Okay so I recently bought a used GS500f with 1300 miles on it and I had a question.  My manual says it has a gas tank capacity of 5.3 gallons and from reading this site these bikes get around 50mpg.  Well i was riding the other day and the bike was acting like it was running out of gas and finally shut off so I had to pull over.  However I only had about 150 miles on the trip odometer.  I switched over to the reserve tank and stopped at a gas station but it only took about 2.5 gallons of gas to fill it.  How big is the reserve tank on this thing?

I won't get into gallons as it gets confusing with UK and US being different, Your bike should have a tank capacity of about 20 litres including about 4 in reserve. I used to get to about 180 miles before it started spitting and farting about.
Keep track of your mileage for a while and see how it compares. When you fill up after using res make sure you switch back to the normal position after filling.

Before I filled up, I switched it back to the normal tank, would that make a difference?  The guy that I bought it from said he usually filled up around 200 miles on the trip odometer

If you went 150 miles on 2.5 gallons that's 60 mpg which is what I get all summer long and about 50-55 mpg in the winter on my 02 GS with 5.3 gallon tank.  I hit reserve at 230 miles give or take in the summer and around 200 miles in the winter and get about 4 gallons if I fill up around 240 miles.

There is only one tank for the 5.3 gallons and a tube inside the tank picks up the gas at a higher point with the selector valve at the on position and at the bottom of the tank with the valve at res.  Doesn't matter when you switch it when filling.  You should be going further before hitting reserve.

california bikes also have smaller tanks for some reason.

if you're in CA, that may be why.  I also fill up @ 150miles because I can't get much further than that without switching to reserve.

As far as I know it was originally purchased in IL

sounds like someone cut your tube 

My last two tanks I hit reserve at 134 and 126 miles and averaged 50-51 mpg.

On my 06 i normally switch to reserve around 220-225.  I normally get right at 58-60 mpg

Well I guess I'll just keep an eye on it once it hits 150 again and see if it does it again

Alright well right around 120 miles I got kind of nervous (didn't want to run out of gas on a busy road)  so I pulled over and filled up...

It took 1 gallon until the pump auto shutoff...BUT

I pulled the pump out and looked inside and noticed there seemed to be a lot of room left.  So I risked it and with the pump nozzle halfway out of the tank started pouring more gas.  Well it ended up taking a little more than 3 gallons until the gas was at the top of the tank.

Is this happening with you guys too?  If you put the nozzle all the way in will it stop early?  Hopefully I can hit 150+ miles w/o running out of gas this time haha.

If you look in your manual, it tells you to fill it up the bottom of the brim of that like hollow cylinderish thing inside the top of the tank.  Maybe someone can describe it better, but if you're not filling it to the same spot consistently, it's difficult to gauge your actual fuel economy.  The manual should also have the specs for your bike, if you have the manual.

Quote from: PaviSays on July 05, 2009, 06:11:43 PM
If you look in your manual, it tells you to fill it up the bottom of the brim of that like hollow cylinderish thing inside the top of the tank.  Maybe someone can describe it better, but if you're not filling it to the same spot consistently, it's difficult to gauge your actual fuel economy.  The manual should also have the specs for your bike, if you have the manual.

I've got it somewhere around here...not sure where exactly though.  I guess I didn't read the part about how to correctly fill the tank lol.  I figured it would be like a car and just stop when the pumps shut off.

Quote from: billytuffnuts on July 05, 2009, 06:18:09 PM
I've got it somewhere around here...not sure where exactly though.  I guess I didn't read the part about how to correctly fill the tank lol.  I figured it would be like a car and just stop when the pumps shut off.

Every time I fill up I:
1. Put it on the center stand
2. Fill to the lower lip of the fill-cap (it's very easy to see where the gas level is when the bike's on the center stand)
3. Take a picture of the trip odometer reading with my phone
4. Save the receipt and enter it into fuelly.com: http://www.fuelly.com/driver/discourteous/gs500f-2

Haha it's cool man, we're all here to learn.  The only reason I actually read my manual was because I had to wait two days before I could go back out to the guy's house to pick up the bike, and it was the only thing I could do other than gaze at the key, haha.  

When I fill up, I don't put the nozzle in like a car, I watch it fill up until it gets to that brim and release it manually.  My bike's a 1997 naked model though, so it could be different for the faired version; I'm not sure.  Who knows, what's everyone else do?


Oh, center stand, that's probably a good idea.  I've been using the sidestand.  A centerstand would probably be more accurate.  No phone for me though, and the receipt doesn't work at my preferred pump.   So I just have to drive home repeating the numbers in my head, haha.

I just sit on the bike, and hold the nozzle down so that the end of the nozzle is roughly at the end of the cylinder thing in the tank.  During fill-up I lean (bounce) left and right a little to let any air escape.  Once it starts to get close to the end of the cylinder I lift up the nozzle and just use less pressure on the pump lever to get gas more slowly, so it doesn't splash.  Then I close the tank, reset the odometer, switch back to On (almost always ride to reserve), start up and ride off.  Never got less than 215 to reserve doing it this way.

Edit:  Mine is also an 06.

Ever since my first bike(1983 yamaha dual sport), which had a broken trip odometer, I've been in the habit of refilling the tank every 100 miles. If you don't pass gas stations often that might be harder, but where I live I don't have any trouble passing a gas station when I need one.

The other thing to consider, which I don't understand other than companies being lazy, is that a lot of tanks have a spot that's lower than the fuel pickup(which I fought with all weekend as I was cleaning cleaner, acid, and tank sealer out of the stupid petcock hole.) Even if you dump 5 gallons into your tank, you're never going to actually ride 5 gallon worth because the petcock will stop getting gas before the tank is actually empty. The was the only time I really really missed fuel injection. The last tank I had to reseal had a giant hole in the bottom, I could just stick my hand in with a towel to dry it out. No need for me to stand there like a jackass shaking my gas tank for 20 minutes at a time.

The other benefit to refilling the tank every 100 miles, is that you know there's always atleast some gas in your tank. As I found out after I pulled Heather's GS out of her parents shed after it was parked for 4 years.... she wasn't in the same habit that I am, and running your tank almost empty and parking it in the shed means a bit of rust and an entire lost weekend for me....

I have an '04 which has the same tank and usually will just stop for gas whenever i get near 180-200 miles on the tank except when i completely forget about and wonder why my bike is sputtering and then shuts off.  I just put down the sidestand and sit on the bike and balance it to be standing upright while fueling and fill it up right to the bottom of the filler neck on the cap.  I never use the autostop thing on the pump as it won't even come close to filling the tank and actually avoid some gas stations in my town since it is a PITA to fill a motorcycle since they always stop even with the gentlest squeeze and i can see that the tank isn't close to full no matter where i hold the nozzle.