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Main Area => General GS500 Discussion => Topic started by: ACDNate on January 25, 2010, 10:21:37 AM

Title: I know this has been beat to death but...
Post by: ACDNate on January 25, 2010, 10:21:37 AM
I'm putting a GS500 back together after sourcing some replacement carbs and picking up new other parts. THe carb routing pic that someone made up is very helpful, and I see what goes where.

The drawing does highlight what a poor design it is though. With the carb feed hose from the petcock to the carbs having to push fuel uphill basically it makes sense that so many have problems with keeping adequate fuel flow.

Ok on to the more specific questions, and enough bitching.

I ordered all new fuel lines to replace the odd balls that were on the bike when I got it. The main feed line seems awefully long. When I place it on the carb and connected it to the petcock and eyeballed the length it seems like it might be a good 3-4" too long.

ANyone who's ordered new fuel lines found them to need trimming???
Title: Re: I know this has been beat to death but...
Post by: tt_four on January 25, 2010, 10:52:31 AM
I replaced my fuel lines, but I bought them by the foot, so I had to cut all of them how long I wanted them. I'll probably replace them again before spring gets here. I just bought the cheapest ones I could find last fall because I wanted to test the bike before winter got here.

I think as long as the end of the hose is below the beginning you shouldn't have any problems with flow, as long as the hose isn't kinked, but yes, a simple petcock and fuel line setup wouldn't have hurt anything.
Title: Re: I know this has been beat to death but...
Post by: ACDNate on January 25, 2010, 11:11:26 AM
Good deal. I went ahead and cut it to the length that worked for me. I really don't get it. I realize the frame design wouldn't allow for a traditional tank mounted petcock as is but this design just sucks.

I rigged up a petcock for a buddies clogged petcock last week with $15 in parts from Oreilly's Auto Parts (thank you Briggs and Stratton for making a simple fuel shut off valve). I may end up doing the same with this bike before it's all said and done.

The carbs are getting fuel for the moment with the lines installed as per the diagram. Fingers crossed that this will work :)

Thanks for the input.
Title: Re: I know this has been beat to death but...
Post by: DoD#i on January 25, 2010, 11:24:07 AM
The stock setup in good shape works fine. The major problem is a failing vacuum diaphragm - people go through all sorts of bother about a part that is easily replaced (though you do have to replace the whole petcock, as there's no diaphragm kit) once every 10-15 years, whatever floats your boat. One instance of forgetting to turn off a manual conversion when a float is sticking can cost a whole lot more to fix if the engine hydrolocks.

I also did mine "by the foot", so cut to suit. I did them considerably longer than the hack job that was on there before, so it's possible to get the tank up a bit for access with the lines still connected - no flow problems at all. I did use good quality thick wall polyurethane fuel hose - the thick wall makes it more difficult to kink.
Title: Re: I know this has been beat to death but...
Post by: ACDNate on January 25, 2010, 11:53:52 AM
Got it all back together and in true Suzuki Air Cooled splendor it fired up after putzing with the idle adjustment. Ran for a little bit then, poof, no more run.

On to diagnosing and I find that I'm not getting fuel to the carbs. When I put gas in the unconnected reserve hose end (the one that goes to the tank) I got fuel flow to the carbs, with the petcock switched to prime. Now I get nothing.

Ok lemme check the tank valve and make sure I didn't turn the flow "on" twice.

Can anyone confirm which direction the open end of the slot, on the tank turn off valve, should be facing when looking at it?

Any other inspiration?
Title: Re: I know this has been beat to death but...
Post by: ACDNate on January 25, 2010, 11:59:50 AM
Ok it seems my retard moment has passed. The open end points down and magically fuel flows. Seemed like the valve would be 180 degree turn to open/close but it looks like it's only 90 degrees...
Title: Re: I know this has been beat to death but...
Post by: ACDNate on January 25, 2010, 12:15:07 PM
It lives!

Ok so I've got a bit of a "hanging throttle". When revved the bike goes up but takes a good bit of time to come back down. That usually means air leak somewhere. Anyone other typical causes for this on these bikes???

I'm gonna try and hunt that down next.

Also it seems i've got a bit of an exhaust leak somewhere. I see the exhaust coming from under the bike but can't for the life of me find the source. It's not consistent enough to trace. It just shows up every now and then, and I find myself scrambling to find it.  :dunno_white:

Once I figure these last couple details out I think she'll be pretty well road worthy, or at the very least parking lot practice worthy. The bike is being put together for my SO, I'll stick with my Bandit 1200 thanks  ;)
Title: Re: I know this has been beat to death but...
Post by: DoD#i on January 25, 2010, 12:23:17 PM
Quote from: ACDNate on January 25, 2010, 12:15:07 PM
Also it seems i've got a bit of an exhaust leak somewhere. I see the exhaust coming from under the bike but can't for the life of me find the source. It's not consistent enough to trace. It just shows up every now and then, and I find myself scrambling to find it. 

