Frei nach Keith Calver, der vor einigen Jahren mal einen Smallbore-Motor mit einem offenen K&N vs. das bearbeitete Originalgehäuse getestet hatte und herausfand, dass das Gehäuse leistungmäßig mit K&N-Einsatz besser abschneidet.
The standard air filter casing is surprisingly effective and efficient. Utilizing
this with a replacement K&N air filter will provide pretty much all the airflow the engine will need, even when fairly well tuned. All that is needed to
maximize the performance is to remove the hot-air 'snorkel', and drill a half-dozen three-quarter-inch diameter holes around the front underside of the casing. Ensuring these holes are OUTSIDE the cleaner element of course! The bonus of retaining the standard casing is the civilized noise level it provides in comparison to the cone/pancake type K&N…It may look prettier - but that cone/pancake makes a mighty row. It's OK at idle, and tolerable when cruising at low speed, but any load or high- speed motoring creates an ear-bleeding din. Not only that, sorting the fuelling can be very arduous, AND recent testing has proven that this et-up actually LOOSES power over the aforementioned by around 5%! Now that's definitely not good.
So sieht das bei dem Vergasercoopergehäuse aus:
6 schöne 3/4 Zoll (~2cm)-Löcher auf der "Frischluftseite" unten am Gehäuse.
Bei meinem Alltags-1000er bewirkt die Maßnahme mindestens den "addictive Sound" - echt nah am Weber!
