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Main Area => General GS500 Discussion => Topic started by: OHspartan on May 11, 2011, 06:37:14 PM

Title: Cold starting
Post by: OHspartan on May 11, 2011, 06:37:14 PM
I'm probably being a bit paranoid, but the last two times I've started the bike ('05, 1100mi, 170mi mine) when it's cold, it doesn't fire up the first two or three times(full choke, no throttle). The first bunch of times it would fire right up when perfectly cold- just apply full choke, no throttle, blip the starter and it would start and idle high- 4k rpm. Earlier today I had to give it 1/8 throttle w/ full choke to get it to fire up after it wouldn't start the first three times. Also, I'm either adapting to the bike awfully fast, or it doesn't seem as powerful as it originally was.
This is the first carb'd machine I've owned, so I don't know what to attribute to normal carburetion hiccups, and what to take as an early warning. After the bike warmed up today, it did start with just a blip of the starter with no choke or throttle.

The carbs were rebuilt and the fuel system was flushed 170 miles ago, just before I picked it up. Thanks for any info you may have.
Title: Re: Cold starting
Post by: OHspartan on May 11, 2011, 06:59:24 PM
Forgot to mention- I'll be taking the bike to a dyno in a couple weeks just to check it out. For $5, it's well worth it- then I should know for sure whether it feels slower because I'm used to it, or because other problems are coming up.
Title: Re: Cold starting
Post by: bombshelter13 on May 11, 2011, 08:19:59 PM
I've noticed something similar lately about needing a bit of throttle on cold starts. Very curious to learn what could cause this.
Title: Re: Cold starting
Post by: OHspartan on May 12, 2011, 03:44:13 AM
This morning she went back to being her usual self... full choke, no throttle, started right up and idled high. I guess I have to chalk it up to carb volatility.
Before I got all the way to work this morning though, the bike acted like it ran out of fuel... new topic: http://gstwins.com/gsboard/index.php?topic=56242.0 (http://gstwins.com/gsboard/index.php?topic=56242.0)
Title: Re: Cold starting
Post by: ben2go on May 12, 2011, 06:10:49 AM
Before you start your bike, put the petcock on PRI.After it starts set the petcock to the ON position.When your bike sits, the fuel evaporates out of the carb bowls, through the vents.Your petcock is vacuum operated and can't flow fuel unless the engine is running.A lot of people mod their petcock to eliminate the vacuum operation and get better fuel flow.If you do this,you must remember to shut off the petcock every time you shut off the engine.If you don't,and a carb float hangs open,your engine will be flooded with gas.That requires an oil change before riding again and a carb repair.