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Main Area => General GS500 Discussion => Topic started by: ColoradoPaul on June 29, 2006, 10:20:19 PM

Title: Little Help
Post by: ColoradoPaul on June 29, 2006, 10:20:19 PM
I am a newbie to motorcycling. I took the MSF class and liked it so much I bought a 1997 GS500E two months ago. Love the bike but have noticed a few problems.

When I ride hard 60mph+ the bike has a tendency to stall. It also has some trouble in the mountains pulling up steep hills. I'm a big guy so It could be just me but  it acts like it is out of gas. I pull off the road and have to restart it. I switch it to the reserve and restart then get to the nearest gas station and pump in a gallon or two. Then I'm up and running again. Anything I should tell the shop to look for? Carbs, rust in the gas tank, something else?

I live in Boulder, Colorado... lots of mountains and rural driving. I like to avoid highways at all cost and sometimes this means running out of pavement. The bike seems to be a bit unsteady on gravel and dirt roads. Anyone have any suggestions... would it help to change tires? Anyone ride their GS on dirt?
Title: Re: Little Help
Post by: pantablo on June 29, 2006, 10:22:14 PM
yours may be a victim of the common fuel starvation problem with these bikes. do a search for that term and you'll come across lots of info on that. It doesnt affect all bikes though because mine for one never had that (it was an 01).

Good luck and welcome! O0
Title: Re: Little Help
Post by: CirclesCenter on June 29, 2006, 10:26:25 PM
Fuel starvation problem, I'm 99.9% certain, i had it, and I just went with the shotgun approach and re-did the whole fuel system.

Try running it on PRIME (petcock settling) on the freeway. Don't leave it on prime when you park though.  :thumb:
Title: Re: Little Help
Post by: trumpetguy on June 29, 2006, 10:30:26 PM
I live in a slightly hilly but VERY windy area.  I sometimes have to downshift to 5th on long hills to avoid the fuel starvation issue. 

The fuel issue is most often a problem with the vacuum activated petcock.  When the GS is pulling in sixth at extreme engine loads, there's not enough vacuum to activate fuel flow (or enough to keep the float bowls full).  Try setting the petcock to PRI (prime).  If that fixes the problem, that's your issue.  Don't leave the bike in PRI when parked, however -- it may flood the float bowls and drain out gas.

As far as dirt or gravel, ANY street-tired bike will be very nervous.  Only a dual sport bike and tire will really be comfortable on dirt and pavement.  If you find yourself having to ride on gravel or dirt, go slower and let the bike have it's head a bit.  It will feel really unstable compared to pavement, and you may lay it down once or twice.  Not good.  I hate it, but sometimes that's the road.
Title: Re: Little Help
Post by: CirclesCenter on June 29, 2006, 10:45:48 PM
Dirt, GS? WHAT THE FRAK???????

Short of making it into a ghetto supermoto I'd have to say no way. (and even then probably say no)

If you're a dirt road kind of guy you are riding the wrong bike. I mean no offense, but if you plan to do anything remotely close to dirt riding even a small percentage of the time you need an enduro.

Enduro's are fun, and generally cheap, but not so fun on the road. You can usually find one buried in a garage that just needs a little work for like 200 - 400 doillars that is not freeway capable, and 800 - 1000 for a freeway bike.

If you are dead set on using the GS in the dirt, for the love of god look into dirt tires, you'll need 'em.
Title: Re: Little Help
Post by: 12thmonkey on June 29, 2006, 10:55:12 PM
i've been having the same problem (fuel starvation). i just completed modifying my petcock to eliminate the vacuum, according to this thread:
http://gstwins.com/gsboard/index.php?topic=19363.0
But, i'll have to wait till tomorrow to take it out for a test ride and see if it helps. From what i hear, it does. Check that out, and do a search for "fuel starvation"...there's tons of info.  Good luck!
Title: Re: Little Help
Post by: pandy on June 30, 2006, 07:08:12 AM
Welcome to the board, ColoradoPaul!  :cheers: My '91 had the fuel starvation issue. Eventually I just ran it on PRI on the highway (always remembering to turn back to ON when off the highway/freeway). You'll find a lot of info on fuel starvation here...it's one of the little quirks of some of our bikes.  :cookoo: :icon_mrgreen:
Title: Re: Little Help
Post by: ColoradoPaul on June 30, 2006, 09:22:53 AM
Thanks for all the help... the Fuel Starvation issue seems to make sense.

As for the dirt issue I already have my sights on a nice KTM in the future but that will have to wait until I've got some more experience riding and some money in the bank.

Thanks again... this is a great board.

