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Discussion Starter #1
I have a 2000 VN800A Classic, I have to run my choke for about 5 minutes in order to be able to ride away and not have the bike pop and sputter - is this normal? Sometimes I ride away with the choke on for a mile or two until the bike is ready.
 

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2001 Vulcan 800 \m/
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I have an 800A also. I do the exact same thing. I usually pull the choke out all the way, let her warm up for about five minutes; then push the choke in half way and ride about three or four miles. She still backfires a bit when I push the choke in.

I think the 800s are just notoriously cold natured. I've heard that rejetting & changing the exhaust helps, but I'm not sure.

Oh, and if it's 40 degrees out...yeah, she's cold as hell.
 

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I have a 1500 Classic, It did that wehen I got it, rejetted it and it all went away.
 

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Discussion Starter #5
Good to know that this is a normal occurance. I just read somewhere that I can richen up the fuel mix by taking apart the carb and turning the mixture knob a 1/2 turn - I 'll ask a mechanic about that one. Thanks.
 

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this is how i do it, what do you think?

My 800A backfires when it is cold. When it is below like 45F, it needs some warm up before moving.

Start the engine with the choke pulled. Open the throttle little bit to bring the rpm around 1500 - 2000. While keeping the throttle in the same position, push the choke in little bit till the rpm goes down, and pull again so that the rpm comes up to 1500 - 2000 again, and repeat this a few times. Pull the choke in, and race the engine little bit to see if it backfires. If not, my 800A is good to go. The whole process takes about 2 minutes when it is around 20-30F.

Somewhere I read that keeping little high rpm damages less the valves during cold start, and the engine oil will be pumped faster to the top part of the engine.
The very rich a/f will keep the engine running during cold start, but the engine will not warm up fast due to the excess of fuel. When the choke is pushed in and rpm goes down, I am burning up the excess fuel. The plugs will love this, I think, and the engine will warm up fast. Oh, the too-rich a/f can wash down the oil on the cylinder surface, too. I do not like to run it too long with the choke out.

Do you guys agree?
 

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Good to know that this is a normal occurance. I just read somewhere that I can richen up the fuel mix by taking apart the carb and turning the mixture knob a 1/2 turn - I 'll ask a mechanic about that one. Thanks.
You want the proper mixture for normal riding conditions. This means that you may have to use the choke when it's cold. In warm weather, you may or may not need the choke (with a proper mixture). Once the engine is warm, you should not need the choke.

Same for twisting the throttle before startup... once the engine is warm, you should not have to do it at all.

Supposedly, carbs and EFI units are set up "too lean" from the factory, which would be supported by the need for excessive choking, but one member put a stock 900 on a dyno and the fuel:air mixture was just a smidge rich on the bottom end, and above idle, was nearly perfect across the band.

The only way to know for sure is a dyno run. You could PROBABLY stand to fatten up the mixture a bit, but if you go too rich, you will waste fuel and risk fouling plugs and diluting the oil.
 

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Good to know that this is a normal occurance. I just read somewhere that I can richen up the fuel mix by taking apart the carb and turning the mixture knob a 1/2 turn - I 'll ask a mechanic about that one. Thanks.
You do not need to "take the carb apart" to adjust the mixture! You can do it in 5 secs with a carb adjusting tool or a tiny flat blade screw driver even when the engine is running (after removing the plug).
 

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I have a 2000 VN800A Classic, I have to run my choke for about 5 minutes in order to be able to ride away and not have the bike pop and sputter - is this normal? Sometimes I ride away with the choke on for a mile or two until the bike is ready.
Yes the carbed 800 is cold blooded. I suggest opening the mixture screw 1/2 turn, and then follow this start up procedure.

1. full choke - start the bike, let run for 30 secs.
2. turn choke off fully and hold throttle open manually to keep bike from stalling for 1 - 2 minutes (no longer)
3. ride off and keep revs up enough to stop bike stalling.
4. after a good few miles the bike will be warm.
 

