what is this GY200?

[rjmorel]

So I rode it around today and put another 30 miles on it. Everything seems fine except when coming to a stop I get a gravelly chain grinding noise that is bugging me. I took off the counter shaft sprocket cover and then the plastic chain guide thinking chain was rubbing on them. Then tightened the chain a little .
Still does it.
Pushing around the parking lot and using the front brake off and on I can get the front brake to chatter like a cow having a calf. The outside part of caliper is bolted to the forks solidly , but the inner part that holds the pucks has play in it , more then my other bikes. So I'm wondering if this is normal to do this or if you guys have experienced it and came up with a fix? Thanks, Rob