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Hi everyone. I have a 99 Vulcan 750 and I have been having a problem with it. When the Engine is cold the bike starts up just fine. After I go for a ride and shut off the engine the engine wont start until it is cold. Does anyone know how I can fix this. The weather is getting real nice and I am with out my bike :(

Thanks
 

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More than likely, you have a weak battery causing the problem. Everyone suggests to swap out your wet cell battery for a maintenance free, sealed battery. Higher cranking amps and the fact that you don't need to pull your seat to check the liquid levels, make this a win/win. The starter on our bikes takes a massive amount of the amps to turn the engine and not enough is left to give good spark when the engine is warm. In my case, I already had an MF battery in mine, but still had the hot start problem. Not knowing how old my battery was, I chose to move my regulator/rectifier to a cooler location, on the left side of the bike, next to the passenger foot peg. I also did a coil wire/relay mod at the same time, firing the coils directly from the battery with higher gauge wire. This solved my hot starting problem, period. I still have the same battery a year later and my charging system still performs excellent. You need the MF battery if you don't already have one, so I'd start there.

Remember, no throttle when you first touch the starter when hot, just blip it after it starts turning and it should start. If you give it too much throttle, you'll probably get a massive backfire, when unburnt gas hits the exhaust and some fresh air!
 

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I got mine at Sears, and I think it was about $90. Just make sure you get the specs from here (nmber and stuff), and you should be able to walk in and walk out in a matter of minutes. Good luck!
 

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You can also try batteriesplus.com on line, and see if they have a local store. Got mine from them locally for $ 50 and change.

Jon
 

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I bought mine from Advanced Auto Parts. It already had the acid installed and was fully charged. The posts are backwards from most batterys though, so some creative wiring is necessary.

One positive about that battery is that the posts can be side mount and top mount. I have my leads attached to the side posts and the battery tender to the top. It works fine for me.
 

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I bought mine from Advanced Auto Parts. It already had the acid installed and was fully charged. The posts are backwards from most batterys though, so some creative wiring is necessary.

One positive about that battery is that the posts can be side mount and top mount. I have my leads attached to the side posts and the battery tender to the top. It works fine for me.
That sounds a lot like a wet acid type, you sure it's a MF AGM type? Makes a HUGE difference. Never seen them at Advanced.

Jon
 

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and the Adventure Cycle
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You can also try batteriesplus.com on line, and see if they have a local store.
I just checked their store locator out, and it turns out there's a store less than 15 miles from me.
I know where I'm going this weekend. Thanks Jon. :beerchug:
 

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HAWK
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Stinky what part of Wisconsin are you from?
I live in Illinois by the border and Lake Michigan.
 

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I found MF batteries at the local Wal Mart here. Yes, they are AGM. The only disadvantage is that you have to put the elecrolyte in and charge it. However, the cost is $68 dollars plus tax and you have it today rather than waiting for mail order.
 

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That sounds a lot like a wet acid type, you sure it's a MF AGM type? Makes a HUGE difference. Never seen them at Advanced.

Jon
It's definitely AGM. I tried to get one from motorhelmets.com but they sent me a wet acid type. Their web page was advertising the AGM and even had a chart with the benefits of AGM over wet acid, but they still sent the wet acid. I sent it back and didn't want to wait, so I found one locally. Wal-mart had them, but not for our bikes. I lucked out and found it in stock at Advanced for ~$65.

After reading some of the posts here and having the problems that I was having I would not settle for anything less than AGM.
 

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Search Goddess
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It probably won't help the hot start problem but it will help your wallet. Our bikes run fine on regular and are designed to do so.
 

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Search Goddess
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You have a maintenance free battery now? That would be the first step with our bikes and the best all around for general running and maintenance free. No acid spills, better cranking etc..
As far as checking the coils for the hot start problem, there is no "checking" that I know of. We aren't talking the coils attached to the sparkplug wires, we are talking about the pick-up coils located behind the round stator cover on the left of the bike.
Pick-up coil adjustment is this.. (from the yahoo vn750 group)

Possible solution to hard starting your VN7XX when hot.

