Intermittent backfiring TE310 then wont start!

This is starting to drive me nuts. Any help appreciated.
Bike is 2011 model - all power up done. 1400 miles. Run on 97 Octane. Regular oil changes (fully synthetic), oil filter changes and air filter clean.
What happens: Bike starts and runs fine for few hours. Then starts viciously backfiring then engine starts dying and finally comes to halt. Difficult to get it to start again. It fires but doesnt hold an idle and stalls. You have to try and coax the idle on the throttle but it wont necessarily hold the rpm. It takes multiple goes to get it to start. After a period of time it starts again and then runs rough for rest of day. Then next time out it seems to start and run fine initially before whole thing starts again.
Last saturday it happened again, but this time it would not start at all and eventually battery flat on e-start. i had to wait 4 hours by side of road for recovery. Bike recovered to dealer. He jumpstarted battery - bike burst into life - runs fine no problems . No fault codes show up. Dealer replaced the temperature sensor before. Whilst out and couldnt get it to start tried pulling out the temperature sensor - no difference - fan comes on but bike wouldnt start. Pushed in throttle body and tightened up bolt really tight on the banjo clip - still wont start. Dealer is perplexed as it worked when it got to him and there are no fault codes: He's taken it out and confirms it pulls hard when throttled.
I'm really not very mechanically minded so i'm guessing it can only be one of the following in decreasing order of likelihood: (incidentally anyone know whether these always show up as fault codes?)
Fuel pump intermittently working
Battery faulty
Dirt in fuel pump / fuel filter blocked
Some sort of throttle sensor (i imagine they probably have one) not working

Any help / ideas / confirmation of a known problem hugely appreciated. I'm just about to disappoint my friends and pay for / miss a trail riding holiday starting end of this week if i dont get it sorted!

I love this bike but it looks like we are heading for a nasty divorce!

Thanks in advance

I know you changed the temperature sensor already but it almost sounds like that's what is wrong again . I had a similar problem and after going through the fuel pump seating issue the temperature sensor, the throttle body which looked as if it was seated but it wasn't, and replacing the fuel pump relay and main electrical relays the problem diappeared. You may want to check your spark plug cap to the high tension lead from the coil, I've read that has been a problem with some of these bikes . Also look at the intake manifold boot to the engine to make sure that bit is not cracked anywhere . The throttle position sensor is also another area to check if it is off it could cause problems. The other thing that I did was to check all the ground connections and also take a good look at your fuses they may look good but may have a hairline crack that is intermitently opening when the bike gets hot . I hope you get it sorted out for your trip.

In addition to what waserman said- I am curious if you use a one way valve on your fuel cap- if so it can build pressure or create vaccume- use a strait hose (free flowing)- OR/and when it dies andwon't fire- take the cap off- reprime and see if it starts easier. If so- take the one way valve off.

No i use the normal fuel cap and hose supplied with the bike (straight - free flowing). I checked but no vacuum seal when i undid it.
I even tried starting it with the temperature sensor taken off just to see if it would run without that on - it should run rough but at least run (but no joy). Throttle body on as tight as possible and dealer pretty convinced the throttle body was properly seated.
Thanks for suggestions - i'm going to pass those onto the dealer and see what he can do.
I'm starting to think it might be a relay or battery issue. When it last died whilst riding (on saturday). I tried leaving it for a while (couple of hours) to cool down. Then tried starting - again fires - doesnt run. After multiple goes on e-starter battery flat. When it got to dealer few days later with flat battery he jumpstarted battery and it fired up first thing. Makes me wonder whether the problem is the battery is getting enough charge when its drawing a heavier current eg running in race map 2 at low revs in higher gear. Also whether the result is its got enough power to prime pump (i can hear it cycle), and enough to spark but not enough to keep pumping fuel.

Aaaaargh

Well this is just another thought , perhaps the flywheel has come loose and sheared the key . It's not unheard of and the back firing is sign of timing being off . I think there have been other X-lite motors with that issue .

My money is on fuel pump/fuel filter. When my fuel filter got dirty at about 6500 miles, there was backfiring, dying, starting again, dying again, etc. I immediatley pulled my fuel pump assembly, which is kinda home-made, and I checked the fuel filter and was plugged up pretty solid. Got a new one and all is running smoothly again

I'm really appreciating all the help from you chaps - thankyou .
Am i right that the "pickup unit inside the mag cover " is the fuel pump assembly?
I'm passing all this onto the dealer for him to investigate. So far a few things have been looked into and discounted eg throttle position sensor is in right place. Glad its under warranty because the bill would otherwise be horrific. He's going to pull the pump to check seating correctly / fuel pick up in right place (shouldnt be a problem as it stalled on flat couple of times) and i could see the pump immersed in fuel. I'll remind him to check the fuel filter (which i assume he will do anyway). The next thing to look at is whether all the wirings ok ie relays and there's no arcing, good earth etc. The bit i dont get is why its now running fine and does so when ridden for three or four hours before it decides its not going to work again. Then once its had a rest (first time a 20 minute nap, next time a whole weekend off), charge battery after i flattened it trying to start it, it bursts into life and gets going again, pulls hard - rides fine.

Thanks for everyones help.

That's right...they actually melt.

I have 2 melted ones on my bench right now.

(Poster formerly known as Husky pimp!)
Nothing seems to be resolving the issue - sigh - all of above checked and no cigar, fuses replaced, loom checked, fuel filter changed, its a complete mystery. Sometimes it runs fine all day sometimes it stops within five minutes of riding. Last case in point today when it wont start at all. But the bizarre thing is that it bursts into life the next day.

I'm heading for judicial separation at this rate.... If anyone has had this problem and suggest an answer i would be grateful - this is the fourth time it will be going back to the dealer...