A LIFe battery will spin it faster. Stock battery is 12.8Volts, LiFe is about 14.4. CCA (Cold Cranking Amps) only is the 'volume' of electricity available. Like a 2 gallon or five gallon tank of fuel. A larger tank will not make the bike faster.
The bike needs to have it (idle mix) set for ambient temps. The enricher adjusted to provide enough (and the right amount) for cold starts. A cold start when it is 60 degrees is a lot different than a cold start at 0 degrees. Two settings, two 'circuits' in the FI.
I have to disagree. CCA is the thing that matters how battery turns starter motor. Ah is the volume of battery and CCA is how much "juice" it gives out. Higher Voltage+CCA together help to make LiFepo battery great.
I ride through winter and LiFepo battery is not good when it really gets cold, like sub zero fahrenheit (-20 celsius). Above 30F it works great. A friend of mine has WR and Lifepo battery is all that is needed to get it start great cold or hot during summertime.
I have KTM 500 exc (but thinking of WR and that is why reading this) and all I have done to it is a bit higher idle and YTZ7S Yasa battery -> 0F is no problem on races that reguire cold start from parkferme on second day of race.
But the bottom line is that CCA is the thing to look when trying to get battery that will start WR best.
(I am not English speaking person so I hope this was understandanle enough)
Edited by roiala, January 24, 2015 - 10:29 PM.