K&N Replacement Air Filter for the OEM Filter.

[MDO]

Tomorrow, I am picking up a K&N air filter to replace the OEM stock filter.

I still have everything else stock in the intake/exhaust system, so I will see how it effects the performance.

With my weather, I may not get much chance to evaluate any changes till spring.

I will post any info I get.

[firebikerd]

I was always told the stock air cleaner flowed just fine! I have the 2015 Freewheeler. I installed the DK 606 air cleaner with the remote breather and took it out for a test run. Wow what an increase in the seat of the pants torque and HP! Stock AC cover and no more hot oil in the Intake! Best bank per buck$!

Supposed to run cooler too but I can't prove that!?

[MDO]

I was always told the stock air cleaner flowed just fine! I have the 2015 Freewheeler. I installed the DK 606 air cleaner with the remote breather and took it out for a test run. Wow what an increase in the seat of the pants torque and HP! Stock AC cover and no more hot oil in the Intake! Best bank per buck$!

Supposed to run cooler too but I can't prove that!?

I want to get that remote external breather system, but have to pay off Xmas 1st.

I am not convinced that the new 107 cu.in. M8 has the same breather issues that the twin cam motor did. I run my bike at full oil capacity(full hot on dipstick) & have checked twice & seen no oil in the filter area.

I will check again when I install the K&N today. I plan on washing the stock OEM filter & keeping it for when I have to service the K&N.

[MDO]

There will be a delay in this test as the dealer ordered the wrong filter.

[rhino 2]

I want to get that remote external breather system, but have to pay off Xmas 1st.

I am not convinced that the new 107 cu.in. M8 has the same breather issues that the twin cam motor did. I run my bike at full oil capacity(full hot on dipstick) & have checked twice & seen no oil in the filter area.

I will check again when I install the K&N today. I plan on washing the stock OEM filter & keeping it for when I have to service the K&N.

I Keep the oil level at 3/4 of the way up....17 M8 107... and no blow-back...That said i don't need to run the 107 up into the high RPM range like i had to do with the 103 i had [62 hundred]....The 107 is much more powerful box stock than my 103 was with true-duels and stage 1 and a few other tweaks...

[Jack Klarich]

The HD motors pretty much ALL breath the same

That said the harder you ride expect a bit of oil mess ( constant high speed riding) will puke a bit more oil

Keeping the oil a bit down on the stick will help some

[DK Custom Products]

I want to get that remote external breather system, but have to pay off Xmas 1st.

I am not convinced that the new 107 cu.in. M8 has the same breather issues that the twin cam motor did. I run my bike at full oil capacity(full hot on dipstick) & have checked twice & seen no oil in the filter area.

I will check again when I install the K&N today. I plan on washing the stock OEM filter & keeping it for when I have to service the K&N.

The backplate of the factory 2017 M8 Air cleaner is very restrictive. One can keep the factory cover, but use a set up (like the 606) that will allow for the deletion of the restrictive OEM backplate.

The filter element of the OEM A/C is also very restrictive.

Feeding hot (oily or not) oxygen depleted air into the intake is a power & MPG robber.

Here is a 2017 M8 Freewheeler on the dyno...one run shows it bone stock, the next shows it with only a True High Flow Air Cleaner swapped out.



The increase is significant, and is definitely felt in daily riding...partly from the element, partly from the EBS and partly from the deletion of the restrictive backplate.

These three individually may not be felt by themselves, but there is a synergistic effect when doing all three.

DK Custom A/C Systems LINK

Kevin

[ultrafxr]

The backplate of the factory 2017 M8 Air cleaner is very restrictive. One can keep the factory cover, but use a set up (like the 606) that will allow for the deletion of the restrictive OEM backplate.

The filter element of the OEM A/C is also very restrictive.

Feeding hot (oily or not) oxygen depleted air into the intake is a power & MPG robber.

Here is a 2017 M8 Freewheeler on the dyno...one run shows it bone stock, the next shows it with only a True High Flow Air Cleaner swapped out.



The increase is significant, and is definitely felt in daily riding...partly from the element, partly from the EBS and partly from the deletion of the restrictive backplate.

These three individually may not be felt by themselves, but there is a synergistic effect when doing all three.

DK Custom A/C Systems LINK

Kevin

So for comparison the pulls were made with the same stock tune. But wouldn't the addition of a free flowing A/C require a tune to avoid a lean run condition? Not sure the ECM could compensate.

[MDO]

The backplate of the factory 2017 M8 Air cleaner is very restrictive. One can keep the factory cover, but use a set up (like the 606) that will allow for the deletion of the restrictive OEM backplate.

The filter element of the OEM A/C is also very restrictive.

Feeding hot (oily or not) oxygen depleted air into the intake is a power & MPG robber.

