2004 750 with rough/wandering idle - help

[chrisx2]

So unfortunately this is my first major problem with this bike. I haven't ridden it in about a month so i suspect carb issues...

It has 11k km. I adjusted valves and synched in the spring to great success. I also changed the air filter and installed iridium plugs. I rode it fairly well up until August where it sat for a while due to a busy schedule.

So i pulled it out and tried to start it today. It would not catch. set the petcock to Pri for a bit and tried a few more times. finally success, but it ran really rough with the rpms wandering up and down....throttle response was slow or lagging with the rpms hanging for a bit before coming down. it wont run without the choke on or it dies. The choke has to be about mid way or it really revs high when full on. After a while, throttle response gradually came back (when blipped) but it hangs ever so slightly upon release. there remains a roughness to the sound of the engine under throttle. All header pipes are hot so no dead cylinders. When in gear (1st) it wants to die unless sufficient gas given and is really sluggish and underpowered. I'm a little apprehensive to go any further than in front of my house and don't want to damage anything, but there's a part of me that feels it just needs a good run.

I put some seafoam in there hoping it would gradually improve, but may not be enough...

Any thoughts? Time for a carb cleaning? Just seems so sudden given it has run so well for so long previously. Perhaps bad gas....the tank is full.

[rexazz2]

throw a bottle of gasline deicer in the tank first
Our Canadian ethanol added fuel causes greif

you could drain the fuel bowls but thats a PIA and I really think the $1 worth of gasline deicer will fix you right up
with the season running out try and burn off that tank and get fuel stabilizer in the next one

[chrisx2]

Thanks Rez...I'll give it a shot.

[akarob]

Yea, there's a small chance you'll be able to clean it out using some additives.

Dry gas, fuel injector cleaner, etc.

Basically, it's the tiny holes in your pilot circuit that are partially (or fully) clogged. You may need to manually clean them out.

With these bikes, when you're not riding them much, it's common. You can prevent (not eliminate) this by using Stabil in the gas and warming the engine every 2 or 3 weeks.

[beachflyer]

i wish the fuel selector had an off position so that you could shut off the fuel and just run the carbs dry. Would be great for storage or when you arent going to ride for a while.

[chrisx2]

i wish the fuel selector had an off position so that you could shut off the fuel and just run the carbs dry. Would be great for storage or when you arent going to ride for a while.

That would be good....but i recall reading somewhere (and someone here may know more...) that the gas and the additives within help maintain the condition of o-rings/gaskets, that if left dry could dry out and cause other issues...sort of damned if you do or don't scenario.

Yea, there's a small chance you'll be able to clean it out using some additives.

Dry gas, fuel injector cleaner, etc.

Basically, it's the tiny holes in your pilot circuit that are partially (or fully) clogged. You may need to manually clean them out.

With these bikes, when you're not riding them much, it's common. You can prevent (not eliminate) this by using Stabil in the gas and warming the engine every 2 or 3 weeks.

Yeah and that's my problem...I do not ride her often enough ...I should keep something in there at all times.

Anyway, I started her up this morning, a little better but she surges with the choke on. Went for a ride down the highway and back ~11 km. Under throttle she seems fine and dandy, but at idle wants too die. Back at home it seemed to idle ok without the choke, but with a little choke she surges again. I think I'll try to siphon that gas out and refresh with a carb cleaner. Then tell the wife I HAVE to go on this really long ride to clean her out ...see ya in few days.

[chrisx2]

Update....it was a vaccume leak. I had added extensions to my carbs for ease of access for synching the carbs. one of the end caps fell off. replaced it with a tighter fitting one and she now purrs as she once did....sucks...just in time for storage...maybe.