Problem: Once my bike was good and hot, I would pretty regularly have problems restarting it after shutting it off for refueling, etc.... Once the starter was engaged, the bike would continuously turn over but never fire. After some e-mail discussion with Gary Versteegh from the main VROC board, I adjusted my pick up coils as described below. This seems to have eliminated my hard starting problems. This procedure may or may not solve your hard starting problems. Also, please note that the pick up coils are not designed from factory to be adjustable. This procedure requires modification to the stock components.

If you have any question, feel free to send me an e-mail to [email protected]. I will be happy to answer any questions.

Adjustment of pick up coils.
Remove the 3 phillips head screws on the left side. This will allow you to remove the pick up coil cover. You will need to place something under the bike to catch the oil although oil loss will be minimal. A rag was enough for me. Once the screws are removed, the cover should either come right off or you may need to pull on it. Mine was on pretty good and I had to physically pull on it to get it loose. The three screws and the cover all have separate o-rings. Once the cover is off, you will see the two pick up coils mounted to the stator cover inside two holes. They are mounted at roughly the 9:00 and 11:00 o'clock positions. Behind the stator cover, there is a rotor. You may need to rotate the rotor using a socket wrench on the shaft bolt in the center to align the small "plate" on the rotor with one of the pick up coils so that you can measure the clearance. Once you have measured one, rotate the rotor again so that you can measure the other. Gary recommends .020 clearance. Mine were about .030 or more. To adjust the clearance, remove the two screws which secure the pick up coils to the stator cover. You will most likely need to slightly elongate or slot the holes in the "ears" of the pick up coil mounting brackets. Gary indicates that a chain saw file works well for this but I used a rotary tool with a small grinding wheel on it. You will also see that there are 3 small protrusions coming out of the stator cover that each of the mounting
"ears" of the pick up coils fit into for proper placement from the factory. You will most likely have to knock the one closest to the center off to be able to make the necessary adjustment. A sharp chisel works well for this although you may want to cover the holes in the stator cover with something to prevent the little piece from falling inside the engine. Once the protrusions are knocked off and the holes are elongated, it is time to put the pick up coils back on. Set them back in their holes and start the screws. Place your .020" feeler gauge between the coil and the rotor "plate" and tighten the screws. Once you are satisfied with the clearance, tighten down the screws and do the same with the other coil. Gary recommends that you use both an impact screw driver and lock tite on the screws. I don't have an impact driver but I did use lock tite. Once both are set, put everything back together and test it out. I don't have a digital camera or I would have taken and posted some pics but you can look through the pictures in the Clymer's manual to get an idea of what I am talking about. In my manual (I assume they are all pretty much the same) the pictures on pages 296 to 302 should give you an idea of what I am talking about.

Note: This adjustment DOES NOT require removal or tilting of the engine. Just removal of the side cover held on by the three phillips head screws on the left side.
 

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Not to make this harder to understand, but on bikes, even 99's, that have been stored outdoors most of their lives, corroded wiring to the ignition coils can also have this effect, especially when the engine is hot.

A quick check with a voltmeter will tell you a lot about the wiring. Check your voltage across the battery with the key turned on, engine not running. Should be around 12.5 volts. Now check the red wire voltage on each coil, key on, engine not running. It should be very close to the same voltage as your battery. If it is down more than .5 volt, your main coil power wiring is suspect. A leaky wet cell battery causes corrosion in places that are hard to find and figure out and this test is painless and can tell you a lot. And you can do it with any motorcycle battery on the bike.

No matter what, ditch the wet cell battery. They cause more problems than they are worth!

EDIT: By the way, I'm not disagreeing with you Dianna! Just adding another possible area to look at. My first bike, 1980 KZ550, had spent so much of it's life in the weather it looked like it was covered in pig snot. All the wiring connectors on it eventually got replaced as they were all corroded. I went out one day to head home for lunch and ignition had nothing, no lights nothing. Started checking voltage, battery was fine. Went up to headlight and found the main power wire that was always live and it had 6.something volts. I didn't know it was possible. Traced it back toward the battery and on the other side of a connector it had 12 volts. Pulled the connector apart and bluish white powder fell out of it. Used a drywall screw that time to clean it out and replaced that connector that night. Once it started getting harder to start when it was hot, I did the coil wiring check on it. They had right around 10 volts! Did the coil relay mod and fixed that. I do pity the future owners of that bike though, as all my new wiring was either red or black. I never followed any of the color codes, as it never really occured to me! Oh well, if it's still running, that's probably a miracle.
 

