OIL leaking from my breather hose on top of the crankcase on my ttr 125

SOURCE: crack in my yz 125 2001 crank case

You know aluminum can be welded very successfully now, so best bet is to remove that case and take it in to a good welder..You can ry the quick fix (JB Weld) is what i recommend, but success is rare !....good luck to you my friend...Tim

SOURCE: Oil capacity for a 2004 Yamaha TTR 125 LE

1.2 litres or 1200 mls buddy

SOURCE: iv just bought a tzr 125 belgarda its smokes like

There are two places where gearbox oil can leak into the combustion process: from the gasket between the two engine case halves, or from the crank seal on the right hand end of the crankshaft. The most likely culprit is the crankshaft seal.

SOURCE: G'day my 08 wr 450f is blowing oil through the

Im havin the same prod with my bike 08 wr450f
Looks like im gonna have to put it in the shop.

SOURCE: oil leaking out of power valve hose

Oil leaking from your powervalve hose could be caused by a few things mate. First thing to check is your air filter.A blocked(due to dirt)air filter is the most common cause of a rich running 2 stroke. If you have cleaned it recently, be sure you haven't over oiled it. if your not sure, after applying the oil wrap it in a clean cloth & squeeze it (don't wring it like you would clothing) this will remove any excess oil. I recomend a proper air filter oil(from a motorcycle shop) but don't recomend the "no toil brand" of airfilter oil unless you clean it out after every race( if you race your bike),grease the seal & replace the filter in the bike.If you don't have propper air filter oil you need to use a thick oil otherwise the oil will sink to the bottom of the filter.
Next suggestion is your oil fuel ratio. If you are using one of the ultra expensive synthetic or semi-synthetic oils try leaning its ratio to 40:1. Be sure to very regularly check your sparkplug colour after doing so. It should be a tan colour & not wet,black & oily.Please be very vigelant with you plug checking as if you go too lean a seizure can occur so only try this if the other checks prove ok.
Another cause could be that the powervalve seal(behind the cover) has popped out letting the oil/fuel out. Replace/reposition the seal & this should help.
Another suggestion is to check your gearbox oil. Is it dissapearing yet you can't find a leak? This symptom indicates you have a blown crank seal. If so it is allowing gearbox oil to enter the crankcase & is richening your oil fuel ratio due to this fault.
Finally it could be running just too rich ie delivering too much fuel/oil mixture. This is commonly expressed by the symptom of a very wet & oily muffler.To rectify this you need to reduce the size of the main jet in the carburettor. After diong so you must carry out regular plug checks like you did for adjusting the oil/fuel ratio.Care again must be taken as to not seize the engine.
Hope this helps regards
Andrew Porrelli
PS look for my tips on 2 stroke mx'ers comming in the next few weeks