If your fuel is old and it fails quickly, It s a bitc*, remove seat, shrouds, 6mm bolt on gas petcock,disconnect fuel line to card from teh petcock. remove tank hold down its tight. tank shoudl come off with petcock, fullign drain tank upside down it quickest, pour into your truck it will mix with good gas, and loosen the bottom 17mm (use a box wrench for best contact on all six sides-light pressure to snug) carb bowl drain, it will need a few turn to clear o ring, hopefully you have no sediment, I am surprised at teh debris in our gas, it settles quickly in your bowl an ddries as a amber/white product. Yes you can kep teh battery hooked up to bike 24hr a day if yoru "Battery Tender is of the proper type it should read it is able to regulate voltage and amp current into battery. Once a battery is sulfacted, left DEAD for a tiem it will never hold a charge. The batteries on CRF250x 450x are of a sealed nature. all position same as on the CMX 250 street bike REbel series. VERY pricey, as long as you keep it in full state of charge life is good. The VP fuels are not good in a bike that does not see race day only, save teh money, use best pump gas available. I cant see why Honda made a port for a screw and drain even hook a hose to it. I thought I saw a CALIF model that had a drain screw, the CRF450R CA model had it 2004 . Go figure. GOod Luck See you in the saddle /s/ Bill