What's this crap? Airbox drain pipe
 

https://dl.dropboxusercontent.com/u/...wImage0002.jpg

Removed the plug from the drain pipe and this pile of oil and what looks like Birdsh*t poured out.

Inside the airbox was clean, but a considerable pool of oil at the bottom. (clean oil, I should add)


Am I right to assume its just some emulsified oil (mixed with road gunk and water) just lurking in the drain pipe?
There was no evidence of the 'birdsh*t' in the air box, just in the drain pipe.

Yep. Perfectly normal. The vast majority of this crap is oil from the crankcase which is blown out as mist through the breather. A tiny proportion is condensed water vapour from atmospheric air.

Older Teneres (08/09) were much worse for collecting oil in the airbox particularly during sustained high speed riding on motorways etc. Yamaha changed the catch tank baffling to try and reduce the amount of oil mist blown into the airbox by trapping more in the catch tank which then drains back into the crankcase.

Even with later models, and early ones that had the later catch tank fitted under warranty, still blow a reasonable amount of oil through on long runs at higher engine speeds.

It always looks more than it is. I've measured it, and a full tube, backed up to the bottom of the airbox, only holds 20ml.

Ah, that'll be it then!