Hey guys I have a 300ex and I was wondering where are the oil seals located? My bike smokes and I redoing the top end I just want to know where the oil seals are

 

Oil burning on a 4 stroke would be from oil getting past the piston and rings into the combustion chamber or through worn valve guides leaking past the valves into the combustion chamber. Crank case seals wouldn't have anything to do with smoking if this is your question.

 

Well I am big boring it will thats solve the problem? I am getting a new piston housing with the bore kit. And where are the valves?

 

You need one of these and read over it before you do any thing.http://www.ebay.com/itm/CLYMER-SERVICE-REPAIR-MANUAL-M456-4-HONDA-TRX300EX-SPORTTRAX-300-2001-2002-2003-/271803080287?hash=item3f48b9de5f&vxp=mtr