Cool video. Any issues with the Oset so far?
I'm going to look at the new GasGas Enduro 2 pro when they are in stock near me. Oset is another option. My 5 year old just moved up to a de-tuned kx65 that's been lowered. Looking for a good fast electric bike before the neighbors have a chance to bitch about the noise. He's tall for 5, and I think the seat height on the Oset is pretty low.
If he's on the bigger side I would check out the Kubergs. My son started on an Oset 12.5 then moved to a Kuberg Cross (Oset didn't have the MX10 then). Seat height is 25", bars are 32.5". 3kW motor. It has 16" wheels and LHRB. You can set power/torque and top speed separately.
They have the basic Cross (what my son has, only model they offered back then) and the Cross Hero (which adds better suspension and a waterproof controller). If he's planning to race in a wheel-size restricted class, they also have a racing version that has an 8kW motor, 10/12 wheels, and a rear foot brake.
The Cross has been rock solid. Replaced the batteries after 2 years. Standard lead acid used on electric wheelchairs. Super common. Only problem we've had was when he crashed it so hard the battery connector came unplugged. Plugged it back in and all was well.
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