This was interesting. I went for a ride the other day after work all of maybe 7-10 miles MAYBE and I lost 1/2 a tank of gas?!?!?! What the crap would that be about? It's a 93 with vance and hines and K&N filters. Any ideas?

Well if there were no obvious signs such as the smell of gas, and leaking from a bad or loose hose, then my guess would be the float was stuck and became.. unstuck
A half of tank of gas within 7-10 miles would have flooded your carbs if it was getting there.

Was it actual loss or just gauge movement?

I've got to the point where I ignore the gauge as it doesn't seem to drop off much until the last 15 or 20 miles of the tank. It's nice to have on a bike, but it can give a false sense of security and leave you in a bind if you rely on it.

It was definitely loss. Diana...Everything checked out...I wasn't sure what could be causing that and my LAST guess what have been from the floats....I think that may be causing the problem when highway cruising and stalling out too...I had suspicions but was never sure...

Ooooops! Let me clarify.. I wasn't talking about carb float.. I was talking about fuel gauge float, or probably better known as the float connected to the fuel gauge
seen here in the bottom right hand corner
http://www.ronayers.com/fiche/400_0438/fuel_tank_vn750-a19/fuel_tank_vn750-a19.cfm?man=ka&groupid=10770&parent=10700

Our fiel gauges are also slow to start moving and seems like you go through the first half of the tank and think.. "Dang I'm getting good mileage!" then it reaches that point and seems to drop like a rock. Then mine seems to run in the red zone almost as long as it did over on the full mark.

Our fiel gauges are also slow to start moving and seems like you go through the first half of the tank and think.. "Dang I'm getting good mileage!" then it reaches that point and seems to drop like a rock. Then mine seems to run in the red zone almost as long as it did over on the full mark.

I only pay attention to my fuel gauge for a general idea of what I've got left in the tank. For a more accurate idea of how much I have, I go by mileage.
My truck fuel gauge is the same way. I can easily get to 200mi on 1/2 tank (gauge reading) but the gauge is showing nearly empty at 270mi, when you'd think I could get to 400.

But, only 7-10 miles on what the gauge shows as 1/2 tank does seem kinda odd.
Mike, was it the last 1/2 tank that seemed to go so quickly? Also, did you fill up afterwards to figure out what your mileage was?

No. I didn't fill up again...but it actually seems like the tank gauge is accurate...there's almost no gas in the tank...I threw two gallons in it after I cleaned the tank and there is less than a 1/4....:-(

I'd pull the tank and see if you've got a crack or leak someplace. That's really, really weird, but, hey, it's a machine so anything can happen. :confused:

WAIT - Whereabouts do you work?The last time gas jumped this high, folks were having their tanks siphoned all over the DC area, even out here in the country. I know we have locks on the gas caps, but they've gotta be easy to pick. I wouldn't rule that out at all.

I put it down to the people who installed the fuel guage, who assumed the tank had straight sides and is the same volume all the way down. In fact the tank is taperered and has a chunk out it at the bottom where it straddles the frame. So the first half lasts for ages but as you get through the second you can almost see the needle moving. Someone wasn't paying attention there.
Simon

Simon, that's about as good an explanation as I've ever heard. Now that you mention it, that sounds totally logical. I think you nailed it.

But guys I've ran it with against the mileage several times. This isn't the first time this has happened...just this badly...I'm seriously only averaging like 4-7 miles per gallon...it's not the gauge. Guaranteed. I just don't know what could be causing it. :BLAM:

4-7 mpg?
So with a full tankl you get.. 12-25 miles and you are out?
You have to be dumping gas somewhere, to the point that you should be able to smell it.
Either that or you have a neighbor/co-worker that is playing a joke on you. And at almost $4 a gallon.. it's not funny.
Run the bike in your drive and do a walk, look, sniff around.
If you smoke.. don't do it while you are checking

I agree with Dianna, if you are losing that much fuel, even through the carbs, you would smell it big time!!!!!!! The exhaust should almost be pouring raw fuel out the ends and what does burn would be black smoke because it would be sooo rich. How do your plugs look? If you have a carb problem of this magnatude, they should be very black.
Do you notice the fuel guage drop after the bike has been parked at work or home or do you see the needle drop while riding? At 7-10 mpg, the drop would be very noticeable and the smell would go with it.
If it happens after the bike has been parked, either someone is syphoning or again, you have a pretty massive fuel leak and the smell should point you in the right direction.

My vote is still for siphoning - it's been clear from Mike's posts that the gauge isnt' the problem, but that he's really losing fuel. If there's no obvious discharge of fuel from the tank, I'd seriously suspect some foul play. I know it's not a lot of gas in our tanks, but at these prices, it looks very attractive. And if the bike gets parked where no one can really monitor it, siphoning is way too easy.

But guys I've ran it with against the mileage several times. This isn't the first time this has happened...just this badly...I'm seriously only averaging like 4-7 miles per gallon...it's not the gauge. Guaranteed. I just don't know what could be causing it. :BLAM:

When the bike is losing fuel do you notice a loss of power? Mine was doing something similar last year and I believe the cause was a stuck float. The front cylinder would flood and then the fuel would come out the exhaust. Pulling the carbs for a good cleaning seems to have helped.

At 4-7 mpg I doubt the bike would even be running. If it was, the smell would be so strong you could taste it - and performance would take a major hit (I know that mine get's pissy if I accidentally leave the choke on).

I'm definitely siding with others that siphoning is the most likely suspect. Some cretin has likely found that your bike is an easy mark and has decided it's time to F with ya.

Now if only shock em to knock em out bike alarms were legal eh?