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Jackie Chan Stunt Double
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21 Posts
Discussion Starter #1
I need some help from the gurus, because I am just lost with this. I decided to paint the tins (fenders, side covers, tank). I took all the tins off, painted, re-attached, and started it to go for a ride. It ran a bit rough for about 10 seconds, like when the battery is not giving out enough voltage, but then smoothed out. (New battery BTW, so knew that was not an issue). It was getting dark, so I could not see very well, but as I started to walk away to get my gear, I noticed slight clouds of smoke appearing the the beam of the headlight. The bike was running ok, and the clouds dissipated, so I thought no more about it. Ever since then, it seems to be down on power a little, but most perceptible is the fuel economy is way down.

I ride the interstates a fair amount commuting to work, and I generally was getting 200-210 miles on a tank, not using reserve. I am now lucky to get 125. I have made sure it is not gauge error as it still takes the same amount of fuel to fill it. The carbs have been cleaned and synched, and plugs are 3 months old and gapped correctly. (Roughly 1000 miles on them).
When I painted the tins, specifically the tank, I only disconnected the front and rear fuel lines and front carb vent line from the petcock valve. I did take all the hardware off the tank (filler cover and petcock) and drained all the gas. The filler neck was stuffed tightly with newspaper so no debris or residue would get into the tank, and it was off the bike and drained for 2 days, so there was little to no rust formation. Air filters are new. It is currently at the shop, where it has been for two weeks, and they have not touched it, presumably because they don't know either and are working on things they can get in and out of the shop and make some money. But I really miss my Vulcan and want to get her fixed. So please, post any ideas or things I may have missed so I can ride the open roads again.
 

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Linkmeister Supreme
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7,960 Posts
Welcome to the Vulcan madness Fiveo.

Your pre-paint fuel range of 200-210 miles per tank seems incredible to me. The tank capacity is ~3.5 US gallons. 200 miles/3.5 gal = 57+ mpg. What is your normal cruising speed? Interstate speed I would expect to be 75 mph+?? 40 mpg would seem close to normal to me.

The commonly reported fuel economy from members on this board ranges from 40-50 mpg.
50 mpg more expected when riding easy on the secondary roads.

As I recall, my bike will only go about 125 miles before I start looking for fuel.
 

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2000 VN 750 Senior Member
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2,494 Posts
If you ever figure out what changed and can return your bike to that 50+ mpg range please let all of us know what you did because it will surely be something we all would want to do. I am sure we all wish you much success in this search. 200 miles on one tank of fuel will have people and corporations knocking on your door if you can achieve it. You would be able to name your price for that information.
 

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Registered
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54 Posts
Any chance your petcock is stuck open and has leaked a bunch of fuel into your crankcase? Easy check on your sight glass to see if your level is too high. Also, I agree about 125 miles and I'm looking for fuel....
 

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Banned
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1,620 Posts
200+ miles per tank!?! don't think so on a stock tank. I'm lucky to get 110..........
 

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Jackie Chan Stunt Double
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21 Posts
Discussion Starter #6
I know it sounds incredulous. This was on a road trip to Florida, highway running, and speeds of around 60-65. I was amazed myself. I dunno. I am going to go by the shop and pick it up tomorrow, and see if I can figure it out. It is not so much the economy that I am concerned with, it is the possibility something is amiss given the smoke that appeared. I did not paint anything that would have needed to burn off, and everything was away from the motorcycle when painted.
I will go through it and double check everything, and if this is the "new normal", I am fine with it. This was the first road trip since I had bought it last August, so I was trying to pay attention to economy with nothing but highway. If everybody else is getting 125-150 between fill-ups, then I won't sweat it.
 

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47 Posts
ok i'm like everyone else the best i can get to a tank is about 125 with out useing the reserves so when you was getting 200 pluse miles to tank you was lucky and if you figure out how to get it back let us all know we would all ike that benefit
 

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Premium Member
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1,803 Posts
Welcome to the Vulcan madness Fiveo.

Your pre-paint fuel range of 200-210 miles per tank seems incredible to me. The tank capacity is ~3.5 US gallons. 200 miles/3.5 gal = 57+ mpg. What is your normal cruising speed? Interstate speed I would expect to be 75 mph+?? 40 mpg would seem close to normal to me.

