Adding a 2nd battery for 24v starting...

Hi Sam. Here is a schematic of how the system is installed.  Basically there is a second battery that is installed in the left side pod and gets wired in series with the current battery.  There is also a charging box that keeps the second battery charged.  This is needed because the engine charging system is only capable of charging one battery.

I know someone that is selling a used kit if you are interested.  Or you can buy a new kit from Spring Mountain.

Charley

I have seen a lithium “booster battery” placed in the wire going to the starter on a Hayabusa powered Thunder Roadster. The down side is that battery needs to be charged separately each night or maybe more often. 

To put it very simply, take the positive wire that runs to the starter motor, take it off the starter and put on the negative of a second battery. From the positive of that second battery run it to the starter motor.

This will give 24V starting whilst leaving the rest of the car at 12V.

Radical have a split charging system but a decent battery would last a few trackdays before needing a charge so just remember to charge it at home when you can.

Awesome. Thanks everyone! 

must say, been on this site for a week now as I’m off to buy a SR3 tonight and the help has been fantastic! So thanks one and all! Shame I’m based in the uk and guys are prominently in the US.

@m22ble Post some pics of the car when you get it! I’m sure there a quite a few forum members on the other side of the pond. Parts are easier to come by where you’re at. I see quite a few radical spares posted on racecarsdirect.com which is in the UK.

If anyone is interested I heard from the guy that has a used set up to add 24v capability to an SR3.  These parts came out of a 2015 RSX but will work in all generations.  They tell me that the new parts cost $1295 and they are selling these for $750.  This includes the charger and all of the wiring... I asked them to double check to make sure the bracket that holds the battery is included.  This is a good option if someone wants to have the on-board charging.  But it also might be worth trying what Dan suggested and charge the battery between track days??

Charley

Here is picture of the charger, but the other parts are included also.

HI all,

I am currently using the Odyssey batteries with the 24V system but I was looking at some lithium batteries as a direct replacement. The only issue I can think of is the charger supplied by Radical as it is not designed for a lithium battery. Is anyone using such a setup? 

Hi Horta (@horiap), I haven’t tried using a Lithium battery yet, but I would think it would well.  It is my understanding that Lithium batteries can be charged at the same rate as AGM batteries.  They can also be charged at a faster rate, but using the standard charging should be fine.  I would check with the battery manufacturer to be sure.

Charley