My 2004 kx 250f is leaking oil from where the shift lever and gear box meet, how can this be fixed and why might it be leaking?

Hi, is this from around the shaft? if so a seal is fitted to this, it is easily replaced by removing the gearchange lever, und using a small sharp pick to push between the shaft and the seal, with not much effort you can pull the old one out,clean around the shaft and seal area and gently push the new 1 in useing even force all round, TIP IF YOU LAY THE BIKE DOWN ON ITS RIGHT SIDE YOU CAN REPLACE THE SEAL WITHOUT REMOVING THE OIL.

First the causes of leakages has three explanations. Ocasionally the engine oil has to be replaced either as burnt out or simply to acquire new functionality. A continuous use of burnt out engine oil is capable of leaking as dispense mechnansim. Second, the engine oil should not be filled to the brim of compartment. An over oiled compartment displays overflows after vigorous biking experience. Third, insufficient oil in compartment causes the engine to over heat melting the gasket glue seal to the engine block. In which instance leaks are observable. How to fix the condition.
First, acquire replaceable parts mentionable as engine oil, gasket glue and filters.
Second, deciding on contacting a mechanic as alternative means to repairs or decid on fixign at elswhere as an arrangement. Third, deciding to fix at home for example would require a pack of tools that are capable of loosening the engine block area. Usually, two of three spanners of an appropiate nut size would loosen the engine block. The reason for loosening the engine block is to visually ascertain that no damages were made due to burn oil or event vigorous riding. Once the engine block has been removed, the bike splokets are exposed, and may be greasy requiring cleaning. The apppropaite fliud is required to spray clean the internal devices either as removal of greases of burnt slurg or simply to observe any damages. There after the cleaning is achieved, the parts to the engine block is replaced. The tools become handy in removing and tigtnining. Also, the gasket glue and filters become usaful as replacement of any wornout disposables of the preveoius. Once every parts are tightened back in place, the new engine oil restores the bike to regular functionality.