Again, my concern with the stock Savage charging system was the potential to overcharge. 15.5 volts is listed as the acceptable top rate of charge for the stock R/R. This will kill any lithium battery I've ever seen.
So, if you test the bike, and the R/R you have is allowing the system voltage to go this high, swap out the R/R. If you are going to do that, why not use one that is designed for a Lithium battery?

From the Antigravity site:
The Antigravity Battery normal voltage is 13.2V. The battery will read up to 14.7V immediately after charging. The normal operating range will read between 13.3-14.5V. After a few hours it will self-balance to the 13.3-7 range which is its normal state of charge. The maximum voltage the battery should be exposed to is 14.7V. On the lower end of the voltage range the battery should be put on a charger if the battery voltage drops below the 12.5V range while sitting. The voltage should not be allowed to drop below 11V while at rest. Permanent damage may occur below 11 volts.

If the battery shuts off the over voltage and the R/R constantly produces too high a voltage, you will in short order burn the R/R.
The R/R has to dissipate it as heat, and unless its dumping less than 20-30% of the output from the alternator as heat it will die in short order.
Then you don't have to worry and buy a mosfet R/R LOL.
Cool.
Srinath.

So, when the stock system ramps up to 15.5v, the battery shuts down incoming electrons? Hence, the battery isn't being charged? Maybe a nice feature to protect against momentary voltage spikes, but not so great when the battery won't be charged for long periods of highway cruising.
Unless I'm not understanding.