Trouble Starting

[Leut_Dan]

I have a 2006 GS500F. I have just replaced the battery because the old one died on me, and now my bike has trouble starting. The battery is fresh, so I don't think thats the issue. I didn't have any starting issues with the old battery (until it died of course).

I'll close the choke and hit the ignition, giving it a little gas at the same time (like I usually do). The engine will start, go to about 4000 RPM's and then just die, regardless of me being on the throttle. I'll try again a couple of times and nothing will happen, just the starter trying to get it to go. After about 6 or 7 tries, and waiting about a min b/w tries, It'll start up like normal (with the choke closed) and then it will be fine.
If the bike is still warm from before when I start it, it starts no problem.

Also, when I replaced the battery, I had to remove the vent tube because it was stuck on the old one. With the new battery, i re-inserted the tube where it was before. I mention this because I'm thinking maybe I hit something when I put the tube back in, I'm not sure. Thats the only thing that I could think of that changed other than getting the new battery (which was the exact same make and model of the old one).

I dont know what the problem is, once the bike is running it seems to be normal. It almost seems like the bike sounds louder now too, but that could very well just be me.

The weather has been cold lately (roughly 50F), but I had no trouble starting it in the cold before.
Anyone have any ideas as to what the issue might be? Or should I just take it in and get it checked out?

[bigfatcat]

Maybe not letting it 'prime' long enough before start ? = carb bowls almost empty.

[bassmechanicsz]

Have you tried starting it with the choke open?

[Leut_Dan]

I looked around on the net and someone suggested that the tank might not be venting properly. I tried starting the bike with the tank lid open and it seemed to start up just fine. I went through all the vent hoses and made sure none of them were squished or kinked.

Does this seem like a genuine reason for the bike not starting before, or is it just a coincidence?

[Kijona]

Not enough fuel getting to the motor, simply put. Since you said that it starts fine with the tank open - you've got vent issues. Perhaps a pinched line somewhere. Something is contracting to the point of not letting fuel/air in/out, and when it warms up it's expanding allowing passage of fuel and/or air properly.

That's just my take on it though.

As far as sounding louder, it's normal for a motor with its choke engaged to sound louder - it changes the flow of air. As for the overall reason it revs without throttle input, that's because it's leaning out and the mixture is changing. It has adequate fuel...then not enough and that causes a lean mixture which will make the engine run faster at any given throttle position including idle.

My advice is to check and recheck every single piece of fuel line and hose for kinks, holes, and the like. It's probably somewhere you wouldn't expect. It may also be something entirely unrelated. That's how these things go.

Hope this helps, be careful!

-Kij

[bigfatcat]

I looked around on the net and someone suggested that the tank might not be venting properly. I tried starting the bike with the tank lid open and it seemed to start up just fine. I went through all the vent hoses and made sure none of them were squished or kinked.

Does this seem like a genuine reason for the bike not starting before, or is it just a coincidence?

I think the fuel tank vent is integral to the gas cap - no hoses - and probably some kinda plastic valve too (to prevent spillage after a tipover).