Title: Re: Little Help
Post by: blue05twin on June 30, 2006, 10:28:07 AM
Welcome to the board, and you can rejet that should get rid of your fuel startvation issues.  As for tires maybe try some enduro tires?  Someone out there might make some  that will fit the GS rim.
Title: Re: Little Help
Post by: manofthefield on June 30, 2006, 11:22:06 AM
I've always found it fun to ride dirt/gravel roads (obviously not real off roading or trails though)  You just have to slow down and hang loose.  Slow down a lot for turns and watch for obsticles.... the last time I was on a dirt road it was straight and hard packed, so I was going pretty fast, then I nailed a big hole and bottomed out my forks pretty bad.  I was afraid I blew out my fork seals since I hit so hard, but fortunately everything was a-ok :icon_lol:
Title: Re: Little Help
Post by: hmmmnz on June 30, 2006, 12:03:31 PM
i have a friend back home that can get anywhere on his gsxr400 impulse, incredible places, the only thing which could possible let the gs down is the exhaust being the lowest point on the bike. on/off road tyres,(like what goes on the bmw funduros) the only problem you would possibly have is that because the gs wheels are alloy they have no give in them, so if you hit a rock hard you could possibly crack your rim, a spoked rim is always better in off road situations, you might want to think about a new rear shock as well, dont let these nanas tell you how you should ride your bike do what you want :icon_mrgreen:
Title: Re: Little Help
Post by: Jenya on June 30, 2006, 12:22:16 PM
Quote from: 12thmonkey on June 29, 2006, 10:55:12 PM
i've been having the same problem (fuel starvation). i just completed modifying my petcock to eliminate the vacuum, according to this thread:
http://gstwins.com/gsboard/index.php?topic=19363.0
But, i'll have to wait till tomorrow to take it out for a test ride and see if it helps. From what i hear, it does. Check that out, and do a search for "fuel starvation"...there's tons of info.  Good luck!

Hey! Good to hear that the mod is complete. How was it?
Title: Re: Little Help
Post by: scratch on June 30, 2006, 01:44:04 PM
Welcome!

At higher altitudes you shouldn't have to rejet, as there's less oxygen, but maybe adjusting your float levels higher (richer) may help, as well as running in PRIme on the freeway.

As far as pulling you up steep hills, you need to be in a lower gear.

Quote from: ColoradoPaul on June 29, 2006, 10:20:19 PM
The bike seems to be a bit unsteady on gravel and dirt roads.
Sounds normal, but it could be operator error.  Have you ridden a dirtbike before?
Title: Re: Little Help
Post by: blue05twin on June 30, 2006, 02:39:55 PM
Dumb question. . .if you adjust your float bowls higher to be richer.   Wouldn't rejetting to be richer have the same effect?  Sorry if it's an obvious answer but don't understand the difference.
Title: Re: Little Help
Post by: natedawg120 on June 30, 2006, 02:49:22 PM
i could be wrong but i am pretty sure that adjusting the flost bowl levels will have no effect on how rich or lean the bike runs.  Now rejetting the bike will help that or adjusting the jets that are already in there.  Adjusting the float bowls will only effect the amount of gas that sits in the bowl. 
Title: Re: Little Help
Post by: scratch on June 30, 2006, 03:33:29 PM
Adjusting the float level DOES affect fuel ratio, on a more minute basis, it is better used for fine tuning, or when you have no other options.  Changing the jets is a LARGER change, and more noticeable.  Changing the float level affects ALL jets in a carburetor.  While changing jets only affects the range that that jet controls.

My suggestion to him is two-fold:
1. To richen it up (minutely, this is secondary to the fuel starvation problem).
2. Increase the fuel capacity in the floatbowls.  This is help prevent fuel starvation, by making sure there is a large enough amount of fuel (reserve) to draw on.
Title: Re: Little Help
Post by: corndog67 on June 30, 2006, 03:47:18 PM
My 95 does it all the time.  Run wide open in 5th or 6th,  and the carbs run out of gas, even on prime.  There is a mod to put a pingel petcock on it, but I would rather not spend $100 on a Harley part for the little bike.  I think when you run at high speeds, the vacuum isn't opening the petcock all the way.  If I let off a bit, it works ok. 
Title: Re: Little Help
Post by: Jenya on June 30, 2006, 11:12:31 PM
If you are, so understendably,  hesitenet about dropping $100 on the petcock that woudn't even provide you with a RES, then how about spending few bucks and converting your existing petcock to a no vacuum?
http://gstwins.com/gsboard/index.php?topic=19363.0
Title: Re: Little Help
Post by: blue05twin on June 30, 2006, 11:31:47 PM
Ok thanks I understand now.  :thumb: