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.

1981 xj650 need help ASAP! Colorado!!!!

Discussion in 'Western US and Canada' started by Chrisco19, May 16, 2021.

  1. Chrisco19

    Chrisco19 New Member

    Messages:
    4
    Likes Received:
    0
    Trophy Points:
    1
    Location:
    Colorado
    My 1981 Yamaha xj650 maxim bought for 100$ wouldn’t start said it’s was the starter, I replaced the battery starter solenoid starter motor new spark plugs new fuel lines new petcock. New fuses did an oil change and new oil filter everything I can think of, was having a high rpm problem was a throttle cable that was pinched, rode it for the first time 10 miles yesterday no leaks just fine, got home put cardboard under it to leak search incase watched for 10 minutes all good then went inside came back out fuel was coming out of the line on the underside of the air box, I need help I’m completely lost and don’t know anything about bikes it’s all been YouTube and manuals. I did have the endings turned to off but the petcock was on prime? Did it just overflow the carbs? Is something wrong? Carbs brand new and cleaned with rebuild kits so new pilot jets and everything else etc
     
  2. pauldale999

    pauldale999 Active Member

    Messages:
    311
    Likes Received:
    32
    Trophy Points:
    28
    Location:
    Nottingham, England, UK
    Could be the prime position. When you choose prime, it feeds fuel directly to the carbs, non-stop and like you suggested they might be overflowing because you had stopped operating the machine. They will overflow out of the pipe at the back of the carbs, into the airbox.
    Try turning back to the 'ON' position, (in this position the machine will only start requesting fuel with the engine running) start the machine and let it idle, whilst revving every now and then.
    Also, whilst it is running, try lightly tapping the float bowls of each carburettor with a light (rubber if poss.) hammer and race, because one of your sliders might be sticking inside one of the carbs, causing the overflow into the airbox.

    Hope this helps.
     
    StarGeneral likes this.
  3. pauldale999

    pauldale999 Active Member

    Messages:
    311
    Likes Received:
    32
    Trophy Points:
    28
    Location:
    Nottingham, England, UK
    because one of your sliders......or the floatbowl!..... might be sticking
     
  4. Toomanybikes

    Toomanybikes Well-Known Member

    Messages:
    2,740
    Likes Received:
    773
    Trophy Points:
    113
    Location:
    Tsawwassen bc
    Bad float valve or too high a float level.
     
  5. Chrisco19

    Chrisco19 New Member

    Messages:
    4
    Likes Received:
    0
    Trophy Points:
    1
    Location:
    Colorado
    Seems like the issue stopped anytime I turn the bike on I keep it on fuel instead of prime and nothings leaking yet, although this morning pretty cold I was hearing subtle low backfiring through the exhaust, was wondering if maybe I should clean the exhaust out? Or what do U think?
     
  6. Toomanybikes

    Toomanybikes Well-Known Member

    Messages:
    2,740
    Likes Received:
    773
    Trophy Points:
    113
    Location:
    Tsawwassen bc
    So if you park the bike and leave fuel tap on or res it won’t happen? The prime is for when you have no fuel in tank and you want to fill the carbs. After that “on” or “res” any other time is the norm as vacuum tap opens when bike runs.
     
    StarGeneral likes this.
  7. Chrisco19

    Chrisco19 New Member

    Messages:
    4
    Likes Received:
    0
    Trophy Points:
    1
    Location:
    Colorado
    Yep I leave it on fuel never had the problem again
     

Share This Page