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Main Area => General GS500 Discussion => Topic started by: yassensei on November 05, 2006, 06:46:58 PM

Title: Weird occurrence
Post by: yassensei on November 05, 2006, 06:46:58 PM
OK--I was riding around town running errrands and everything seemed to be going OK. I was rolling along at about 35 when I felt a power drop which i thought was a wind gust slowing the bike down. Turns out that the engine was sputtering along. I pulled in the clutch and the engine immediately died.

I rolled to the side of the road (luckily, not a busy road on a Sunday afternoon) and checked it out. Hit the starter button. It turned over, but didn't start. I checked the petcock, thinking that it somehow accidentally got switched, but it was fine. checked the tank (filled yesterday) and it had plenty of gas. Cranked it again--nothing.

OK, now what? i figured I'd try the next best thing and switched the petcock to "PRIme." Let it sit for a few seconds, then hit the starter. Fired right up. Switched petcock back to "On," went on my way. Everything ran perfectly from that point.

I only had to run about three miles after that to get home, so i don't know if this is a problem that might come back. A search of the archives turned up nothing like this.

Any suggestions?

Shawn
Title: Re: Weird occurrence
Post by: scratch on November 05, 2006, 06:53:20 PM
Well, actually, it sounds like the fuel-starvation problem.  (search 'fuel starvation')  Usually, only happens at high-speed/high rpms, fuel supply is too slow and the floatbowls empty quicker than they can fill, and the bike dies.  Switching to Prime helps, and seems to be the only solution, other than riding in Prime all the time (think of it as the Run position, with the On actually as an Off).
Title: Re: Weird occurrence
Post by: scottpA_GS on November 05, 2006, 06:59:42 PM
I agree w/ scratch..  :thumb:


an 05 should behave like that though...  :dunno_white:
Title: Re: Weird occurrence
Post by: dggraphics on November 05, 2006, 08:03:59 PM
My '89 used to do that (before the accident) and I agree, fuel starvation. I think my problem was dirty carbs that weren't allowing the bowls to fill with gas.. also, I always had to run mine on PRIME for some unknown reason (vaccum problem?)

Title: Re: Weird occurrence
Post by: annguyen1981 on November 05, 2006, 08:11:23 PM
Besides dirty carbs, what else could cause this?

My '04 never has a problem like this.
Title: Re: Weird occurrence
Post by: yassensei on November 05, 2006, 08:20:13 PM
Quote from: scratch on November 05, 2006, 06:53:20 PM
Well, actually, it sounds like the fuel-starvation problem.  (search 'fuel starvation')  Usually, only happens at high-speed/high rpms, fuel supply is too slow and the floatbowls empty quicker than they can fill, and the bike dies.  Switching to Prime helps, and seems to be the only solution, other than riding in Prime all the time (think of it as the Run position, with the On actually as an Off).

Silly me! I did my search on "fuel flow problem." No wonder I couldn't find any info!  ;)
Title: Re: Weird occurrence
Post by: scottpA_GS on November 05, 2006, 08:41:29 PM
first check the float height  :thumb: Maybee a rejet would help?
Title: Re: Weird occurrence
Post by: yassensei on November 07, 2006, 10:35:06 PM
Ok...in reading the posts on the fuel starvation problem, I'm noticing two patterns: it seems that for everyone else, the problem occurs at high speed and/or at high revs--which would make sense. When this happened to me, though, it was at 35 mph and at maybe 4500 rpm.

Fuel starvation at high speed makes sense--higher demand for fuel, fed by a limited supply. the lower speed, though,  puzzles me. The bike is new, so the possibility of dirty carb jets doesn't make sense.

The second pattern i see is that there seems to be no other pattern to the problem. Not that that i'm complaining (I don't know anything, so anyone who knows even one thing is way ahead of me), but this is a problem that GS owners have just learned to live with, kind of like exploding Pintos, right?

Oh--and I can't see the tank petcock. I'm assuming it's hidden by the flanges of the edges of the tank and/or the frame. The picture on the board is kind of out of context. I'm guessing that the fuel petcock is at the stern end of the tank? Being the lowest point of the tank, that would make the most sense.

See? I told you I didn't know anything.

Title: Re: Weird occurrence
Post by: MarkusN on November 08, 2006, 02:56:03 AM
Are you sure you weren't low on fuel? Reserve in the GS is about a gallon, looks like an awful lot remaining.

Yep. The tank petcok is at the rear, on the left side. You find it when you follow the fuel lines from the frame mounted petcock. It is hidden by the frame, only when you slightly lift the end of the tank (you have to unbolt it for that) can you see it, but following the fuel lines you can feel it.
Title: Re: Weird occurrence
Post by: yassensei on November 10, 2006, 10:46:06 PM
Quote from: MarkusN on November 08, 2006, 02:56:03 AM
Are you sure you weren't low on fuel? Reserve in the GS is about a gallon, looks like an awful lot remaining.


I had just filled the tank not more than 30 miles earlier. Unless it drinks like a Hummer, it wasn't low on fuel.
Title: Re: Weird occurrence
Post by: ducati_nolan on November 11, 2006, 01:04:50 AM
Do you have a fuel filter? I bet a chunk of dirt or rust could have clogged your carbs temporarally. Before doing anything else, clean the carbs and install a filter. Check your spark plug caps to make sure they're tight too.