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Main Area => General GS500 Discussion => Topic started by: craigs449 on February 29, 2012, 09:36:17 AM

Title: ? about the choke...
Post by: craigs449 on February 29, 2012, 09:36:17 AM
2001 GS 500, 130 main, stock mid, 20 PJ....everything else is stock.

I bought this project cheap as my commuter.  I battled an air leak which I finally solved and put the new jets (thanks Buddha :thumb:) in the bike.  I noticed now when I start the bike cold (or warmed up for that matter) I cannot use the choke or she will stall immedaitely.  This is not that big an issue except it seems odd.  I rode to work yesterday and got the idle adjusted to what I thought was just right (around 14-1600 rpms).  when I left work last night it was 45 degrees F.  Bike would not start with the choke, but did start without it, it idled really low while warming up (around 500-800 rpm's) so I kept the throttle turned a bit to help warm it up.  Once warmed, it settled in to an an idle around 1000-1200 rpm's (which seemed pretty low, but she never stalled even when stopping abruptly).  I rode it all the way home with no stalling issues and she seemed to run fine.  Is this something that I should worry about (the choke), or it that just a quirk with my particular bike? 

-BTW, when I put the carbs back on after rejet, the choke linkage and cable actuated just fine.........

any input/experience would be greatly appreciated.

-Craig
Title: Re: ? about the choke...
Post by: Kijona on February 29, 2012, 09:46:14 AM
Quote from: craigs449 on February 29, 2012, 09:36:17 AM
2001 GS 500, 130 main, stock mid, 20 PJ....everything else is stock.

I bought this project cheap as my commuter.  I battled an air leak which I finally solved and put the new jets (thanks Buddha :thumb:) in the bike.  I noticed now when I start the bike cold (or warmed up for that matter) I cannot use the choke or she will stall immedaitely.  This is not that big an issue except it seems odd.  I rode to work yesterday and got the idle adjusted to what I thought was just right (around 14-1600 rpms).  when I left work last night it was 45 degrees F.  Bike would not start with the choke, but did start without it, it idled really low while warming up (around 500-800 rpm's) so I kept the throttle turned a bit to help warm it up.  Once warmed, it settled in to an an idle around 1000-1200 rpm's (which seemed pretty low, but she never stalled even when stopping abruptly).  I rode it all the way home with no stalling issues and she seemed to run fine.  Is this something that I should worry about (the choke), or it that just a quirk with my particular bike? 

-BTW, when I put the carbs back on after rejet, the choke linkage and cable actuated just fine.........

any input/experience would be greatly appreciated.

-Craig

I noticed something very similar on my 97 after I replaced the pilot jets with larger ones. By the way, you should get the bike as warm as you can (go for a long, somewhat spirited ride) and then adjust the idle. Idle should be at or below 1500 when warm. Keep in mind that, at least in theory, an idle speed that is set too low can cause oil starvation issues. Ideally you don't want the motor to sit below 1000 RPM.

Mine idles at a fart above 1000 when it's cold, and 1350 or so when it's warm. Manual calls for 1100-1200 but the engine doesn't seem to really like it if I set it that low, so I don't.

One other thing I've noticed on my bike is that it refuses to run, at all, regardless of how cold it is, with the choke completely on. Mine seems to enjoy about 20% choke or so.
Title: Re: ? about the choke...
Post by: Kijona on February 29, 2012, 09:54:59 AM
One other thing regarding the choke linkage: the only thing that really matters is that there is some slack in the cable. So long as you can move the lever a little without actually actuating the choke, you're fine.
Title: Re: ? about the choke...
Post by: craigs449 on February 29, 2012, 10:01:05 AM
Thanks for the input.  There is a bit of slack in the cable and it actuates the linkage just fine.  It's almost like this bike is allergic to the choke!  Maybe she was gummed up for so long (sat for a year with old fule.....) that she is now "anti-choke" since I cleaned her up real good.  Good to know that my idle is not as low as I thought.  Just seemed like I should have a higher idle as it takes some throttle to get this "Sherman tank" off the start......
Title: Re: ? about the choke...
Post by: BaltimoreGS on February 29, 2012, 10:07:39 AM
If it is starting in the cold weather without choke you may have the pilot jets too rich. 

-Jessie
Title: Re: ? about the choke...
Post by: craigs449 on February 29, 2012, 07:25:58 PM
Quote from: BaltimoreGS on February 29, 2012, 10:07:39 AM
If it is starting in the cold weather without choke you may have the pilot jets too rich. 

-Jessie


I will fool with the fuel screws and see if that makes any difference with this.  I am at sea level (as are you) with 130 main, stck mid, and 20 pilot.  Fuel screw is currently 3 full turns out from seated.  The stock jetting was 127.5 main, and 17.5 pilot.  I also have the washer under the needle.
Title: Re: ? about the choke...
Post by: Erika on February 29, 2012, 10:44:51 PM
Could it be you are pulling on the throttle too much when you are trying to start 'er up? The choke reduces air, so if you are pulling on the throttle, you may be adding too much gas to the mixture. (flooding, the old-school term) I've noticed it's easy to flood the GS500 , so instead of pulling on the throttle while the choke is on, I move the petcock to Prime and it seems to help. I do pull the throttle 2-3 times at first, but then stop to avoid flooding. Hopefully you have a good battery when it's cold.
Title: Re: ? about the choke...
Post by: Funderb on February 29, 2012, 11:03:54 PM
The choke on these bikes is not what we would call a "choke"
it is an "enrichment system"

It puts a vacuum into the pilot system and pulls more fuel through the pilot system only.

There is no accelerator pump, so pumping the throttle like you would a car or other bike does nothing before the bike is on.

The proper starting procedure is
1. Choke full on
2. Crank until start.
3. wait.

New idle jets will allow starting with 50% choke if cold, but a little extra fuel isnt bad.
There may be a leak to the outside air in the choke sytem, which is doing the opposite of what you want. See if the seals on the enrichment plungers are cracked, worn or missing.