I won't translate the whole thing, but suffice to say he was impressed & liked it a lot.
No, the French haven't found a way to make it street legal & will be the LAST place to do so, it's a total pita to register anything non standard here.
If you wanted one street legal, best place to register would be Isle of Man, I even saw a street legal racing sidecar outfit there!
Hell, on the IOM when you get close to race week people run full on race bikes through traffic and take them out on the mountain to see what they will do.
During race weeks it is actually completely legal to operate a full on race bike -no lights, no plates, no registration- on ANT public road as long as you are go to or from your garage to the race course. Cops will stop traffic to let race bike through.
My first time there I was sitting out enjoying an Okell's on the main drag on Douglas harbour watching the rush hour (such as it is in Man) go buy when we hear a two stroke engine ripping away and a few minutes later here comes a sidecar rig running down the wrong side of the road fully expecting that oncoming traffic will move over; and they did. I look at my buddy and we both just smile. There is no other place like the Isle of Man
If I can figure out how to pay for it I want to retire there. A very neat place, unlike anywhere else I have been. The bike racing is just the icing on the cake.
It would be fairly simple to make an XBRR road legal in the UK. A daytime MOT test is all that's required, which can be had from any 'friendly' tester. Road tyres, a brake light and number plate light, rear reflector, and a little packing of the exhaust prior to the test should see you ok. Then you apply to the DVLA for a letter 'Q' registration document, stating the XBRR is built up of parts and the year of manufacture is unknown. Alternatively you get hold of an already existing 'Q' plate registration document and adopt it to the XBRR. Get yourself some insurance cover, nip down the local Post Office and buy the road tax, and hey presto, you're fully legal!
How does the United States government feature on British road legal imported motorcycles? Or you could always emigrate.