Oil in Magneto

So my magneto case seal has been leaking a little bit for a while now, i just upgraded my spark plug to a ngk from a chinese plug, and added an expansion chamber. The bike is much faster accelration now, better hill climbing, and 10kmph more top speed. (would have got a magneto seal for 2 bucks but they were all out at the time and i figured a tiny leak wouldnt hurt)

I was riding though and ntoiced when I hit around 40-45kmph speed the engine really starts to open up and it starts going to about 50 maybe even 55 kmph.. then with WOT it just slows down on its own to about 40 ish. After a few seconds it starts going faster again speeding up to 50.. It will repeat this.

During my ride all of a sudden I am hearing a weird sound and the bike is not running right, only about 60% as fast as before. It bogs tremendously and won't go high RPM with or without the clutch engaged. I got home and checked my crank clutch side case - It is fine. I check my magneto case - 2 big spoon fulls of oil, at the least. All over the place. Has my magneto seal finaly blew a nice hole? Would that magneto side crank case leak be whats making the bike run crappy all of a sudden?

I was a bit worried that something inside the cylinder of the engine went ( bearing or something ) but would the bike even run at half if something in the engine itself went? Does this make sense?

-UPDATE- Okay so I did some more searching and It isnt the easiest to start either - I live on a hill so I just go down the ally way but it doesnt get/stay started for about 30 seconds. And i read that this case seal leak is as bad as an intake leak. So that means it would run poorly. Bingo?
 
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So my magneto case seal has been leaking a little bit for a while now, i just upgraded my spark plug to a ngk from a chinese plug, and added an expansion chamber. The bike is much faster accelration now, better hill climbing, and 10kmph more top speed. (would have got a magneto seal for 2 bucks but they were all out at the time and i figured a tiny leak wouldnt hurt)

I was riding though and ntoiced when I hit around 40-45kmph speed the engine really starts to open up and it starts going to about 50 maybe even 55 kmph.. then with WOT it just slows down on its own to about 40 ish. After a few seconds it starts going faster again speeding up to 50.. It will repeat this.

During my ride all of a sudden I am hearing a weird sound and the bike is not running right, only about 60% as fast as before. It bogs tremendously and won't go high RPM with or without the clutch engaged. I got home and checked my crank clutch side case - It is fine. I check my magneto case - 2 big spoon fulls of oil, at the least. All over the place. Has my magneto seal finaly blew a nice hole? Would that magneto side crank case leak be whats making the bike run crappy all of a sudden?

I was a bit worried that something inside the cylinder of the engine went ( bearing or something ) but would the bike even run at half if something in the engine itself went? Does this make sense?

-UPDATE- Okay so I did some more searching and It isnt the easiest to start either - I live on a hill so I just go down the ally way but it doesnt get/stay started for about 30 seconds. And i read that this case seal leak is as bad as an intake leak. So that means it would run poorly. Bingo?

Yes bingo!

With the seal leaking this hard, there isn't pressure to transfer the air to the combustion chamber.

Felipe Cobu
 
you may just need a new seal. but be sure to pry up on the end of the crank there and see if the main bearing has gotten loose (crank should not move at all up/down)
 
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