70 miles till empty?

[vegbiker]

I have a fuel dilemna. After 100 miles, I have to refuel or I get the ol' sputtering/running out of gas thing. I once made it to 114 miles, but to be safe, I stick to 100 (nice, even number).

This evening, I had only ridden 70 miles when it happened. I was on a long, freeway bridge (I-90 heading out of Seattle), it was dark, and obviously not a safe place to "breakdown." I pulled over, put the petcock to RES: nothing. I put it to PRI: it started up. I rode 8 miles on PRI until I found a gas station.

Is this usual? How many miles do you get before filling up? When I picked my bike up at the shop earlier this year, the mechanic mentioned something about a hose in the gas tank that when too exposed, will make the bike sputter. I guess keeping the tank full eliminates that problem, but what's with the hose? Have you heard of that before? How do I get in more miles before filling up again (I can see gas in the tank, even when it's "empty")?

[chimivee]

I went through the same thing a few months back... got some good info here.  First off, how much gas do you fill?  Do you stop when the pump shuts off?  If you're filling 2-2.5 gal, then 100-120 makes sense.  But that means you can probably get close to a gallon more in the tank - you just have to keep topping it off.  It takes forever: Fill it until the fuel starts to come up the filler neck, wait a couple seconds for it to go down, repeat, repeat, repeat, etc.  It was also suggested to me to fill the bike while sitting on it.

That said, I usually don't fill the tank to the absolute max, cause it's such a nuisance.  So I'll go about 130mi before hitting RES (this is on a CA model w/ a smaller tank).  But when I've really filled the tank to the max, I've gone 180 mi before hitting RES.

You should have quite a bit of fuel left when you hit RES... I think it's close to a gallon.  I doubt you could use that entire gallon, but it should be good for at least 25+ mi.   I've found that if I don't switch quickly enough to RES when it starts to sputter, I often have to go to prime to get fuel in back in the carbs.  Once fuel is flowing again, I can switch it to RES.

If you're still having problem getting fuel in RES, you may need to clean the in-tank filter screen (easy).   Haven't heard of the hose issue your mechanic mentioned.

[snapper]

I get two trips in and out of Boston.  40 miles each way.  So 160 miles....  If I do some riding around then on the way home of day two I have to go to reserve.  If you go to reserve when you start to feel the sputtering then no prime is needed.  Though, as Chimivee stated, if you wait too long you have to put on prime for a few minutes so the bowls can fill up again.  Then you can take it off prime and go back to reserve.

Good luck!

[BadBatzMaru]

i get about 37MPG on my '91 .... depends on driving conditions of course (me being in NY) (and I suppose it depends on what average speed since i use odometer to figure this out, and we know speedometer's inaccuracy is speed dependent, right??, well at least i think...). I usually fill'er'up round 100 miles just to be safe (there is no place around here safe to run out of gas... taxis will just make pizza out of you :x  :x )... '01+ models have slighlty bigger tanks I believe... ~5.8 gallons as opposed to ~4 but don't quote me on the exact size... you can do a search here and find it, i remember reading a thread about it a while back.

[Kerry]

chimivee is right.  If you're inserting the filler nozzle all the way into the gas tank (like the picture at the top of the Stupid Magnetic Tank Bag Tricks thread), and you stop when it shuts off automatically, you're missing out on a LOT of miles.

I hold the tip of the nozzle a little below the lip of the filler hole.  When the fuel level reaches the bottom of the "filler neck" I stop pumping and gently rock the bike back and forth.  The filler neck sticks down into the tank a bit (on purpose, I'm sure), so rocking the bike lets some of the air next to the filler neck escape, and the fuel level drops a little bit.  I give a little shot with the pump and then "rinse and repeat" until the fuel level doesn't drop anymore.  I routinely go ~180 miles (with a non-CA bike) before I have to switch to REServe.

The '89-'00 tank holds 4.0 gals in California, 4.5 elsewhere in the US.
The '01+ tank is supposed to hold 5.3 gals everywhere.

[vegbiker]

Thanks all!

I do keep the gas nozzle out of the tank and keep filling until it reaches the "neck." BUT...I've never rocked the bike or waited for the fuel level to go down more and then refill.

Also, I should try to learn how to switch to RES while riding - it would save me the hassle of coasting out of the way of cars  

[Kerry]

I do keep the gas nozzle out of the tank and keep filling until it reaches the "neck." BUT...I've never rocked the bike or waited for the fuel level to go down more and then refill.

Hmmm.  Missing out on the small amount of extra fuel (.2 to .4 gallons at most) wouldn't explain your VERY low pre-RES mileage.
The only way to know for sure what's going on (without taking things apart) is to perform some "tests".

1) I have found that sometimes, after having to switch to REServe, I can switch back to ON for many miles.  (?)  I'm not sure, but this may tend to happen during all-out, fuel-guzzling runs.

2) Perhaps your fuel system "thinks" it's a partly-ON, mostly-REServe setup.  (Don't ask me how.)  I wonder just how far you can go on REServe?  As long as you're in town, you should still be able to get a few miles in PRI when the REServe runs out, so you might consider "finding the bottom".  You could take along a (full) fuel container of some kind just in case.  I've found that a fuel bottle for a white gas camp stove will hold almost a quart, which should get you several miles.

