Question on reserve and spark plug gapping

[Kaizer]

I am curious if anyone has had this problem. I seem to run "out of gas" and have to switch to reserve at a ridiculous 118-130 miles.  When I fill up, there are still TWO gallons left in the tank? How is that possible? It is still crappy getting 36 mpg, but where could the problem be? Also, what regap do I need on NGK spark plugs? I am going to get new ones since I think my fuel efficiency is not so good and I have tried everything else. Let me know. thanks.

[Dan02GS]

Hey I havent been around much too busy. I usually have to switch over to RES at 170-180 miles. I think I remember hearing that the tube inside the tank maybe be set differently on differrent GS's so that maybe why this issue is never really resolved. As for the plugs I use the regular old NGK DPR8EA9 plug not iridium plugs, and the plugs are usually pregaped. I think it was something like .035. Remember to be careful when snuggnig the plug go by hand til tight then a 1/4 turn or less and recheck later. Hao ba, zaijian.

[utgunslinger13]

According to my clymers manual for the 89-02 models spark plug gap is 0.7-0.8mm (0.028-0.031 in.).

[beRto]

How are you filling the tank in the first place? It can be tricky to get a full tank; you need to put the bike on the centrestand and fill it slowly. Give it time for air pockets to work themselves out. Some people even rock the bike slowly.

Make sure the fuel gets up to the neck filler (unless you're about to park the bike, in which case you want to leave some room to allow for fuel expansion if the temperature rises).

[Kaizer]

yep, i fill up to the neck. fast at first, then slow and let it dribble in. thanks, i will try to be more careful.

[yamahonkawazuki]

the bike will run out of gas long before the tank dries ( usually around a gallon or less left) hte bike is gravity fed. so unless a gs has a major leak in the tank, you would never see a dry tank

[pbureau69]

mileage on a full tank depends on how you drive and mods you have, and what year your riding.

I ride an 05 with only a K.N filter in the box as engine mod and I can got easy 200-220 before I refill and usually sit on center stand, to bottom edge of refill neck and is ~ 3.8-4.1 gallons... and I havent used the RES, then again I run on PRI all the time

cheers.

[ohgood]

I am curious if anyone has had this problem. I seem to run "out of gas" and have to switch to reserve at a ridiculous 118-130 miles.  When I fill up, there are still TWO gallons left in the tank? How is that possible? It is still crappy getting 36 mpg, but where could the problem be? Also, what regap do I need on NGK spark plugs? I am going to get new ones since I think my fuel efficiency is not so good and I have tried everything else. Let me know. thanks.

Take a look at how the tank's petcock is designed. It cannot empty the tank. Well, not without slinging the bike around a few times to slosh the gas down the tubes.

As far as filling the tank, you can do the rock n rock method to get it up a little past the filler neck. I usually just blast it in there until it touches the neck, then consider it good for 130-150 miles. I don't like to run the tank that low though, because then you get into issues with condensation if it sits overnight near empty.

[Kaizer]

condensation? oh crap. my bike sits almost empty for weeks. I use one tank of gas per month. Is that bad for the bike? Should I add something to my fuel then? Thanks and let me know.

[DoD#i]

It is still crappy getting 36 mpg, but where could the problem be? Also, what regap do I need on NGK spark plugs? I am going to get new ones since I think my fuel efficiency is not so good and I have tried everything else.

Have you checked the valve clearances? Thread running a while ago about low milage ended when the original poster fixed a massively out of tolerance exhaust valve, as best I recall.

As for condensation, the best thing is to leave the bike sitting full, or near full - so add gas. You can also add drygas, same as for cars - basically dry methyl or isopropyl alcohol, which mixes with any trapped water. But if you simply switch to leaving the tank mostly full most of the time, it will work out eventually.

[Kaizer]

hmm, valves were done before I bought the bike, year and half ago. I have only put about 3000 miles on it. I don't really have a chance to fill up much and mixing alcohol in my tank just sounds like a really bad idea. Maybe some fuel stabilizer might help or sea foam? Not sure.

[Dan02GS]

Almost every fill up I like to put a cap full of seafoam in my tank. Sometimes I have my bike sit for the week until I can ride on the weekend, about 160 miles to LA and back almost every weekend. I think the seafoam is a great idea, as for other fuel stabilizers am not sure, I trust seafoam.