Recently I had the open cone air filter fitted on my Speedster Turbo when I bought it replaced with the original filterbox. Being my commuter ride it was simply a little too... noisy...
First impression was sort of "what the heck happened to the sound, -everything almost gone, sounds more civilized like a family car", -and then of cause I could hear a bunch of new rattles etc.
The engine seemed to run more smoothly as the "coughing" it could have under moderate to high load at 2500-3000 RPM was gone (guess there was some turbulence in the air duct with the open filter).
With the new sound track I also got my focus on something sounding like misfire on one cyllinder, or at least that was my hope, if mechanical I should probably start saving up some money for repair.
This morning I removed the col pack, and found it a little greasy/oily on two of the rubber tubes sticking out. I removed all of those, and cleaned inside and out with isopropyl alcohol, refitted, and now it just runs smoothly, and acceleration is much smoother than it used to be. Issue seems to have been caused by current leak inside the rubber tubes.
Now there is just all the rattles, but so far, I had a really enjoyable ride to work this morning 
-Søren
