More Air - More Ping

[deejay-2k]

Hey Mike,

I recently replaced my SE AC on my 93 FLHS with an Arlen Ness Stage II Big Sucker. Since then I have had a lot more pinging. I tried octane booster which helped only a little. I retarded the timing which also helped a little, but the ping still exists and the performance is crap. Did I just thoroughly screw up the AFR by going with a larger filter? I'm guessing I may need a larger pilot and/or main jet on the Mik 42 and another dyno tune in order to keep the new AC and restore performance. :(

Here is my info:
81" EVO w/ SE Baisley Heads
SE Forged Pistons w/ 10.5:1 CR
Woods W6H cam & Rivera TaperLite Pushrods
SE Single Fire Adj Ign Mod & SE Coil
Mikuni HSR42 w/ 150 Main Jet
SuperTrapp TD's w/ 18 discs each & Fishtail SO's

[Mike]

Normally the Ness Big Sucker really does not move much (if any) more air than the SE (especially on a 81ci motor). Two things come to mind, 1. the SE was really dirty and the bike was tuned to this and the new, clean filter corrected this situation. 2.(more likely) the old air cleaner vented the head breathers to the bottom of the air cleaner and so the carb saw very little of the oil mist from them. The Ness air cleaner directs this straight into the carb and this added oil may be diluting the fuel, causing the ping. Venting the breathers to the atmoshpere may help, but not easy to do with the Ness unit. Acclerator pump, needle and low speed jet adjustments may be required, along with timing. The main jetting should be done with use of a dyno.