Stranger in a strange land
 
 

Well, I looked inside the airbox, and figured that while I was putting on the TBR exhaust and Factory jet kit (a nightmare - I ended up getting a local cycle shop to sort the jetting, as I don't have an exhaust gas analyser), I'd replace the original Honda air filter.

Now, in the UK, K&N make a filter specifically for the Hawk, (the part number is HA-0005). I'd used one of these to good effect on my Hawk in the UK... K&N filter, DynoJet kit and a Spec II pipe gave 51hp, not bad for a low revving twin. This isn't available in the US, so I had a friend in the UK order me one, and another friend carry it over for me in his luggage... cool.

The Honda filter fits fairly flush, and filters over the top, whereas the K&N item filters around the edge... an easy performance mod (or noise mod, depending on how you looked at it) was to cut holes in the top of the airbox (this was done on my UK Hawk when I got it, and I ended up taping up the holes as the carb roar was getting me down - call me old), but the K&N's top will block these holes up. It might make sense to run the airbox with the top off, but it cuts down on the noise with it on, so I do that.
I figure the air filter is about $100, give or take, depending on the exchange rate.