I took my bike in to get an oil change at my regular mechanic (been going there for about a year, nice guy, I THOUGHT). I pick up the bike that night. The next day I am heading somewhere and about 5 minutes down the road the bike makes a horrible noise and cuts out. I walk it to the nearest scooter shop and the guy tells me there is no oil in it. He doesn't touch the bike. I get the original mechanic to come to where the bike is. He helps me get it back to his shop. He then tries to tell me that no, there is oil in it and the other mechanic didn't know what he is talking about.
I have to go somewhere, so about 3 hours later I return to check on my bike. He says it is running fine and there is no problem. I have him open the oil fill cap and yep, NOW there is oil in there. I ask him if he's lying to me, he says no. I leave with my bike. Drive it for 1 minute, and there is still this horrible sound that was never there before. I go straight back. Now I am mad. I accuse him more, enthusitacially, of lying to me and he finally admits it!! He doesn't apologize, he just says he will fix it. I am very mad so I tell him I will talk to him in a few days. I take my bike and walk it home.
The bike is an old used bike that was cheap, BUT, about 10 months ago I paid a different scooter shop about 9,000NTD to rebuild the whole engine (bottom and top end) (I got a good deal through a friend, the actual cost was actually about 13-14K)
What should I do. If this guy lied to me already, how do I know he won't just fix my bike with the cheapest and/or 2nd hand parts he can find? Any advice?
TL;DR: mechanic forgets to put oil in bike after oil change. I drive it and it breaks. Mechanic lies about forgetting to add oil, finally confesses and agrees to fix bike. I don't trust him now. What should I do?