Condensation from aircleaner

1971,750
I have a K&N style air filter. One of the two into one styles that filters both carbs. Stock Amals.
I am seeing drips of water come from the air cleaner. Not a lot but enough to drip. Bike is hot. What am I seeing?

MikeM said:

1971,750
I have a K&N style air filter. One of the two into one styles that filters both carbs. Stock Amals.
I am seeing drips of water come from the air cleaner. Not a lot but enough to drip. Bike is hot. What am I seeing?

Click to expand...

Do you have the oil tank vent running into the air filter?

comnoz said:

MikeM said:

1971,750
I have a K&N style air filter. One of the two into one styles that filters both carbs. Stock Amals.
I am seeing drips of water come from the air cleaner. Not a lot but enough to drip. Bike is hot. What am I seeing?

Click to expand...

Do you have the oil tank vent running into the air filter?

Click to expand...

No, but now that I think about it, it may be connected to the OE backing plate which is still mounted to the bike. It may be coming from the tube. I have to look into that. So it could be venting from the oil tank?

MikeM said:

comnoz said:

MikeM said:

1971,750
I have a K&N style air filter. One of the two into one styles that filters both carbs. Stock Amals.
I am seeing drips of water come from the air cleaner. Not a lot but enough to drip. Bike is hot. What am I seeing?

Click to expand...

Do you have the oil tank vent running into the air filter?

Click to expand...

No, but now that I think about it, it may be connected to the OE backing plate which is still mounted to the bike. It may be coming from the tube. I have to look into that. So it could be venting from the oil tank?

Click to expand...

You bet,
The air coming from the tank vent is just blowby that has made it by the rings. Blowby is exhaust gas which is super-saturated with water. Jim

That would make every bit of sense. The water is on the backing plate. Do I need to fit a breather style filter to it? Is it normal to have moisture there?

MikeM said:

That would make every bit of sense. The water is on the backing plate. Do I need to fit a breather style filter to it? Is it normal to have moisture there?

Click to expand...

Yes, it's normal for the water to condense from the blowby as soon as it gets to something cooler than the crankcase and oil tank.

I run a tiny K&N filter on the end of my tank vent hose. I don't think it's real necessary but I always liked the idea of keeping dirt and bugs out of there. Jim

MikeM said:

Do I need to fit a breather style filter to it?

Click to expand...

I have the same filter, and added a barb fitting into the rear air filter panel. The oil tank breather then vents into the "clean" air inside the filter. This also doubles as a poor man's emissions control, as any unburned fuel and/or oil vapours are drawn into the engine to be burned. Keep in mind that oil is terrible about dropping the octane rating of fuel, so, if you have problems with pinking, you probably shouldn't go this route. My big-ol' 850 doesn't seem to care, presumedly due to its lower compression.

Nathan