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San Diego Vulcan Rider
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You have a maintenance free battery now? That would be the first step with our bikes and the best all around for general running and maintenance free. No acid spills, better cranking etc..
As far as checking the coils for the hot start problem, there is no "checking" that I know of. We aren't talking the coils attached to the sparkplug wires, we are talking about the pick-up coils located behind the round stator cover on the left of the bike.
Pick-up coil adjustment is this.. (from the yahoo vn750 group)

Possible solution to hard starting your VN7XX when hot.

Problem: Once my bike was good and hot, I would pretty regularly have problems restarting it after shutting it off for refueling, etc.... Once the starter was engaged, the bike would continuously turn over but never fire. After some e-mail discussion with Gary Versteegh from the main VROC board, I adjusted my pick up coils as described below. This seems to have eliminated my hard starting problems. This procedure may or may not solve your hard starting problems. Also, please note that the pick up coils are not designed from factory to be adjustable. This procedure requires modification to the stock components.

If you have any question, feel free to send me an e-mail to [email protected]. I will be happy to answer any questions.

Adjustment of pick up coils.
Remove the 3 phillips head screws on the left side. This will allow you to remove the pick up coil cover. You will need to place something under the bike to catch the oil although oil loss will be minimal. A rag was enough for me. Once the screws are removed, the cover should either come right off or you may need to pull on it. Mine was on pretty good and I had to physically pull on it to get it loose. The three screws and the cover all have separate o-rings. Once the cover is off, you will see the two pick up coils mounted to the stator cover inside two holes. They are mounted at roughly the 9:00 and 11:00 o'clock positions. Behind the stator cover, there is a rotor. You may need to rotate the rotor using a socket wrench on the shaft bolt in the center to align the small "plate" on the rotor with one of the pick up coils so that you can measure the clearance. Once you have measured one, rotate the rotor again so that you can measure the other. Gary recommends .020 clearance. Mine were about .030 or more. To adjust the clearance, remove the two screws which secure the pick up coils to the stator cover. You will most likely need to slightly elongate or slot the holes in the "ears" of the pick up coil mounting brackets. Gary indicates that a chain saw file works well for this but I used a rotary tool with a small grinding wheel on it. You will also see that there are 3 small protrusions coming out of the stator cover that each of the mounting
"ears" of the pick up coils fit into for proper placement from the factory. You will most likely have to knock the one closest to the center off to be able to make the necessary adjustment. A sharp chisel works well for this although you may want to cover the holes in the stator cover with something to prevent the little piece from falling inside the engine. Once the protrusions are knocked off and the holes are elongated, it is time to put the pick up coils back on. Set them back in their holes and start the screws. Place your .020" feeler gauge between the coil and the rotor "plate" and tighten the screws. Once you are satisfied with the clearance, tighten down the screws and do the same with the other coil. Gary recommends that you use both an impact screw driver and lock tite on the screws. I don't have an impact driver but I did use lock tite. Once both are set, put everything back together and test it out. I don't have a digital camera or I would have taken and posted some pics but you can look through the pictures in the Clymer's manual to get an idea of what I am talking about. In my manual (I assume they are all pretty much the same) the pictures on pages 296 to 302 should give you an idea of what I am talking about.

Note: This adjustment DOES NOT require removal or tilting of the engine. Just removal of the side cover held on by the three phillips head screws on the left side.
I apologize for this being off topic but you mention the pick-up coils. I have a jumping tach problem and learned it gets it's signal from the "coil". Could you clarify which coil it is and where I would look for it in order to check the connection? Thanks.
 

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Antoher Question. Could there be anything wrong with the petcock???
Not really associated with the hot starting problem. Sure it could be bad, but your symptoms would be different. Hot starting is usually caused by weak electrical, somewhere.

Have you installed an MF battery?
 
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