Re: 200w petrol motor
I think only the 200watt kit (not the DIY kit) comes with a dyno certificate. I think most police will be fine with it, once they hear you rev it up, and they see it only revs very low.
Also keep all receipts and stuff with you so they see you bought them, and show the modifications you made using the kit.
The only place I've found that sells them is Zbox, and they sell the kit for $89+shipping.
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