I've recently become a bit paranoid about the recycling of hot, oily air from the rocker covers into the air intake, and so I'm looking to replace the AN Big Sucker on my fatboy with something that has a backing plate which allows the use of external breathers. The DK Customs air cleaners look like a good option.

But there's 4 different model numbers! I don't like the look of the 636 (looks like the screaming eagle one with the right-hand bend and the "cone in the wind"). But all the other three models look fairly similar.

Which of them gives the best performance, and if it's all pretty similar, are there any that can reuse the filter from my Big Sucker?

Thanks everyone for your help

 

Call them. Kevin and them are great to talk with. They won't make you feel like an idiot. I think you're filter from the BS is the same one they use. HD-0800. They all do perform about the same and will allow more air than your engine can use.

 

The 587 will provide your engine all the air it can use. You say the 636 is out; I don't blame you The velocity stacks and the 425, depending on your engine build state may not provide enough air for your Twin Cam at higher RPM's; I liked the smaller physical size of the 425 but chose the 587.

This is the 587 on my Wide Glide with the smooth chrome bobber cover, externally venting. I have a couple K&N filters for the 587 so the spare filters are always clean, oiled, and ready to go. Great build quality and I'm a permanent DK Custom customer