Difficult start after refueling - Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums
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post #1 of 15 (permalink) Old 05-04-2018, 11:23 PM Thread Starter
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Difficult start after refueling

So this issue has been going on ever since I had the bike, every time I go to fill up at a gas station, it seems to be very difficult to start the bike after. I'm trying to fill below the filler neck. It starts fine if I shut off/turn back on, just only after filling the tank it backfires and doesn't want to kick on right away. Right now I'm actually waiting for it to cool down some before trying to start it again... Any suggestions?
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post #2 of 15 (permalink) Old 05-05-2018, 04:11 AM
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There are quite a few posts about doing the pickup coil mod. Search for 'hot start' problems.

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post #3 of 15 (permalink) Old 05-05-2018, 07:35 AM Thread Starter
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Here's the thing though, it's not hot starting that's the problem, I can start & restart no problem, it's only after filling up the tank that it doesn't feel like firing up. It cranks, does one pop, then just struggles to fire up.
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post #4 of 15 (permalink) Old 05-05-2018, 09:28 AM
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Sounds just like mine if I open the throttle while cranking. I got in the habit of using the choke after fill ups, starts right up. If I don't use the choke, it just cranks and backfires.

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post #5 of 15 (permalink) Old 05-05-2018, 10:51 AM
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the hot start issue shows itself most noticeably when shut down hot, 3-10 min wait (filling up), then try to restart.

mine did the exact same thing.. let it sit 10-15 mins (sometimes less) and it will fire right up.

pickup coil mod fixed it

2005 VN750

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post #6 of 15 (permalink) Old 05-05-2018, 09:36 PM
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Yes try pickup coil mod and relay mod. Made a world of difference

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post #7 of 15 (permalink) Old 05-06-2018, 02:59 PM
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I set my pickup coils to 0.018" and just barely crack the throttle when cranking and it starts hot perfect every time.

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post #8 of 15 (permalink) Old 05-07-2018, 10:03 AM Thread Starter
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I've heard of pickup coil mod but I'm honestly not exactly understanding it. I know you're supposed to trim something & set another thing to 0.020", but what exactly does this mean? What is this the distance between?
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post #9 of 15 (permalink) Old 05-07-2018, 11:23 AM
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Also should point out a weak battery can cause starting problems too...switching from the wet cell that comes with the bike to a good AGM battery cured my starting issues...(which were only noticed after filling up or stopping a short time). I doubt your issue is related to the gas tank..

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post #10 of 15 (permalink) Old 05-07-2018, 12:21 PM
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Iridium spark plugs and/or K&N drop-in air filter replacement fixed mine. Not sure which one or both are needed since I did both upgrades at the same time. Problem went away immediately and now going on 8 years since with no problems. Added a little extra overall performance as well. Plus, easy upgrade.

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