my super power sp 70 euro2 2015 model Super Power SP 70 2015

My bought this bike 8 months ago.in style and comfort this bike is awesome but with speed I am not satisfied with it. On fourth gear it only reaches at 70 and start vibrating.other wise it is the best bike i ever had. if any one have solution of this problem please let me know.

• Style
  
• Comfort
  
• Performance
  
• Fuel Economy
  
• Value For Money