Hello from a n00b to the site - just got a new-to-me '09 S40 and we're making friends.  I've been reading a lot here and probably have missed this but here's my question... is there any benefit to adding a K&N filter without any other mods?  Or would it just be expensive and not have much affect?

I know backfiring is somewhat normal and especially the way I'm still learning how to operate this poor bike.  I just wondered if the filter alone would help (aside from me learning how to treat the throttle, I mean  )

Thanks!

No it wouldn't.
1st it'll make it leaner unless you rejet.
I recommend you leave it as it is for awhile.
maybe get together with some other savages so they can give you some tips.

Food for thought,.................
In a replacement filter, if there is less sg inches of filter surface, and less restriction than the stock filter, it means only one thing, it will ingest dirt.
IMO, the only safe way to get less restriction, is to increase the sq inches of filter surface.
If there was any restriction w/ the stock filter, (and I doubt there is) it would be at WOT only. Think about it,.....if there was any restriction at crusing speed, (1/2-2/3 throttle) what would happen at WOT using twice as much air ?