I also have the (now well known) hot start issue. Glowing header at idle. Backfire at engine braking. Weak power at just-off-idle revs (as when just slipping clutch to set off in a gentle mannor...).
If you for example stall it, it just won't e-start when engine is warm), air is cold (have only ridden my bike at low temps, from minus 5 to +10 C) unless you:
- pull cold-start knob
- OR crank it 2-3secs on e-start with full throttle, release e-start, close throttle, push e-start.
Tried to get my local authorized YAMAHA-dealer to get the problem. First they said they didn't have the FI-tool, then that they did, but the tool could only set the O2 temporarily, and that it would go back to stock (0) setting after restart of bike!!! I mailed them the essentials from this thread (part-no of the FI-tool, how to plug it in and what buttons to push, in what order), they replied that they couldn't help me... Sooo dissapointed.
Found out that Yamaha Scandinavia (I live in ) don't have a contact E-mail.
I'm gonna call them on monday. If I don't get the right answers there, I'm gonna raise it to Yamaha Europe...
Bike is a 2012 with euro-spec ECU (1DX002M29E00EB), Yamaha competition kit header (slightly lager diameter than stock, without O2-meter) and Yamaha competition kit alu Slip-On. Snorkel in place.