I've had an unfortunate situation happen with my exhaust. I went out to start my scoot on a VERY cold day only to have BOTH exhaust bolts fall off into the grass to be lost for good, I just need to know the size and thread so I can buy new ones down at the store. Needless to say it's not good to run without an exhaust for obvious reasons (aside from the noise, which actually is pretty cool) like burning out a valve or "piston slap". The only reason I started the bike was to keep a charge on the battery during some extremely cold weather this week. I'm thinking I'll fetch a battery tender next time