3) If it turns out that you really are "out of fuel" at ~100 miles, there must be some sort of blockage somewhere.  I would suspect the in-tank filter.

Also, I should try to learn how to switch to RES while riding - it would save me the hassle of coasting out of the way of cars  

It just takes a little practice.  Try it first with the bike stationary, and your left foot on the peg.  The petcock should be somewhere near your upper calf muscle.  Once your hand knows where to find the switch, try switching it while "under way" in a parking lot or a deserted road.  It's pretty easy once you can eliminate the "OH NO!" stress factor.

[mjm]

Are you keeping the bike upright while filling or is it on the side stand?

Back in the early 70's I sold a friend my old X-6 Hustler and he kept complaining about how few miles it went per tank even though he was getting good milage - one day we rode together and I wached him fill it with the bike on the side stand.  After he was done, I put the bike on the center stand and put another gallon in.  That was with a 3 gallon tank - I bet its at least that big a difference with a GS.

[glenn9171]

I just put 199.3 miles on a tank of gas that included a fair amount of "brisk" country riding and lots of indicated 90MPH (8000rpm) highway miles before hitting reserve.  It took 3.8 gallons to fill up.  That's 52.4MPG.  I have never hit reserve before 180 miles on the trip odometer.  This is on an '01 model.

[vegbiker]

Another round of thanks, guys! I do fill up while sitting on the bike, so it's relatively upright. I think I'll perform Kerry's tests (with a spare bottle of fuel with me) next time I do some city driving. I'm thinkingthat maybe it's time to check the filter too.

[Diderich]

Does this always happen on the highway?  I wonder since you are saying this happened on the highway after only 70 miles, if you aren't suffering from the usual highway fuel starvation problem that a lot of GSes tend to have.   If this is happening in town too, then...

I think i remember a post about a clogged vent in the gas tank creating vacuum in the tank as it emptied, causing fuel starvation?? This could be a problem too, if it's not myth or legend..Opening the tank for a second, and putting the switch to PRI for a couple of minutes to refill the floats, and then back to ON would test that.  Should give you another 50 miles on ON.

[Remy_Marathe]

Okay, so this is an ancient thread but I experienced the exact same thing vegbiker did today.  I know it has nothing to do with my fill-up habits, as I usually fill at the exact same pump of the exact same gas station with the bike in the exact same position.  Usually I get 110-130 miles on a tank before reserve.  Today after riding the bike harder and faster than I have before (7-8k rpm's at 75-85mph) for about 15 minutes, it began bogging down on me.  This was at 70 miles on the tank.

The stuttering continued as I slowed to around 35mph (end freeway), and ceased as I switched to reserve.  So I THINK switching to RES cured it, but it might just be a time-lapse illusion, and actually recovered because I slowed down.

The problem didn't persist after I stopped, and switched to regular fuel line again.  When I fueled up at my usual spot, it only needed 1.6 more gallons and my gas mileage was standard.  So the gas was in there.

I've had the tank off, inspected all the main lines for blockage (except for the California carbon canister), verified a nice clean and functioning petcock; found no troubles in any of it.

So what the crap is going on there?  What is the "usual highway fuel starvation problem" that Diderich mentioned?  I have a Cali tank, with carbon canister and all; is that capable of causing vapor-lock?  Vegbiker (if you still check the forum), did you ever come up with anything?

If the bike stutters in the twisties I'm boned and I don't like the idea of always running on reserve.

[calamari]

I fill the tank until the gas touches the inside 'neck'.

I usually get 165-172 before going to reserve (CA model), and that's when I ride at 4500-6500rpm (maximum of 7000rpm).
If I do a maximum of 6000rpm, then I get 180 miles before reserve.

Last time I was at 169 before reserve, and the nearest gas station was at 32mi, so I rode on reserve, but then I forgot to refuel, and by the time I remembered, I was at 209 miles or so, and still riding on reserve  :mrgreen:

Good thing I didn't have to push the bike.

[Remy_Marathe]

I fill the tank until the gas touches the inside 'neck'.

I usually get 165-172 before going to reserve (CA model), and that's when I ride at 4500-6500rpm (maximum of 7000rpm).
If I do a maximum of 6000rpm, then I get 180 miles before reserve.

Last time I was at 169 before reserve, and the nearest gas station was at 32mi, so I rode on reserve, but then I forgot to refuel, and by the time I remembered, I was at 209 miles or so, and still riding on reserve  :mrgreen:

Good thing I didn't have to push the bike.

You have a bigger tank.  Later model GS, I'm guessing.
It's beside the point.  I have consistent mileage on mine with the same fill-up routine every time.  It makes it 110 to 130 miles before reserve, riding it hard.  Today it stalled out on me at 70 miles on the tank.

[RedShift]

I'm grasping for something useful to offer, so here's what came to mind.

Noticed the comment about happening while at speed.  Next time it feels like you're fuel starving, pull over and crack open the fuel cap.  This would remove any effect of a blocked vent and gravity should re-establish fuel flow if that's the problem.

Can't hurt (if on a smooth road) and won't cost anything.   :dunno:

[Mountaineer]

Be sure the fuel valve on the bottom of the tank is fully open. If not, you can get the fuel starvation syndrome.
I get 300 miles on a 2001 tank, have never yet had to hit reserve.