hard to/wont start after running/riding a while - Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums
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post #1 of 33 (permalink) Old 06-07-2017, 05:41 PM Thread Starter
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hard to/wont start after running/riding a while

my 89' 750 has always been hard to get started after i ride a bit and turn it off ....if i go to the store or to get gas, it always is difficult to start,only does this when warmed up... It starts 1st time every time when cold, has a new battery and runs great when i ride otherwise.What is going on ?..i need advice please, thanks everyone...
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post #2 of 33 (permalink) Old 06-07-2017, 06:13 PM
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Is it an AGM battery or wet cell?
What exactly do you do to start the bike?
Do a search for "pickup coil mod"

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post #3 of 33 (permalink) Old 06-07-2017, 06:22 PM
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Try choking it when you restart if it has sat a few minutes, mine cools off quick.

Mine also starts best if I don't open the throttle.

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post #4 of 33 (permalink) Old 06-08-2017, 02:02 AM
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Originally Posted by clb3chey View Post
my 89' 750 has always been hard to get started after i ride a bit and turn it off ....if i go to the store or to get gas, it always is difficult to start,only does this when warmed up... It starts 1st time every time when cold, has a new battery and runs great when i ride otherwise.What is going on ?..i need advice please, thanks everyone...
I bought my '03 last summer and had the very same problem. Drive a short distance and it was very hard to start. The last time it happened I was out gassing up, and the battery ran down before every getting it to fire up again. The people on here are a godsend! After reading through the threads I found a few possible causes, but settled on the suggestion that my wet-cell battery wasn't beefy enough and that I should invest in an AGM battery. I picked up the one listed below from O'Reilly for about $85 and the hard starting problem hasn't been an issue since. If you don't get this one just be sure to get one with 200+ cold cranking amps, and make sure you get one that has an "L" at the end, otherwise the posts will be reversed and the cables won't reach. Good luck!

Super Start Extreme Power Sport AGM - Battery

Line: SSB | Part # ETX15L
1 year limited warranty
UPC: 83996010826
Cold Cranking Amps (CCA): 220 CCA
Voltage (V): 12 Volt
Cold Cranking Amps (CCA): 220 CCA
Terminal Type: Top Post
Voltage (V): 12 Volt
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post #5 of 33 (permalink) Old 06-08-2017, 02:27 AM
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mine did the same thing with a wet cell. used to strap a jump pack to the bike.rrrr rrrr rrrr rrrr BOOM!

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post #6 of 33 (permalink) Old 06-08-2017, 10:54 AM
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I had this exact same issue, I have a '06. Come to find out after cleaning the plug on my rectifier and checking into the pickup coil that solved most of it. It still does it at times but I have to really ride her far to muck up again. My last ride I did a 100 mile stretch with no problems. If your still full stock then relocating the essential electronics is a key also, keeps them from getting so hot and breaking out. These guys really have great ideas and are very knowledgeable and without them I would have been walking many times

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post #7 of 33 (permalink) Old 06-08-2017, 02:29 PM
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Hard Starting

I have had several vn750's. the AGM battery was the answer as far as hard starting was concerned. That and I found it worked better if I didn't touch the throttle until it started to fire. I only chocked it when the weather was cold.
I have to quit looking at this forum or I might buy another one.

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post #8 of 33 (permalink) Old 07-16-2017, 05:29 PM
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A strong battery covers up a weak rectifier issue...... mostly. Always upgrade the battery when you can, but fixing the hot start issue in a case like this exact one is 90% regulator plug related. It likes to brown, burn, and blacken those connectors. Monthly cleaning and inspection is a really good idea on these bikes. One of the biggest tale tell signs of the issue is a dynamite stick of backfiring while trying to start it.

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post #9 of 33 (permalink) Old 07-16-2017, 07:17 PM
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On my 91 I put in an AGM battery and Iridium plugs. Cold starts or hot,I don't hold down on the start button,instead I just touch or "bump"the start button and it fires up after a few tries. Good luck.
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post #10 of 33 (permalink) Old 08-10-2017, 09:33 PM
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Trying to understand

With respect to the new battery and R/R connector theories I fail to comprehend the mechanism here. Is the idea that the R/R causes the charge status of the battery to be weak OR does the R/R somehow short when it gets hot? As was mentioned above a great battery can mask the real problem ... which I still do not see. Comments solicited please.

Is the consensus that this is an electrical problem? Ignition maybe? Has anyone installed a voltmeter on their bike? Has anyone checked for spark when the bike is hot? Does a shaky battery weaken when hot?
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