What is the difference between stage 1 and stage 2 air cleaners? I saw one on Arlen Ness that is a stage 2 and ones that are stage 1. I would like to understand the difference.


Also, my RKC (2012) is pretty stock. If I change the air cleaner do I need to retune the bike? My plan over time is to change out the air cleaner, headers and pipes, but this will be phased approach as finances permit.


Thanks

 

Stage 1 is air cleaner and exhaust, stage 2 is cams and pushrods, stage 3 is big bore and stage 4 is heads and fuel system upgrades.

No, you don't need a tune for air cleaner only. I'd do one after pipes.

 

I grabbed this off the Arlen Ness Website, this is why they say they offer different options.

BIG SUCKER STAGES:

Big Sucker Air Cleaner kits are available in 3 stages: Stage 1, Stage 2, and Derby Sucker
Stage 1 kits give the option to use either your OEM air cleaner cover or to install an Arlen Ness custom cover
Stage 2 kits feature a 20% larger filter element over Stage 1 for even more airflow and require the use of a custom outer cover
Derby Sucker kits feature a 20% larger filter element over Stage 1 and allow the use of any 5-hole derby cover

Some companies ( like us for example) do not have different Air Cleaners for different stages, because all of our Air Cleaners flow more air than your motor can eat.

As far as a tune, you asked if you need to "retune". Do you already have some sort of fuel management? The general rule is, you can change EITHER your exhaust OR air cleaner and be fine. It is only when you change BOTH that you HAVE to get some sort of fuel management. Below is a link that goes into much more detail and you might find helpful.

CLICK ME

 

Sounds like Arlen Ness has created their own definition of air cleaners. The stage two label is definitely misleading since this term is generally associated with cam changes. You need not be concerned about air flow since all the aftermarket air cleaners flow plenty. Just get the set-up that appeals to you most cosmetically.

 

People use these terms differently. My advice is to save up and then do it all together and get it tuned once. Will be cheaper in the long run than doing it piecemeal. Hiflo air cleaner, headers and mufflers and a good mid range cam with a fuel management system professionally tuned.