The commonly reported fuel economy from members on this board ranges from 40-50 mpg.
50 mpg more expected when riding easy on the secondary roads.

As I recall, my bike will only go about 125 miles before I start looking for fuel.
X2 I average 44-48 mpg
 

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Registered
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2,687 Posts
I know what the problem is...

It's all the extra weight from the new paint. Also, it's probably not "aerodynamic paint" and it produces more air friction.


lol sorry, I have no idea what it could be... it seems to me that you shouldn't have gotten 200 miles per tank in the first place lol, maybe the error was actually there and not with the new mileage.
 

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Premium Member
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4,773 Posts
Drafting semi's at 70 mph on the Interstate I've gotten 52 mpg. Without the drafting, more like 35 mpg.
 

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458 Posts
Its got to be something else a new paint jobs not conna cause all that in my opinion. just a fluke its started after the paint job. My bike new i was getting 47-50 MPG
 

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363 Posts
could it have been that you used lead paint by mistake?????????????
the best i have gotten is about 51mpg, my average is between 40 -45
 

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Jackie Chan Stunt Double
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21 Posts
Discussion Starter #13
Well, I flushed the tank, made sure the carbs were clean, replaced the plugs with a new set of NGKs, filled the tank, and went for a ride to run out the tank. Came in at 51.68 mpg. Guess all is well.
 

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gun slinger
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1,110 Posts
i run mine like its stolen in the city , im looking for a gas station at 90 miles when i ride like that . road trips im looking at 125ish or so miles before i need fuel
 

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Git-R-Done!
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282 Posts
X 2 ↑

centurynick described my gas situation perfectly. I can't imagine getting 200 miles on a tank. So, like the others posted - if you figure out what you did, see if you can reproduce it and patent it, and you will be one popular, if not rich, guy : )

Stay cool all... Lord knows I'm tryin'!


AZ Kev
 

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Jackie Chan Stunt Double
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21 Posts
Discussion Starter #16
figured it out

Ethanol. Or more accurately, the lack of it. I have not really been checking my economy much, but last weekend a buddy and I went out riding. I filled up at a gas station I usually don't go to with super unleaded (always use super unleaded, so nothing new there.) Went on all highways and back roads with no interstates, and aside from a few spirited runs through the twisties, riding 45-65 mph. We stopped to cool off at a quick mart, and I noticed we had gone 126 miles...and I still had half a tank left on the indicator. When I got home, I parked it with 147 miles on the trip odometer and slightly less than 1/2 tank showing.
I usually keep a 5 gallon container of gas for the motorcycle and lawn equipment, and it needed filled, so as an experiment I went back to the same station and filled it up. Today we went out riding again, and before I left to meet him I filled up with the gas from the container, but do not know how much it took to fill up. I then set out to his house about 40 miles away up the interstate. Riding 75-80 mph up there. We set out, rode varying speeds on highways and secondaries between 45 and 60' then stop at a quick mart for him to get gas. The trip odo is showing 98 miles and I am at approx 3/4 tank. Since I know it was full when I left I filled up again to see what it will take and get my economy. It took 1.6 gallons, which comes out to 61.25 mpg!
I told my buddy about it and the only thing it can be is less (or no) ethanol in the fuel at this station. Nothing else has changed, from my riding to the motorcycle itself.
So, In the initial scenario where I was on a trip to the beach, filled up with a tank of ethanol-free gas, and rode 60-65mph, it is indeed probable to ride over 200 miles, just as I did, without hitting reserve. I was down to an indicated empty, but did have 200 miles on the odo from that tank.
 

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Super Moderator
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11,863 Posts
It's possible the sensor for the fuel gauge in the tank was sticking before, and got knocked back into line when you took off the tank.

I don't doubt your figures, but they are not typical. Keep in mind the fuel gauge is at best, just sort of accurate. It won't move much for the first half a tank, and the drop quickly for the other half.... And we are not talking exactly "half" either.

Since none of the figures you report mention NEEDING to switch to reserve, but seem based on gauge readings, I'd call them useless.

MPG figures should not be based on one tank of gas, but need to be averaged out over many.

If you did get 61.5 mpg.... Good for you, but you should not expect to see those numbers every time.
 

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Clint '89
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183 Posts
Fun read, they don't have it in my state yet either, there's not one single station that will sell ethanol free gasoline.
 
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