I just started my bros 400 fr the 1st time in months.I got it finally going an was letting it run on idle occasionally giving it gas while I lubed chain,greased it etc all of a sudden as I was finishing up greasing it I heard the rpm in the engine change pitch,as I rode it into the shed .The vibes thru the handle bars were insane.I shut it off immediatley an noticed the coolant was over the line in the overfill.I hope I didnt take ay bearings out or overheated anything.It has a flat tire but I doubt this would cause the problem.The machine I got last May for Memorial day,It cant have more then 5-10 rides on it.If any 1 has advice for me an not that polaris is crap or garbage I will be more then enlightened to listen.And if ya dont have anything nice to say I would appreciated if ya kept it to yourself an not posted.Thank you!