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Main Area => General GS500 Discussion => Topic started by: jakeoster on October 12, 2015, 05:10:34 PM

Title: Bad batch of gas?
Post by: jakeoster on October 12, 2015, 05:10:34 PM
Recently a starting issue has cropped up. Today it got a little worrying because for the first time I wasn't fully sure it would start :icon_exclaim: I had the choke fully open and it would barely keep it going at 1500rpm. After sometime it shot up towards 4K like normal. Usually it heads towards 4K pretty quickly after starting. Earlier after cruising on the freeway at about 80mph in 90 degree weather I parked it. After walking out about an hour later I had to crank on the starter, choke fully open, while giving it incremental twists of the throttle to get it to fire.

Seems to be a fuel related issue. The bike runs perfectly fine once it starts, no issues and idles fine right at 1200 rpms. Before I go into the carbs I figured I'd see if this might just be something as simple as a bad batch of fuel.

I've shimmed the valves and the plugs look good.

Title: Re: Bad batch of gas?
Post by: akapellen17 on October 12, 2015, 05:24:38 PM
Best option is to just drain the tank and start with some fresh gas. If the problem persists, then there's additional issues.
Title: Re: Bad batch of gas?
Post by: jakeoster on October 12, 2015, 05:29:28 PM
Ok, thanks.

Kind of weird, never got a bad batch before. To clarify I ride it pretty much everyday. Filled up the tank only a few days ago. Maybe I should try going to Shell or something.
Title: Re: Bad batch of gas?
Post by: akapellen17 on October 12, 2015, 05:32:32 PM
Didn't realize that you just got it a couple days ago. I thought maybe it was old gas! Old gas is never good!
Title: Re: Bad batch of gas?
Post by: akapellen17 on October 12, 2015, 05:36:10 PM
Hmm... Its weird that it only happens when it starts. Someone else is going to have to chime in here. Is there anything that happened? Or did it just randomly start happening after you filled up with that gas?
Title: Re: Bad batch of gas?
Post by: jakeoster on October 12, 2015, 05:41:55 PM
Pretty much. The one thing I did do was after running 91 octane since buying it, I read the owners manual and discovered it only needs 87. With about 150 miles on the odometer, I filled it up with the 87 I'm running now. Enter: problems. Lol

The funny thing is I hadn't rode it in a day and it fired up beautifully this morning. Only after leaving work and at the grocery store did it crop up.
Title: Re: Bad batch of gas?
Post by: EdChen on October 12, 2015, 06:23:48 PM
Draining the gas is an easy check, but I'm of the opinion that it's pretty unlikely to get a bad batch of gas, unless you went to a very rural station that gets little to no traffic. Maybe you can go to a busy gas station and top if off to see if it changes?
Title: Re: Bad batch of gas?
Post by: akapellen17 on October 12, 2015, 06:23:58 PM
When I first got my bike I put 87 into it and it started having issues for me (this was my first bike way back when I was 16) so I didn't know any better. I now put 91 in and haven't had a problem since.
Title: Re: Bad batch of gas?
Post by: akapellen17 on October 12, 2015, 06:25:09 PM
I'm sorry I meant 93 octane!  :technical:
Title: Re: Bad batch of gas?
Post by: jakeoster on October 12, 2015, 09:01:25 PM
Started it without too much fuss and rode it home, no issues along the way. This ones got me sort of stumped :cookoo:
Title: Re: Bad batch of gas?
Post by: barry905 on October 12, 2015, 10:07:26 PM
Before starting on the carbs (or any other extensive/expensive repairs) I would put some fresh fuel in there. You never know what you put in hte lst time you filled it - the last of the underground tank, some diesel that someone had dumped in the tank - it could be anything. So I would put some fresh gas in there as my first test.

Good luck.

Title: Re: Bad batch of gas?
Post by: jakeoster on October 13, 2015, 05:42:45 AM
Ok, I'm going to fill it up today with gas from a different station.

It seems to hinge on the weather. This morning it was about 68F and it started and ran amazingly well.

Problems seem to occur when the ambient temp is 90F or above with humidity. I also do most of my riding at or near sea level of that has any effect.