Fuel range went from over 200 miles per tank to about 150

[Gary856]

I've been riding my GS500 for 7,000 miles and I had always been able to get 200-220 miles a tank, never hit reserve, and put in about 4 gallons of gas, for an average of about 55 mpg. About 2 months ago I had the carb adjusted at a shop to fix a bad low-speed hesitation/stumbling, and now it runs real smooth right off idle and warms up very quickly. However, since the carb adjustment, I would run out of gas around 150 miles, and could only put in a little over 3 gallons of gas to fill it up. I went thru 2 tanks like that. The gas mileage is still about 50 mpg, but it seems like I've lost almost 1 gallon of "use" of what I have in the tank. When I ran dry after 150 miles, the bike would start normally after I switch to reserve, so this doesn't seem caused by wrong hose connection... I spoke with the shop and they had no idea how this could be, and I'll be back there this Saturday for them to check it out.

Can you think of anything obvious that would make the engine die with over a gallon of gas in the tank?

[romulux]

Perhaps the hoses were swapped leading to the petcock so that you were really always using the reserve.

[Gary856]

Perhaps the hoses were swapped leading to the petcock so that you were really always using the reserve.

If that were the case then I should get more range, not less, right? Like I said, after the bike died (with only about 150 miles after a fill up), it would start and run when I switched to reserve, so the reserve seems to still be the reserve. 

[romulux]

No, I mean maybe you had them swapped before and never actually ran out completely.  Your first post said you never hit reserve and you filled about 4 gallons.

That seems to me like you always had it turned on reserve and the shop fixed it by putting the hoses where they're supposed to be.  Now, you're hitting reserve where you should be, at 150 miles.

[Gary856]

I see what you're saying and that makes sense theoretically. However, Wikipedia shows GS (mine is an '01) from '01 has a 5.3 gallon tank, so running out (or hitting reserve) at just over 3 gallons doesn't seem right. How many gallons of gas can you put in after hitting reserve?

[romulux]

I have an 01, too, and I refuel at about 150 miles.  I put in between 2.5 and 3.5 gallons, depending on when I stop.  I never ride on reserve.

[Gary856]

Thanks, romulux. If you were right (that the hoses were connected backward in the first place so I always "was" on reserve), it's a little mind boggling for me to think that all this time I relied on a safety net that wasn't there. 

[jeremy_nash]

i'v never relied on the reserve myself, but instead fill up around 100 to 150 miles

[Eklipse]

More ethanol, less gasoline? It's a conspiracy.

[the mole]

Romulux's answer is the only rational explanation (if you leave out aliens messing with your bike). Save the cost of taking it back to the shop!

[tt_four]

That sounds like a good explanation to me. The only other thing I can think of is that one of their mechanics accidentally dropped a gallon's worth of wrenches in your tank and it's one less gallon you can fit in your tank, or they knocked a massive 1 gallon dent in the bottom of your tank. I guess just to screw with you they could've extended the "on" spout up a couple inches higher inside the tank. Haha, lets hope it was the hoses.

Hoses are very likely considering one of the hose diagrams in the manual was backwards. 

You're real lucky you never ran out! I did that the other day. 43 miles into my first ride in a couple years and I realize that I still had the bike on PRI, after I forgot that I only put about a gallon in the tank so it wouldn't be as heavy when I kept pulling it off the bike. It'll get filled and left on "ON" before I take off again next time!

Do you remember what order the hoses were connected before? You could take a peak under there to see if it's opposite of what you had.

[gsJack]

The 01-02 bikes are the only ones where the fuel lines cross each other coming from the tank to the selector valve.  After having my tank off once and getting going again I ran out of gas very quickly but found I could get home by turning to reserve.  Discovered the crossed fuel lines were pinched together just behind the clutch cable shutting off main flow but not quite shutting off the reserve.  Make sure your lines are connected right and not being pinched anywhere.



Also my 02 with the 5.3 gallon tank goes to reserve at 3.5 gallons used consistently.  That's about 210-220 miles in the summer and I switch to reserve and go to about 240 miles and put in 4 gallons for an overall average of 60 mpg.

[Gary856]

Thanks everyone, and gsJack for the hose diagram. I don't do anywork on the bike myself - I let the shops do it - so I have no idea how the hoses were connected before/after. I'll follow the diagram and take a peek, but from your feedback, especially from gsJack on hitting reserve at 3.5 gallon used, it seems like my bike is now "normal". Well, that's a LOT of reserve. It was nice to have 200 miles between fill ups. I may experiment w/ how far I can go now with reserve; if with reserve I could consistently go over 200 miles like before then I'm good.

[jon619]

My mechanic told me that after he installed my inline fuel filter, I may or may not lose miles between filling up. Something with the pressure differences. I think that's what he said anyway. Maybe a clogged fuel filter?

[commuterdude]

If you are getting noticeably better carb performance maybe they richened it up quite a bit.   Don't know if this would knock you out to the tune of 50 mpg, but it's a thought.   FWIW I go on reserve at about 130 miles.   Maybe I need to check my wheel bearings or something lol...

[CheetoPet]

A previous owner of my bike decided to route the reserve on my tank directly to the main on the petcock then cap off the leftovers.   Can't say its functionally ever been much of an issue tho I do question their judgment.

[Anaconda]

sadly i range about 100 miles before i have to go on reserve..... btw, have anyone experienced having to switch to reserve while riding on the freeways?  I haven't experienced that yet, but I'm curious if you guys have.

[mister]

How about while overtaking a truck?

Half way along the bike just died. I knew I was close but... quickly switched and all was well. 

Of course, the first time on the GS I hit reserve I went to reach for where it was on my previous bike. Not being able to find it in the blind like this I was forced to pull over. That was on the highway.

Michael

[Jabilli]

I would imagine that you would lose a few miles per fill-up if they enriched the fuel mixture, but I wouldn't think it would change it any more than a handful at most....Fun thought- if you buy a large enough inline fuel filter, that effectively adds that much more fuel you can carry...hmm.. Kicking around numbers for fun, a filter that holds about 6 Oz of fuel is slightly over 1/21 of a gallon, so thats about close to 3 miles...Not a whole lot but if ya wanna really have at it there are the larger filters designed for cars- maybe the size of a soda can- added 6 miles or so.

My little 50cc moped I had a few years back, I forgot to plug the fuel line back in to the petcock so it was running just off the filter (maybe the size of a spool of thread), It went quite a ways before I sputtered out of fuel.

[007brendan]

I nearly always ride on Prime, which pulls from the reserve spout, right?  On and Reserve on my petcock are junk.  Well, I don't know about Reserve, I don't really use it.  But the On position, guaranteed if I wring the throttle out onto the highway, it'll start stumbling eventually.  I'd really just like to replace the whole fuel line assembly with something much simpler.  I'd be cool with just an on/off valve.  Not really sure how I should go about doing that yet, though.