Razor Chopper C300 low end grunt

I have a razor chopper that I ride double with my three year old, me 200lbs - son 30lbs. We have a ball cruising around the block but need a little extra power on the hills and take off. I ordered a +5 kit (mykwilwin.com - Buy Now) that lets you intall an RC battery to the bike and was also thinking about a smaller sprocket to help during the take off. The front is now 11 tooth, I tried to find smaller one at TNC but no luck. Any help whould be great.

Try to find a larger rear sprocket, probably will need a longer chain too. Hopefully it mounts with a standard thread pitch. If you volt up enough at the same time, you may not even lose any top speed with the larger sprocket.

Be careful with your kid and the lipo pack. I would mount it away from where ever he sits. They are pretty safe, but on the off rare chance something goes wrong it could be bad to have him near it.