Central Park Cyclist

I was already in the park with all the bicyclists zooming past when I thought I might have a go at panning.  I quickly googled this on my phone, hoping for some hints on optimal shutter speeds and technique.  As I took about 400 shots, I learned a few other things: Getting them on the straightaway after the downhill is better than the uphill and this is really hard to do.  I can see I will need a lot more practice. Central Park on a sunny Sunday morning is the perfect location because there are hundreds of cyclists. 

I liked this shot best because most of him isin focus, but I also liked his style.  I will post my only other decent shot and probably the better of the two,  in extras.  

If any of you have ever tried this and can offer me some advice or tips, I would greatly appreciate it.