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Main Area => General GS500 Discussion => Topic started by: jakkyl on March 16, 2006, 10:04:40 AM

Title: reserve
Post by: jakkyl on March 16, 2006, 10:04:40 AM
Ok, i rejetted a while ago and now my reserve isn't working or something...
I was riding to class today and ran out of gas on the freeway, i switched to reserve and it was still sputtering till it finally cut off.  luckily i was at my exit when it happened, but i had to push it to the nearest gas station...  Anyway, i checked inside the tank and it was pretty dry.  I know usually when i fill up after running reserve there is still a fair amount of gas visible.

I don't know how the reserve works, but is there a way i might have bypassed it and the main is using it all?  or maybe i have the hoses switched and ive been running off the reserve?  I think those two possiblitlies might be the same thing, but...  Is that my problem?   I also only got about 205 miles on the tank... kinda low, but I had been running it pretty hard.

i rejetted with this
20 pilot
132.5 main
62.5 mid

I think I might need to up in the main too
Title: Re: reserve
Post by: Egaeus on March 16, 2006, 10:09:18 AM
Switching main and reserve could definitely cause that problem. 
Title: Re: reserve
Post by: My Name Is Dave on March 16, 2006, 01:25:51 PM
+1. I never really understood how reserve and main worked until I was rebuilding my scooter. In the process, I had to derust the tank. When I was looking inside of it, I saw for the first time what is going on in there.

There are 2 stems coming from the bottom of your tank. These go to the petcock, which selects which line will supply fuel to the carbs. They look normal on the outside, but look inside the tank and there's a difference. One has a tube that sticks up into the tank, and the other is just a hole that's flush with the bottom of the tank. The one with the tube is the main. This supplies fuel until the gas level drops below a certain point, at which time the tube is higher than the gas and thus is only pulling in air. Your bike sputters and tries to die, as the only fuel left is that in the float bowls. Switch the knob on the petcock to reserve, and now the fuel comes from the bottom of the tank and will run until the tank is empty, at which point you're SOL unless a gas station is near.

So if you switch the lines, you're gonna be running off the reserve line the whole time. It's not a huge deal, of course until something like what happened to you happens. Then...it's kind of a big deal.

I hope that sorta helps.

Dave

Quote from: Egaeus on March 16, 2006, 10:09:18 AM
Switching main and reserve could definitely cause that problem. 
Title: Re: reserve
Post by: natedawg120 on March 16, 2006, 01:47:45 PM
yeah the pretty much covered it, you probably have you res and main fuel lines switched around.
Title: Re: reserve
Post by: jakkyl on March 16, 2006, 02:48:25 PM
that's pretty much how i figured it worked, thanks for the clarification.

Ill fix it up when I get my new main jet, until then ill just have to be careful

thanks guys
Title: Re: reserve
Post by: jakkyl on March 16, 2006, 02:50:36 PM
any ideas on what main to get?   I get sputtering/hesitation around 6-7.5k rpm
none after or before that range

...or is that an air screw problem?
Title: Re: reserve
Post by: scratch on March 16, 2006, 03:16:21 PM
Did you adjust the needle?  Move the clip down one notch, which effectively raises the needle.
Title: Re: reserve
Post by: John Bates on March 16, 2006, 03:18:20 PM
Quote from: jakkyl on March 16, 2006, 02:48:25 PM
........................
Ill fix it up when I get my new main jet, until then ill just have to be careful

thanks guys

Just run in the reserve position.  Then when the fuel level reaches the reserve zone switch to run.

The only difference is that you will not have the prime available when low on fuel.

:cheers:
Title: Re: reserve
Post by: jakkyl on March 16, 2006, 08:10:16 PM
Quote from: scratch on March 16, 2006, 03:16:21 PM
Did you adjust the needle?  Move the clip down one notch, which effectively raises the needle.

I didnt know you were supposed to adjust the needle for 05's   ??
:dunno_white:
Title: Re: reserve
Post by: jakkyl on March 26, 2006, 07:41:17 PM
any ideas on my hesistation?     I don 't wanna buy new jets and all that if it's not the problem...   :icon_confused:
Title: Re: reserve
Post by: annguyen1981 on March 26, 2006, 07:47:28 PM
Quote from: John Bates on March 16, 2006, 03:18:20 PM
Just run in the reserve position.  Then when the fuel level reaches the reserve zone switch to run.

The only difference is that you will not have the prime available when low on fuel.

:cheers:

If the hoses are switched, you run the bike on RESERVE, but when fuel is not getting to the engine, switching to the RUN position will make it worse.

Jak - unfortunately, I don't have enough knowledge about jets
Title: Re: reserve
Post by: My Name Is Dave on March 27, 2006, 11:41:02 AM
Quote from: annguyen1981 on March 26, 2006, 07:47:28 PM
Quote from: John Bates on March 16, 2006, 03:18:20 PM
Just run in the reserve position.  Then when the fuel level reaches the reserve zone switch to run.

The only difference is that you will not have the prime available when low on fuel.

:cheers:

If the hoses are switched, you run the bike on RESERVE, but when fuel is not getting to the engine, switching to the RUN position will make it worse.


I think you have that backwards. In a normal situation with the hoses correctly attached, you can run with the petcock turned to RESERVE, but if you get low on fuel and switch to RUN you will be drawing from the taller tube in the tank, AKA you're gonna be drawing nothing but air into the carbs and you'll die.

However, that's not the case with the hoses switched. If you turn the petcock to RESERVE with the hoses switched, you'll draw from the MAIN tube in the tank, which is what you want. And then when you switch the petcock to RUN, you'll be drawing from the RESERVE tube in the tank, again correct.

So it depends on how you have your hoses hooked up. But if he had his hoses switched, he'd want to ride normally in RESERVE and then when he is low on gas and sputters he'll want to switch to RUN until he refuels.

Dave
Title: Re: reserve
Post by: jakkyl on April 06, 2006, 11:12:39 PM
wow, so, i guess running off reserve with the lines switched didnt work like I figured.   Ran out of gas again today on my way to class and had to push the bike up a hill just off an exit ramp.   So i had cars flying by me all the way up....   :mad: :2guns:   Could it be something other than switched hoses or would that not work anyway?
Title: Re: reserve
Post by: MarkusN on April 07, 2006, 12:25:43 AM
I think you had a problem priming it. With the hoses reversed PRI is fed from the tank pickup higher up. As soon as you run out of main, PRI doesn't get any fuel to fill your carb bowls.

Try leaning it over to the left while priming next time.

My guess is that you'd have been fine had you switched over to ON as soon as it started sputtering.
Title: Re: reserve
Post by: jgxtra on April 07, 2006, 01:28:34 AM
I have been having some similar problems.  I am still trying to figure out what is going on.  I am sure with all he different owners of the bike I bought there could be afew thing switched around.  I posted a discussion about my new to me GS.  If anything comes up that could help me let me know. I'll do the same. Good luck, and hope you don't run out of gas again.  I was on my first ride the other day with a buddy who luckly works at the Honda, Yamaha, Suzuki shop as a service advisor. I would have had a long push home up a steep hill if he wasn't there to get the bike running again.  Cool thing was he was riding his new Super Moto thae he let me ride back, it was different, but fun.

Later