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Discussion Starter #1
After I get to my destination and try to start it up to leave it doesn't like to start. It just back fires. Even just going to the local grocery store and back. The warmer the motor is (the longer the ride) the harder it is to start. It starts great cold. Please help. Thanks:motorcycl
 

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If only it had 6th gear..
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I did the Pickup coil clearance mod in hopes of fixing this issue but it did not completely fix the issue.
First off, I would check your battery and have it load tested.
It could be that your battery is weak. The other thing I found was that by turning the bike off via the kill switch on the handlebar BEFORE turning off the ignition with the key will help since it will disable the headlight until the bike is running, therefore removing the load of the headlight while trying to start the bike.
Good luck! let us know what works for you.
 

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Old Twistie Sticks Rider
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The other thing I found was that by turning the bike off via the kill switch on the handlebar BEFORE turning off the ignition with the key will help since it will disable the headlight until the bike is running, therefore removing the load of the headlight while trying to start the bike.
Don't tell me that now... lol, I have always put a toggle switch on my head light to kill the power to it on start up... I'll try that and see if it will work on my present bike...
Have a good one...Old Dog...
 

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My '02 model already has the headlight setup like that. It doesn't come on until the engine starts. If the engine starts and dies, you need to turn the ignition off and back on again to reset it. This appears to be an afterthought solution for problem that should not have existed in the first place.

I have never messed with the pickup coils, and don't plan to. I've noticed most people get very little improvement from this. I believe the problem lies with the weak starting system rather than anything wrong with the engine or carbs, though I don't know how this causes such a difference between cold starting and hot starting.

Whether cold or hot, I feel the engine turns over too slowly, probably not fast enough to get a good spark. Part of that problem may be in the starter itself. I took mine off, took it apart, and used a whole can of contact cleaner to clean it out. It was filthy. Tons of black dust. I did not replace the brushes, though I probably should have. That made a very noticeable improvement in how fast the engine turned over. Hooking up jumper cables from a car battery also makes a noticeable difference.

So with a clean starter and a car battery, it seems to fire right up, which would seem to confirm my original feeling about the starting system. I think it needs a bigger battery and a stronger starter. New properly gapped plugs may help as well, though I got the expensive irridium plugs everyone recommends, and did not notice a difference.

One more thing I have noticed. If you use the choke (on mine anyway) even when warm, it seems to help starting. I don't know whether this indicates a carb problem or not. I have my pilot screws 3 turns out.
 

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In your original message you mentioned backfiring. I am curious if you have messed with the idle mix screws. If you did, it is possible that you have them set improperly. A lot of people talk about setting them out to enrich the fuel mix (reducing popping in deceleration). I too have tried this, but the popping stopped only when I was out about 3 1/2 turns. After the bike cools down again it would be hard to start and it seemed to backfire which indicates to me too much fuel in the system.
My personal experience is that in setting the fuel mix too rich, and using the choke tends to flood the carbs and cause a backfire once it does ignite.

I would turn the screws back to about 2 turns out from bottom and see if that helps with starting cold.....assuming you did turn them out to begin with.

Just throwing out ideas...hope you get it solved!
 

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95% of the time the cure is putting in a new AGM battery. If you have a regular wet cell that's not brand new.

Tip off is the backfires. This is fuel that was not igniting.

If after you clean off all your terminals and install a new AGM or one of the new lithium iron batteries , and still have a problem, you can try the pick up mod... But as I said 95% of the time the AGM does the trick.

I found that when hot, just giving it no choke but just a slight blip of throttle worked best as I hit the starter button.


Many vulcans are of course "old" now, so cleaning the contacts and brushes on the starter itself can help too...

Using the kill switch makes no sence as it only cuts power to the coils and let's all the lights stay on. Turning the key to off makes more sence as it resets everything. If your battery us so weak it won't start the bike with the headlight on that means you need a new battery........:doh:
 

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1986 VN750
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A new AGM battery sorted my hot-starting problem out in an instant.

She starts right-up when warm with no choke and a little flick of the throttle.
 

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Discussion Starter #10 (Edited)
Thanks everyone. I'll start with iridium plugs and an AGM battery. Is there more than one type of AGM battery? Should I be looking for a specific one? Amps/cca?
What the heck does AGM stand for? What should my spark plug gap be set at?:
Thanks again. Happy Turkey Day
 

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1986 VN750
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If you're running NGK iridiums, then I believe they're gapped (correctly) @ 44 from the factory. AGM stands for Absorbed Glass Mat - a newer type of sealed, maintenance free battery. You're looking for CCA of 200+. The model in my signature is rated @ 210CCA.

Note the model number of most VN750 batteries, as they'll have an L in it, which means the terminals are flipped from their 'normal' position. We did not have any local so I got a 'non-L' battery and seated it backwards. The leads had no problem reaching. I also had to remove the plastic stand-off on the bottom of the battery.

Be sure to follow the charging instructions that come with the battery, and get a decent 1.5A trickle charger/maintainer. They have a nice $20 one at Wal-Mart.

Best of luck!
 

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AGM = Absorbing Glass Mat.

I do think the 3 best things to cure this is the maintenance free battery, iridium spark plugs and the pickup coil mod.

I only did the AGM battery and the Iridium spark plugs and I have no trouble with hot starts at all. Cold starts also improved.
 

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iridiums cured mine, plus it will be the last set of plugs youll have to buy unless you run into some serious carb issues!
 

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I have a WestCo battery and love it. I have them in all my bikes but one, and they work great. You can get them at westcobattery.com. Be careful about getting sealed AGM batteries from Batteries Plus. I bought one from them for my XT225, (needed it right then) and it was dead. Took it back, it tested bad, they gave me another one, and said it tested ok. It does start the bike ok, But I had it a few weeks now, and cannot get a green light on the Battery Tender, which tells me something is still wrong. I'm going to call and ask them about it. It has a one year free replacement warranty, and I'm holding onto the receipt.
 
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