1986 Yamaha XJ600 ENGINE NOISE and Oil SMOKE

A buddy bought the bike, rode it, Sold it to a friend, and then got the bike Back, it Had no oil he said so he put some in, rode it half way home, It started to smoke and knock from engine, HE then GAVE the bike to me for coming to get him and the bike. "IF" I wanna fix it? short from buying a motor if that is what is needed? Whats This noise sound like to you, im not mech inclinded where bikes are concerned But can work around a car, Engines are the same concept But.... Im suspecting a Possible Connecting rod let loose or something? Where would i start. Has a mild knock to it, Idle's, runs, smokes, and Not alot of power when i tried to run it around the block... cant see a crack in the block but oil is getting in exhaust and smoking HELP?
i uploaded a video of it on you tube located here-----> http://www.youtube.com/watch?v=xiz89uk3tos
Any help or input is greatly Appreciated. THX

 

Do a compression test; and quit trying to run it until you diagnose it.

 

I dont have a compression tester, I only started it for the video, Figured the Video SOUND, can help Diagnose the Problem, In a car when a Connecting rod goes it wont run, Idle, Ect, The bike idles and runs Just smokes, and Makes a slight knock from the bottom? I am Assuming, But I dont wanna do that... Assuming that is... LOL Oh yes Has some oil on the engine but unsure where it came from, i just got the bike last night, Thx

 

Check your plug color... That's a start, sounds like it's only firing on 3 and by the looks of the smoke it's from either hole 3 or 4.

You should be able to get a compression tester for pretty cheap, they're not hard to come by and will let you know how strong or tired those cylinders are. On the same token that xj600 sounds pretty tired and if it was run without oil or went through what it had you're likely looking for a second hand engine. When shopping for that you'll need a compression tester then as well so you don't buy something you regret.

 

is it possible to over fill the oil and it burn/smoke like that? The kid i got it from dont no squat about bikes and may have over filled it, When i get home im going to check that and see if it has to much in it.... i had it running again later that day at an idle "NO SMOKE" Gave it some gas? NO SMOKE, untill i revd it up a bit but Not as much as the first time i started it? rings Maybe going bad, im just trying to rule out all possibility's before i go tear down the engine or go buy another one. The plugs Proubly do NEED REPLACED for sure. Dont think he ever did that when he got it, I sprayed off the Engine with some gunk cleaner and water, there is no Extra oil on the block like before SO?

 

If you google for a manual you will probably find a free one to download. Make sure you have the right quantity and type of oil. You really need to check it over as has been previously stated. A compression test will tell you if you are looking at $10s or $100s.

If the engine was grossly overfilled, it could push oil into the air filter box.

How many miles has it done? For the record, it is a "Seca II" XJ600 from 94 - 96, not an 86 XJ600. Just so you get the right manual!!

Of course, I would be happy if you put it in a crate and shipped it to England.....

 

Or blow it up for real. You pick.

If you're serious about trying to "salvage" the bike, then pay attention.

TEST THE COMPRESSION. QUIT TRYING TO RUN IT. If it HAS broken a serious component, then all you're doing by continuing to run the motor is making things worse.

You wanna fix it or not? Then get serious and do it right.

I'm out until I see some compression numbers. Good luck.