Wow - this good information - I read the whole thread a few times and still a bit unsure...., I have an 04 BigDog Chopper, bought it used, previous owner had a K&N 171 on it for it's whole life (17K miles). It's an Evo, not sure if top end is Twin Cam type (never knew it could be). So should I dump the K&N 171 and just go with a K&P? Or at least switch to the K&N 170...?
Also, I have a 07 Harley Springer Softail (twin cam 96), sounds like I should run a K&P on that too, so......., maybe I can just run a K&P on both my bikes and don't have to worry about it anymore?