i've got the same experience. and the answer is, sorry, but, NO!!. i have already posted it somewhere on hubb. but, briefly, the customs officer will stamp your passport says, entrered with a vehicle. and you can not leave the country without this vehicle, UNLESS, you park your bike/car to the customs car park and have the permission (a stamp in your passport) to leave the country and come back within 6 month and get the bike back.
so, you cant simply park your bike to the airport car park and fly away. if they realise that you have not the official paper to leave the country without your bike, you will have big trouble!
how do i know? while i was living in the UK, i rode to Turkiye and have the same problem like yours..
hope this help.
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