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Discussion Starter · #1 ·
hello all,

I have a 2009 F4 1078 RR 312 1+1 with 7,400 miles on it. I acquired it less than a year ago with 6,600 miles, and it ran fine when purchased. I have all the service records from the first owner through 2015 (who definitely kept it regularly serviced up to that point), but it appears to have not been ridden much after then.

there are no records of the second owner having done any maintenance, and it was apparently ridden less than 1,000 miles by him. maintenance I have done has included an oil and filter change, new tires, a new battery, a coolant flush/change, and the switch to a Jetprime water pump.

on the way back from a recent hour-long ride, the engine suddenly developed a rough idle and began stalling at stops, requiring constant throttle application to keep running. the engine still runs and pulls smoothly (and strongly) whenever on the throttle and while the bike is in motion... this issue only happens when at a stop and off the throttle.

I siphoned out the gas, put in a fresh gallon, and did a couple short test rides. it's still doing the same thing, so doesn't seem to be from bad gas. there are no error messages on the dash, and I'm not sure where to go from here.

does anyone have any ideas about what may be causing this?

any feedback is much appreciated, thanks!
 

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What was done immediately before the onset of the issue?
 

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2005 F4 AGO 2017 TVL RC
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If you removed the tank the fuel line may be pinched, but it doesn't make sense if it ran good for an hour. Go back and check all of your previous work
 

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Vendor
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You could have a coil breaking down.
Spray some water on each header pipe to see if they are all hot.
It's a starting point to eliminate bad spark.
 

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Discussion Starter · #6 ·
thanks!

a great question- the last thing I did was stop halfway through my ride to gas up at a Chevron, and I did overfill slightly into the filler spout by a few mm. I rode perhaps 25 miles after that, with several stops along the way, and didn't have any trouble until I eventually got off the freeway and was waiting at a light maybe 1/4 mile from home. curious if the slight overfill somehow caused this trouble.

I did not remove the fuel tank, and only the tail section and lower fairings have come off since I have owned it.

I'll try the water on the headers tomorrow!
 

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An overfill on a US spec F4 can get fuel into the carbon cannister in the emissions control system. It lives in the tank and vents at the filler neck. This can affect fueling a bit, but I wouldn't expect stalling. Ed (@esq'z me ) will chime in I am sure....

The BLUE hose is the emissions vapor inlet....

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Old Wing Nut
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Contaminated carbon canister !! Just get rid of it. Probably time to replace those internal hoses, too.
Could also be a fouled spark plug (yes, it happens), but I think you just have the rich mixture from the canister contamination. This can happen with just about any so equipped bike.

Welcome to the family !!! where are you located in these United States?
 

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Discussion Starter · #10 ·
hey thanks everyone for your input! I have had a lot going on the past couple days, so apologize for my delay in response.

I haven't found the time to do anything yet, but having let it sit for a few more days I started it up this morning- it warmed up smoothly until the coolant temperature hit 180, then the idle suddenly began stumbling and it died within seconds. it started back up immediately but then stumbled again and died just seconds later. tried that two more times and the same thing happened- the situation here has clearly not fixed itself with time, ha.

I am definitely gonna get rid of that canister, and will order new hoses and whatever other parts I will need to correctly remove and replace the tank and the fuel pump. it looks like that could have easily been flooded with my accidental overfill... I suppose it would be difficult for that to dry out if that were the case, especially since it is curiously located inside the fuel tank! I will change the plugs out too at the same time.

thank you! I am in Ventura, CA... pretty much summer all the time here- I can technically ride nearly every single day of the year.
 

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Old Wing Nut
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@silentservice703 can hook you up with the internal hose that deteriorates...and other needed items.
 

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Discussion Starter · #12 ·
awesome- very much appreciated. currently researching how to correctly bypass/remove that canister and reroute everything. this discussion you started is great, thanks!

 
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