superpower

You can actually fit 2 of these in the 16.0 Racing if you want to run a ridiculously long time. You have to orient them a different way though.

Voltage: 36V - 3x12V Capacity: 9 Ah this is LiFePO4 capacity which is equivalent to a higher capacity in a SLA battery Max Continuous Discharge Current: 18A Maximum Peak Pulse Current: 36A (2 sec.) Dimensions: 5.875 x 3.625 x 7.50 in. Total Weight: 7.8 Lb Total Includes built-in PCM (protection circuit module) with internal cell balancing and management, protection from over current, under voltage (over discharge), over voltage and short circuiting, and integrated charging circuitry.

The footprint is the same size as the SLA batteries the bike comes with but they are a little shorter in height - 3/4" shorter, to be exact. These weigh 2.6 pounds a piece for a total of 7.8 pounds. They just plug right in to where your original batteries were and you can even reuse the cloth cover to keep them clean. They are in a sealed ABS plastic case that is shock and water resistant.

Here is a picture of the power supply.

I have made a LiFePO4 plug-and-play solution. I am in the USA and these power supplies are manufactured here in the USA and are a custom for this application. This is not some home-brew setup with HobbyKing power packs. This exceeds OEM specifications and has a two year warranty (pro-rated) on the power supply. This is the setup that I currently use in my son's 2015 Oset 16.0 Racing 36V. I am an engineer and do this as a hobby. I can put these together for about $335 USD and that is what I would sell it for as long as its going in your kid's trials bike and you are not trying to screw me by reselling it and making $250. Not sure where you are located, but if you are in Europe I would have to look into shipping. Blessings, MS