How can I stop a guy from racing his Harley up and down the street all weekend?

It's so loud. It wakes up the baby. We can't have a normal conversation in our backyard.

Throw tacks on the road. Or you can go the rational route, and try to talk to the guy and tell him your problem, if this doesn't work file a complaint with the police.

PrAy............PrAyErS will help?ByE.?

That's easy. A single call to the cops complaining about this guy usually has a fairly swift effect. If it doesn't work quickly enough call back regularly.

have you tried having a conversation with him?

Either he will be a punk and you will have to resort to the cops,
or he will be cool and you will have a new friend.