Hard Starting 2016 GRiSO

I've had this problem show up twice in the last five or six times I started the bike.  Hit the starter and the bike doesn't fire right away, just keeps turning over.  Add throttle and it starts but need to keep throttle partly open for about 5-10 seconds with light revving, then the idle settles down and idles properly.  No rpm variations like the stepper motor problem.  This has happened once when the engine was cold and once when the engine was warm after a stop for a bathroom break.  Is this the spark plug cap arcing problem or is there something else that needs to be addressed?  Prior to this, the engine always started normally when I pressed the button (except for when I had the "startus interruptus" problem which I solved with the wiring fix described here in the Ghetto).

Thanks,
Alden

Maybe a sticking air solenoid/stepper motor - pour in some carb cleaner down the air tube to the stepper motor - can't hurt and may fix it.

Has your bike still got the charcoal canister and tank venting system installed? It's summer for you now, was the ambient temperature warm or was the bike left in the sun before this happened? It sounds to me very like the problem caused by excessive fuel vapour from the canister causing the mix to be artificially enriched. The fact that giving it more air for a few seconds clears the problem would seem to back this up.

Pete

Tony -  I need to get some carb cleaner and add that to my shop.

Pete - yes, the charcoal canister is still installed on the bike.  I have not done the canisterectomy yet.  

The first time it happened, the bike was in the garage and out of the sun.  Temp in the garage was probably 65-70 degrees F.  Today when it happened, temps were in the high 70s/ low 80s and the bike was in full CO sun at 10,000' elevation.  The bike probably sat in the sun for 30-40 minutes while I had a pit stop and we talked to some folks who asked about our bikes.

I'd suggest perform the canisterectomy as a first step. This is a problem that only seems to affect some bikes but at least disconnecting it and removing it will rule it out as a cause of the problem.

Thanks, Pete.  I will give that a try to see if that corrects the problem.

Update - Canisterectomy is complete.  Now I need to go get a ride in to check it out.  

Thank you again for the quick technical assist!

Alden