@silent.teers2003
It was your mistake why did you pay full amount before Legal biometric transfer.
You should stop 50% payment at that time by making payorder that he could verify the genuine-Ness and handover to him at the time of biometric transfer.
There is no value of that card and papers which you have as legally bike is on his name and he can claim anytime that he had lost those etc. Allah na karey Lekin Jo 5 months se transfer taal raha hay, us kee harkat par kiya comment kiya jaye?
Main point is driving or owning 5 months on open letter was not the wise decision and even no one can write any term in agreement which is against the law like he will be liable to transfer biometric even after 6 months, such clauses which are against the law has no legal value.
Anyways, try to solve it calmly with him first and even if he is not agree after this then hire a lawyer and send him legal notice and proceed case through courts