The metal sound you're experiencing is normal, nothing to worry about, probably your valves might require adjusting, which can be done during your service schedule by mentioning the issue. Secondly, bike pulling to one side can be caused by lower tire pressure and either a loose or tight coneset, take it your local mechanic or your Yamaha service center and get it adjusted accordingly, it's hardly a three to four min job.
A vehicle should take a straight line when hands are off the bars.
Cheers!
VJ




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