is there a motorcycle dealer / leasing accept credit payments motor using bitcoin?
I am guessing, wherever and whichever country you are, there is none that will give that loan to you. It would be better if you just got a loan with the bank and paid the motorcycle with fiat. Then when it is time to pay your installment just convert your bitcoins fiat and pay the bank. Easier than finding someone accepting bitcoin payments.
Your right I don't know if there's country who accept bitcoin as payment for loan regarding motorcycle. There's were some goods or items whose buy in the market or online shop were paid by bitcoin currency, however in terms of vehicles I can't encountered people who accept bitcoin as exchange of it.
It is not mainstream for the vehicle shops to accept bitcoin as a mode of payment because the companies are not yet interested in bitcoin and they don't prefer a currency that doesn't have fixed amount of value so it is hard for them to trust bitcoin and accept it. Bitcoin is not yet world wide known as a great currency so it might be a factor why vehicles sellers are not accepting bitcoin.