Exhaust fumes coming from the air box? KZ440

Hi all!

I'm a new member on the forum. I've just bought my first ever bike, a 1984 KZ440Belt.

I was out riding yesterday and the bike started "smoking". It had been fine for several hours of riding and then we got stuck in some traffic we we noticed the smoke. A friend I was with said it seemed like exhaust fumes, and it certainly smelt like that, I was getting a nice amount of it in my helmet . We got home fine and took a closer look. We discovered the fumes were coming from the air box.

My friend thought this was very weird, said it could need a valve adjustment? I have also just taken off the carbs and given them a good clean, its idling MUCH better than it was. Could I have put something back wrong?

I would appreciate any help for this newbie bike owner!

Thanks in advance.

 

It is always a good idea to perform regular maintainence. 


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It may be blow-by from the valve cover breather hose that gets routed to the top of the airbox.
That's the way it was on my 81 KZ440.
Your's may be slightly different.

I disconnected the hose from the airbox.
Plugged the fitting on the airbox.
Ran the hose down by the swing arm pivot. Aiming at the ground.