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My '02 1500 Mean Streak was a beautiful example.
Your '02 1500 Meanie had a cat.
That's what's in the Goat's Belly (18004-1101 "Chamber-Premuffler")
The Vulcan 750 had them for a very long time. I'm not sure when they started putting them on the big Vulcans, but it was before 2000.
The 900 and 1600 don't have the Goat's Belly, but the cats are in the front end of the mufflers.
 

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800 Classic
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v800c -

I've found that my bike is cold blooded too. I live in Jax Florida. Even when it is 65F outside, the bike will need choke to start.

Example: Let's say I ride 5 miles to gas station. Fill the tank, go in for some smokes and a drink. When I get back to the bike, I will need to choke it still to get her started. The only time I don't need a bit of choke to get her to "fire" is when I've put 15+ miles on her, stop for a few minutes, then fire her right back up.

I've ridden her in 45F a couple of times, and she will move with little delay. I've not seen any trouble getting power to the back wheel at cold temps. Granted, I'm running full choke when it is that cold. Couple miles into the ride, I back the choke off, and she runs fine.

She has : Jet Kit & 2" Cobras. No other intake/exhaust mods.

-JG
 

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when the carb and the intake is cold, more fuel gets on the intake surface, instead of being mixed with air. This effectively makes the a/f very lean near the spark plug, while leaving the fuel on the intake and cylinder wall.
Choking too long unnecessarily is a bad idea. I would check often if the choke is needed or not during warm up, rather than waiting for minutes with choke on. The extra fuel on the walls will prolong the warm up.
 

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The 800B I had and the 1500 I have were/are both coldblooded beasts. What I did/do:

Start the bike with the choke. After a minute or so tap the choke knob in while adjusting the idle adjustment screw clockwise. This keeps the idle rate up. Do this until the choke is off completely. Now you are running with a normal mixture but with a little more applied throttle. Ride. As the engine warms you can readjust the idle screw back to normal, although when it runs via idle screw it's usually ready to run except on the coldest of days. Also- elevated idle takes away engine braking, so don't freak out. You'll see what I mean.

IMHO, running with the choke on is, tho not harmful, undesirable. The mixture is too rich. You'll foul your plugs prematurely, the exhaust smoke is unsightly, the popping and backfiring is embarrassing, and the smell sux. Just my .02.
 

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Rebel Rider
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You need to open the air/mixture screw about a quarter to half turn. If it's never been done you will need to drill the cap out. It can be done with the carb on the bike. Better yet is to add exhaust and scooterize the intake. Forget any jet kits, and install a 165 main, 50 pilot, and an aftermarket adjustable needle. After these mods, hold on tight because it will run like a raped ape. And it will also get better gas mileage.

For instructions go here, and look in the bike section.

The Wolf's Den; Abandon Hope All Ye Who Enter Here!
 

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Deeppurple52
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Samie-same with our 800. It is cold blooded beast when it gets down below 40. It was 30 when my wife pulled out this AM and it took 3-4 min of warm up and sputtered a little when she started out. This isn't a rejet issue with the 800, just its nature. I usually let it run for a couple of minutes, turn of choke and then shut it off for a couple of minutes while she puts on her helmet and gloves. That seems to give the best results for us. Results may vary but the important issue is that you are riding!
 

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Rebel Rider
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Samie-same with our 800. It is cold blooded beast when it gets down below 40. It was 30 when my wife pulled out this AM and it took 3-4 min of warm up and sputtered a little when she started out. This isn't a rejet issue with the 800, just its nature. I usually let it run for a couple of minutes, turn of choke and then shut it off for a couple of minutes while she puts on her helmet and gloves. That seems to give the best results for us. Results may vary but the important issue is that you are riding!

Yes, the 800 is cold natured, but just opening the air/mixture a quarter turn will help a lot. Opening the intake and re-jetting with the proper jets and needle will cure it.
 
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