I'm switching the stage 1 paper "synthetic media" filter on my '09 Rocker to the HD 0800 K&N filter since I prefer the oiled filter vs. the paper one--still wondering why Harley stopped offering the K&N for Stage 1.

That said, my dealer, Bumpus HD, tells me that I need to have my SERT reprogrammed again for the K&N since it flows more than the Stage 1 paper filter installed.

I had the race tune installed with my SERT when I had the Stage 1 and V&H Big Radius pipes installed. Bike runs perfect. Will the slight difference in air flow from simply switching filters make a difference in needing a re-tune? I'd imagine the slight difference in flow wouldn't necessitate a change as I already have the race tune with my pipes and Stage 1.

Thoughts?

Karl

 

I have the green hd filter also on my 103 build. I wouldn't think it would make a difference. I will be changing mine to K N will needed.

 

The K&N is a better flowing filter. But weather or not you need a re-tune depends on how it was tuned last time. Your bike will be a tad bit leaner than it was before. If it was real lean before than you could have some problems. If it was a little rich you could be alright. If you want to chance it, my advice would be to spend a few more bucks and get a new set of plugs so you can pull them out and inspect them to tell if your running to lean.

 

I switched out the paper SE filter for the same K&N filter.
I also had the SERT and SE slipons,std. download?,no dyno.
I did not notice any difference(except for a little better gas mileage) and ran it that way for over 25000 miles on the stock 88 with no problems.

 

I agree with harlytuner, your dealer perfers to error on the safe bet, just happens to be the costly one. Use the plug test and also listen for decel poping ect, then deside if you need it tuned.