yes you can and you dont need insurance to ride it on a road
yes if you weld a bit of meatal and do wot ever you need else to attach the engine to it.if you want to get en engine on a bike i would instead of spending 150 quid on a bicycle engine i would buy a mini moto engine for 35 quid plus it probably go faster.a mean my mini moto does about 30to35mph
depends how small, if its medium sized, i believe its 16+ of age if its a small one, anybody can use it ================================================== If you are using it in the UK you do not need a driving licence to ride ON private land If you are using it on a public road you will need a driving licence and insurance and the mini-moto will need to be taxed and MOTed.
In Liverpool
no
Well when you race in like crmc you do need insurance and just riding the road and the pit and things like that you might want insurance just in case you do fall and you break a leg and if you get your bike stolen. Try looking at Bike Sure for the insurance. They specialize in niche bike insurance such as this - http://www.bikesure.co.uk
Need spark plugs
yes
yes
it is just like hooking up a 6hp engine in a mini bike all you need is a bigger space to put the engine in.
no no no no
yes, you can ride a mini motor at twelve as long as its either on a local track field or your own property, you need a helmet on at all times though.