Undo 5 bolts and drop the exhaust. Probably a small hole near one of the joints - though if it's that small and intermittent, ignoring until it gets worse is a possible option. But welding it shut will be easier now than later. At that point, might as well grab the masking tape and BBQ black and give it a paint job, too.
Title: Re: I know this has been beat to death but...
Post by: ACDNate on January 25, 2010, 12:28:12 PM
Quote from: DoD#i on January 25, 2010, 12:23:17 PM
Undo 5 bolts and drop the exhaust. Probably a small hole near one of the joints - though if it's that small and intermittent, ignoring until it gets worse is a possible option. But welding it shut will be easier now than later. At that point, might as well grab the masking tape and BBQ black and give it a paint job, too.

Probably the best course of action. Once i figure out the hanging idle I may just do that. Thanks for the input.
Title: Re: I know this has been beat to death but...
Post by: jeremy_nash on January 25, 2010, 01:23:32 PM
you did put the vacuum  line to the petcock back on, and it doesn't have any cracks, right?

oh, and we love the gs500 here, :bs: you dont have to front like your not gonna ride it  :thumb: :thumb:
Title: Re: I know this has been beat to death but...
Post by: kylegod on January 25, 2010, 03:05:13 PM
as for fuel line, I just picked up some clear hose from lowes. Been on for a week or so with no softening or anything...I dont know if its "fuel grade". Is this ok to use ya think?
Title: Re: I know this has been beat to death but...
Post by: DoD#i on January 25, 2010, 03:44:39 PM
For my $3.20 ($4 if also getting the top ventline), no. That's the cost of 4 (or 5) feet of 5/16 inch polyurethane fuel line from CRC2 - shipping extra. Your local dealer may be more or less. Barring a hardware store with a significant small engine focus, most "hardware store clear tubing" is polyvinylchloride and not fuel-rated. Polyurethane is the stuff you want.

From what I have removed of half-baked fuel line substitutes, it's more likely to get brittle than to soften. It's really not that difficult to find actual fuel hose that works for a long time - but various people get away with the wrong stuff, at least until they don't.  Having a fuel line shatter probably won't turn the bike into a fireball outside the movies, but would kinda ruin your day, your left pantleg, and your left boot. Before it reaches that point, you may find that you remove the tank to do something like adjust the valves, put the tank back on, and have a leak because the ends of the hose are too stiff to seal anymore.
Title: Re: I know this has been beat to death but...
Post by: ACDNate on January 25, 2010, 03:51:29 PM
Quote from: jeremy_nash on January 25, 2010, 01:23:32 PM
you did put the vacuum  line to the petcock back on, and it doesn't have any cracks, right?

oh, and we love the gs500 here, :bs: you dont have to front like your not gonna ride it  :thumb: :thumb:

Yepper, vacuum line is new and is back on. Once I got the tank valve opened correctly it's getting fuel.

No fronting, I'll be riding it periodically till the SO starts venturing out more often with it, to keep things moving. Don't get me wrong the GS500 is a great lightweight bike, but for my size, 6'3" 240lbs, the suspension is way way too soft. The suspension is setup pretty well for her weight though, so I'll leave it alone. I could be a bit spoiled with my Bandit, I put a good bit of time and a few bucks into upgrading and setting up the suspension for my weight and riding style.  It's almost as couch like as a Goldwing :)

Kylegod, I'd advise strongly against the clear stuff, that's what I removed from the bike. It was ridiculously brittle from the fuel and just isn't made for it. Most auto parts stores have hose by the foot for little to nothing. You'll be better off in the long run...
Title: Re: I know this has been beat to death but...
Post by: johnny ro on January 25, 2010, 07:47:21 PM
maybe leave a bit of slack to accommodate inline filter?

I'm a weenie, just bought OEM fuel lines from bikebandit. My tank is pristine.  I didn't like the 10-8 mm drop in size for one of the lines. 

My 2001 SV tank swung up on hinge, I forget, think hinge is in front. Just pop up put the rod in place. GS should have that.
Title: Re: I know this has been beat to death but...
Post by: PachmanP on January 26, 2010, 07:05:33 PM
Quote from: ACDNate on January 25, 2010, 03:51:29 PM
No fronting, I'll be riding it periodically till the SO starts venturing out more often with it, to keep things moving. Don't get me wrong the GS500 is a great lightweight bike, but for my size, 6'3" 240lbs, the suspension is way way too soft. The suspension is setup pretty well for her weight though, so I'll leave it alone. I could be a bit spoiled with my Bandit, I put a good bit of time and a few bucks into upgrading and setting up the suspension for my weight and riding style.  It's almost as couch like as a Goldwing :)

Ok so who wants to set up a pool for when the GS has upgraded front springs and an R6 shock?   :icon_twisted:
Title: Re: I know this has been beat to death but...
Post by: ACDNate on January 26, 2010, 07:09:59 PM
 :laugh: :laugh: :laugh: :laugh:

Now if she decided she wanted something different, we probably couldn't get much from it, I mean she only paid $800 for it, then maybe I might have a little fun with it. Of course the purple paint would have to go first and foremost!

Ok a little follow up on the wandering revs. I pulled the tank tonight to track down the leak. Had a buddy help me out by holding the funnel of fuel into the fuel line (really gotta buy a small tank with a valve). Well magically the odd wandering revs couldn't be re-created. Took some head scratching but I figured out that the little bit of gas leftover in the tank must have some water or something funky in it. As soon as I put the tank on it started up again. Once I drained the gas and replaced it with fresh gas it no longer did anything funny.

All is well again  :thumb: