I'd suggest that it probably has more to do with battery strength/health than anything else. This is my first winter with my 800GS and it does the same in the cold (sub 35 degrees). It is especially noticeable if the heated grips are on during start-up or the aux lights are on (dumb yeah I know). I don't know yet whether the stock battery is underpowered or whether mine is going bad. Heavy and even standard weight oil will exacerbate the problem if the bike is cold... These bikes have a boatload of electronics that power on at the same time that the starter is struggling to bring the beast back to life so it doesn't surprise me that the amperage drops almost instantaneously for a few moments - enough to reset the computer.
I noticed similar behavior on my 1150 GS right before I replaced the battery... instant fix thereafter even when temps were in the teens or near 0. I'll probably be replacing my battery shortly (its an 09 and OE as far as I know). Car Batteries have 2 ratings and the CCA cold cranking amps is the one you care about the most in this weather - I'd assume that motorcycles do the same.
On the li-ion battery - I've seen on many camera forums conversations about how performance of li-ion battery packs degrades more than nicad in cold weather ( sub freezing temps), so it wouldn't surprise me if that same effect was manifested in a big bike battery.
Originally Posted by h2only
been cold here and started the F800gs up today, turn the key, all the instrument gauges move and light up as normal. Hit the start button, one click of the starter, nothing, hit it again, fired right up. Then right after it was running, the gauges light up again and the tach and speedo go all the way through their sweep, then all is normal.
Did this a few times with the same results. Thinking maybe battery, I turned it off and plugged in the battery tender, the charger showed full charge after about 10 seconds.
Any ideas what would cause this?