Engine won't idle after filling up gas tank

[Butcher]

I'm thinking I'm dealing with vapor lock,  except if I hold the throttle open for a few seconds after it starts then let go it will then idle fine.  Any ideas or thoughts?

[BBB]

Does it only do this if the bike is half-warm? For example, a short ride from cold start, to pick up fuel? If so, then your issue is just about that half-warm phase and won’t happen with a cold or fully hot start. Mine does it often and just needs a bit of throttle and is then fine.

[Butcher]

Hello BBB, it just happens when the engine is hot and it's hot out. If it sits for a few minutes.  Anything more than ten minutes it will start and idle fine. I have tried different gas stations as well. Do these bikes have an idle valve?

[BBB]

They have a set of pipes and a solenoid on top of the engine that bleed extra air into the mix to reduce emissions (called the AIS). I’m not sure if it would be related to your problem though. How old is the bike?

[Butcher]

Its a 2015.

[skipperT]

9 hours ago, BBB said:

They have a set of pipes and a solenoid on top of the engine that bleed extra air into the mix to reduce emissions (called the AIS). I’m not sure if it would be related to your problem though. How old is the bike?

This system only works on deceleration.

-Skip

[skipperT]

11 hours ago, Butcher said:

Hello BBB, it just happens when the engine is hot and it's hot out. If it sits for a few minutes.  Anything more than ten minutes it will start and idle fine. I have tried different gas stations as well. Do these bikes have an idle valve?

Butcher - no idle “valve” that is user controlled. YCC-T systems are an ECM controlled throttle plate position, depending on rpm, engine and air temp, and atmospheric pressure. It will idle the engine as it seems necessary and goes into “closed loop” mode where it also takes O2 sensor measurements into the formula for mixture control at coolant temps greater than 140 degrees F. 

I have a 2015 and have experienced the same thing sporadically over the years, my bike has 49k km on it now. 

I don’t think a fix has been found that works 100% of the time however here are some things to verify:

throttle cable freeplay 3-5mm

battery condition over 12.5v DC

flashed or not? Stock engine/exhaust? Mileage on bike, valves adjusted yet?

fuel octane used?

also always wait 2-4 seconds after key on/rh handlebar switch on before cranking. This gives the fuel pump time to pressurize the system. 

Sometimes I hit the start button quickly enough to “burb” the engine over, pause for a pregnant second, then crank until it starts. Seems to work for me, even when hot. 

Report back if you get a chance  

-Skip 

[Torbeach]

Check the over flow tube to make sure it is not blocked causing a partial vapour lock. There might be some dirt on it where it come out the bottom of the bike. 

[Butcher]

Skip,  so i filled up the bike hot today. The burping little trick didn't work. 

Torbeach, I have checked my vent tubes and they are ok. 

Just for info the bike is completely stock and has 41k miles. It first stated happening around 22k miles.  After the valve adjustment it did go away for a little bit( about a month).