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  1. #1
    CB750 New Member enterlance's Avatar
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    Jan 2018
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    san jose
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    Unhappy Tried to fire up now the bike won't light up

    Hi DOHC guys!
    I'm new to this forum, and I'm just trying to build my first project ever!

    Here's my problem, I am not very knowledgeable and definitely need your help!:
    The bike starts / lights fine before I found it leaks fuel. I took the carb out, disassembled it, replaced the T tube O-ring, and it was OK now. Tried to installed the carb and tried to fire up the bike, all I heard after pressing start button was a little buzz sound from the central of the bike. Then this happened: I tried to turn the key to ON position, no lights on the dash. Tested the voltage of the battery: 13v. Starter relay solenoid shows 14v. The fuse box (on the handlebar) looks fine, no fuse burnt. What could be the problem? Please light my path with your wisdom!! Thank you!

  2. #2
    CB750 Addict Skelee's Avatar
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    Nov 2017
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    Hamilton, Canada
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    117
    Ground wire maybe. Ignition wires? If solenoid ok you would hear clicking.

    Sent from my SM-A520W using Tapatalk

  3. #3
    Moderator dirtdigger's Avatar
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    Feb 2012
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    Black Hawk SD
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    2,650
    I suggest getting a different meter first...no way you can get a higher voltage at the solenoid then you get at the battery. The battery is the highest voltage in the system when not running, everything else will be the same or slightly lower. You need good test equipment before you can accurately test and find your issue. But check everything you touch when doing the carbs something you moved or removed is the issue if it started after you worked on it.

  4. #4
    CB750 New Member enterlance's Avatar
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    Jan 2018
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    For some reason after a can of beer and I turned the key ON, it just cured. Yeah I thought that meter was somehow strange. Thank you guys for the advice!

  5. #5
    CB750 Addict Wez_'s Avatar
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    Apr 2017
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    Enfield, CT
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    269
    Those magnetic starter switches get sticky. Not sure if that would prevent the instrument cluster lights from illuminating, but perhaps the voltage got low and that's why no illumination, then once the charge dissipated back to the battery, the voltage and lights returned, and the magnetic starter kicked in. I had similar symptoms with my bike at first until I got a replacement magnetic starter switch.

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