Yeah I had the same experience with my brand new 125 deluxe,
I would suggest u to ignore the rattling noise as this is trademark of deluxe and about top speed,
Let it cross 1000km mark ,
U will see a significant increase in top speed touching 90kph Easley.
I just came back topping up some fuel in my ybr,
And did 105kph and bloody road ended.
Loving this yamaha man seriously.
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