I have a 1989 fzx 750 and there is oil leaking through the alternator,,any ideas,,also is there a breather hose on the engine thats supposed to be releasing little bits of smoke ??

It may have a crankcase breather hose/port around the back end of the engine which allow the lower engine to breath. If the engine has been over filled with oil/the breather hose lose/broke, or has excessive blowby (bad rings), the engine will push oil out. Most 4 stroke motorcycles are not designed to stay with the front end in the air for long periods of time or the engine will run short of lubrication and eventually fail. If you want to keep the front wheel up the engine will have to be modified so that it can lubricate while the front wheel is up otherwise it will cause damage!

That can mean there is high blow-by internally in the engine. It can also mean an internal leak from a crack in the block, cylinder wall, piston, piston ring, ect.
How does it run? I have seen some older bikes "blow" a little but keep a close eye on oil level and check spark plugs for heavy fowling.

Most likely cause is carb flooding due to sticking/leaking float valves...

You most likely have an air leak in the intake tract. Check and make sure your vacuum hose or hoses are attached also check for air leaking into the intake behind the carbs. When the bike is running, spray carb cleaner between the rubber boot and the engine. If engine changes rpm you found your leak.

Hello check your engine oil level to see if it is over filled.
Also if it is smell it to see if there is gas in the oil.
what some times happens with older motorcycles the fuel petcock o-ring or diaphram goes bad and fuel will weap into the cylinders and into the crankcase. raising the level and pushing into the air box via the crankcase breather hose.
Also check the vacuum line from the petcock if it has gas in it the diaphragm is leaking.

Better, get a new one. If you must remove slave cylinder, take out internal circlip, remove seals, wash in carbontetrachloride or similar, air dry, refit new seal kit lubricated with dot 40 and slide home, refit circlip fill and bleed air, topup, simple yea

My 96 Discovery has a plastic baffles inside the valve cover port that connects to the hose. If it got brittle and cracked, then oil could leak by. Its cheap and easy to replace, along with the hose. There is a second hose on the other side to replace as well. Land Rover was proud to pass emissions standards without using exhaust gas recirculation (EGR). The whole system is sealed, so all the air entering the engine is being metered by the Mass Air Flow (MAF) sensor, unless your breather hoses crack and leak. Unfortunately, oil in your location might also indicate other engine trouble, such as worn piston rings (causing pressure in the crankcase). I would try replacing the plastic baffle piece first.

Sometimes a chain will come off a sprocket and get wrapped up at the casing. The casing usually will get cracked or actually broken. A replacement casing from the parts department comes without a full serial number. The 1FM designates the case to be a replacement casing. Legally, the dealer was supposed to punch in the original numbers from the owners title. The bike is special in that it is now 20 years old and is now considered an antique in most states.

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