this has been resolved now. Please use "Contact Us" form (see page footer link) if you still have email issues. SnoSheriff

    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.

My "new" 80' 650 has horrible top end noise

Discussion in 'XJ Technical Chat' started by nejeff, Apr 16, 2012.

  1. nejeff

    nejeff New Member

    Messages:
    15
    Likes Received:
    0
    Trophy Points:
    1
    Just bought bike and no.2 is ice cold and motor makes worst noise I ever heard! No. 4 starts working after about 2 minutes (yes, this thing actually starts and idles!). Not sure what I am going to find tomorrow. Carbs rebuild is a gimme but something must be wrong in that top end. Any thoughts?
     
    nejeff, Apr 16, 2012
    #1
  2. nejeff

    nejeff New Member

    Messages:
    15
    Likes Received:
    0
    Trophy Points:
    1
    Oh, and I can feel kind of a vibration on the no. 2 exhaust pipe I don't feel on the others.
     
    nejeff, Apr 16, 2012
    #2
  3. hogfiddles

    hogfiddles XJ-Wizard, Host-Central NY Carb Clinic Moderator Premium Member

    Messages:
    14,821
    Likes Received:
    5,151
    Trophy Points:
    113
    Location:
    near utica, new york
    could be you have a valve issue and have to do your clearance checks. You're probably going to want to pull the valve cover off and check the condition of the cams themselves, too. Make sure the guides look good, the gears look good, the chain is not slack, etc..... I did take one engine apart that was a strong running engine, and found a broken cam gear mount on an exhaust cam one time. Apparently it had happened before, and I could see where the bolts had scored the inside of the chain tunnel, but fortunately hadn't damaged anything else.

    We need more info, though...

    How many miles?
    previous shim checks?
    compression test?
    previous owner do any 'repairs'?
    previous owner actually KNOW how do the repairs?
    etc...

    If the previous owner is a member of this list, no offense intended.....:)

    Dave F
     
    hogfiddles, Apr 16, 2012
    #3
  4. nejeff

    nejeff New Member

    Messages:
    15
    Likes Received:
    0
    Trophy Points:
    1
    If it's as simple as valve adjustment that would make my day. PO bought it from another PO and both did not know a thing about motorcycles. I'm fairly sure the oil is at least 6 years old. I was actually shocked the thing started judging by the condition of everything when I went to look at it. It has about 18,000 on it and that's about all I know. The valve cover looks to have been removed and siliconed on in the past so maybe it had some attention under there? maybe? ...probably not. Valve cover is coming off tomorrow and compression will also be done. Hi haven't had a chance to get to far into this XJ thing but can I assume my motion pro valve tools for my XS will work on the XJ? Are these two motors of the same family? I will report back with my findings...Thanks!
     
    nejeff, Apr 16, 2012
    #4
  5. nejeff

    nejeff New Member

    Messages:
    15
    Likes Received:
    0
    Trophy Points:
    1
    Did compression test this morning. 1, 3, 4 are at about 120. No. 2 is at 90. Checked all clearances and they are a little tight but nothing crazy or far out of wack. Ideas guys?
     
    nejeff, Apr 17, 2012
    #5

Share This Page