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Main Area => General GS500 Discussion => Topic started by: jestercinti on October 31, 2012, 07:53:13 AM

Title: GS500 starting below 40* F
Post by: jestercinti on October 31, 2012, 07:53:13 AM
So I have noticed that when starting the GS500 in the morning when it is very cold (Below 40*F/5*C), it cranks OK, but the choke acts funny.

Normally, when the choke is all the way on, the RPMs will climb to 3000-4000 pretty quick when I 'blip' the throttle.  When below 40*F, RPMs hover between 1500-2000 and stay there even when 'blipped'.  It takes a lot longer to warm up too.  My jetting is 20/65/142.5 2.5 turns, no washers.  Lunchbox, stock exhaust.  Engine is in good tune including the valves, air cleaner, and plugs.

It acted this way when bone stock too.  I use Iridium plugs.

Is this normal for air cooled engines in the Winter time?  I have read about gasoline mixtures in internal combustion engines when cold being a challenge.
Title: Re: GS500 starting below 40* F
Post by: Funderb on October 31, 2012, 09:21:25 AM
 wait, are you making a funny?
Title: Re: GS500 starting below 40* F
Post by: jestercinti on October 31, 2012, 09:56:37 AM
Nope, although it looks like I am funning in some way I guess.   :dunno_black:

EDIT:  After reading the post again, this looks like a question and answer session from Mr. Obvious.  I guess I'll chalk it up to a blond moment there.   :cookoo:  I'll go back to riding in the cold now....
Title: Re: GS500 starting below 40* F
Post by: stokes776 on October 31, 2012, 10:39:54 AM
I think you are just wanting to make sure what you are seeing is normal. I think it is, but would appreciate an answer from a veteran as well, since I would like to know as well!
Title: Re: GS500 starting below 40* F
Post by: Funderb on October 31, 2012, 11:36:33 AM
hahaha, you've been around here long enough, i assumed you were just kidding.

in seriousness, bring the idle mix screws out to 3 turns for very cold (sub-40) riding. It may actually help a lot.

The flashpoint of gasoline is -45deg according to wiki, so weather in the 30s is probably enough to limit the vaporization enough to lean out the mix enough to make it hard to start. Opening up the mix screw lets in more gas vapor to the mix, and should richen the mix up for the cold times. I keep a little straight slot bit in my riding jacket in case i want to futz with the mix.
Title: Re: GS500 starting below 40* F
Post by: jestercinti on October 31, 2012, 11:44:36 AM
Yep, been around a while...but lately, I HTFU and ride when it's cold.

I used to not ride when it was below 50  :cookoo:.  Now, I lowered the threshold to just below freezing provided no water, snow, slush, etc.

My bike gets Pi$$y when it's under 40.  Rightfully so I guess, and now I know.