8 .
Your plans for the day would be a great deal easier to manage, and more flexible, if you could borrow a bicycle from an English friend instead of relying on public transport. If this is a good enough friend, they may be willing to let you borrow the machine (which is of some value to them) if they aren't using it anyway, and if they are happy about you being able to ride it safely on 'the other side of the road'. All these factors considered, how do you set about asking to borrow the bike?
If I had the use of your bike tomorrow, just think how much easier that would make it all for me.
You know, it'd be ever so much handier if I had my own wheels for the day tomorrow. D'you think I could just borrow your bike?
I wonder if you'd mind me asking a big favour of you. Might there be any chance of me borrowing your bike tomorrow please, just once and only for the day, if I promise to take good care of it?
It would be such a kindness if you could see your way to letting me have temporary use of that magnificent bike of yours, you know my heart would be eternally grateful.
Answer 2 starts well but then becomes rather dismissive (as though these friendly people would not make the effort to appreciate other commitments within your life).
Answer 3 is very rude and offhanded, and as such would be unlikely to encourage the people to bother with inviting you again; and Answer 4 does not 'leave the door open' from your side to another future suggestion.