Here is a 2017 M8 Freewheeler on the dyno...one run shows it bone stock, the next shows it with only a True High Flow Air Cleaner swapped out.



The increase is significant, and is definitely felt in daily riding...partly from the element, partly from the EBS and partly from the deletion of the restrictive backplate.

These three individually may not be felt by themselves, but there is a synergistic effect when doing all three.

DK Custom A/C Systems LINK

Kevin

OK Kevin. I know I bothered you about this before & I am getting old.

1. I am picking up a K&N air filter (HD-1717) to replace the stock filter tomorrow.

I like the look of the stock 107 M8 air cleaner cover & want to use it.

2. I was going to order your EBS system & install it with the K&N.

Is there a better way to achieve my goal at the same cost? Is it possible to modify the OEM backplate so it's less restrictive?

I am open to suggestions?

Thanks, Michael

[Jack Klarich]

OK Kevin. I know I bothered you about this before & I am getting old.

1. I am picking up a K&N air filter (HD-1717) to replace the stock filter tomorrow.

I like the look of the stock 107 M8 air cleaner cover & want to use it.

2. I was going to order your EBS system & install it with the K&N.

Is there a better way to achieve my goal at the same cost? Is it possible to modify the OEM backplate so it's less restrictive?

I am open to suggestions?

Thanks, Michael

Michael I can speak from doing this

It aint wort it to modify the plastic back plate

The ones Kevin sells are tried and true

The Dyno sheets you see are from my Freewheeler

I would suggest you get with him, I believe you can get the back plate form him seperate, BUT I dont think the HD K N filter will work

In fact from the dyno pulls Kevin used ALL the filters including the front facing one, The Outlaw ( smaller round one) out performed them all

JMO

[DK Custom Products]

So for comparison the pulls were made with the same stock tune. But wouldn't the addition of a free flowing A/C require a tune to avoid a lean run condition? Not sure the ECM could compensate.

Unlike the Twin Cams, the M8's that we've tested do NOT run lean from the factory!

That is not to say that the tune can't be optimized...but it is more timing than AFR changes, since HD got the AFR nailed pretty good stock.

All the dyno charts on the subject can be seen in this REPORT.

Here's just one chart to illustrate...look at the report to see all the info and charts.

Shows the AFR hovering between 12 & 13 WOT with the stock tune and the HiFlow 587. (a Twin Cam would be bouncing between 16 & 17, far too lean)



Kevin

[DK Custom Products]

OK Kevin. I know I bothered you about this before & I am getting old.

1. I am picking up a K&N air filter (HD-1717) to replace the stock filter tomorrow.

I like the look of the stock 107 M8 air cleaner cover & want to use it.

2. I was going to order your EBS system & install it with the K&N.

Is there a better way to achieve my goal at the same cost? Is it possible to modify the OEM backplate so it's less restrictive?

I am open to suggestions?

Thanks, Michael

Hi Michael,

Not sure how much you are paying for the filter element, so I can't address "same cost" part of your question.

You can cut away big chunks of the OEM plastic backplate, and combining that with the new filter element and an EBS will be an improvement. It will not be as much as an improvement (power or MPG) as getting the HiFlow 606, which is made to use the factory cover...but it probably is a bit less expensive.

Michael I can speak from doing this

It aint wort it to modify the plastic back plate

The ones Kevin sells are tried and true

The Dyno sheets you see are from my Freewheeler

I would suggest you get with him, I believe you can get the back plate form him seperate, BUT I dont think the HD K N filter will work

In fact from the dyno pulls Kevin used ALL the filters including the front facing one, The Outlaw ( smaller round one) out performed them all

JMO

Hey Jack. I agree, the cost difference is relatively small, and the benefits are significant.

I don't think we every posted a video of any of the dyno time with your Freewheeler...I'm going to look and see if I can't find one and post it up.

Kevin

[Jack Klarich]

Hi Michael,

Not sure how much you are paying for the filter element, so I can't address "same cost" part of your question.

You can cut away big chunks of the OEM plastic backplate, and combining that with the new filter element and an EBS will be an improvement. It will not be as much as an improvement (power or MPG) as getting the HiFlow 606, which is made to use the factory cover...but it probably is a bit less expensive.

Hey Jack. I agree, the cost difference is relatively small, and the benefits are significant.

I don't think we every posted a video of any of the dyno time with your Freewheeler...I'm going to look and see if I can't find one and post it up.

Kevin

Dont show him the Wheelie, He may like it

I know from the seat of my pants the Outlaw air cleaner set up is WAY better than any screaming eagle set up PLUS I know that oily water mess oil is NOT in my intake

When IO did use a screaming Eagle set up I rerouted the head breathers I knew that mess woul carbon up and over time the compression ratio would slowly change YUK

[MDO]

Thanks for the information. I paid $68 for the K&N p/n HD- 1717.

I got home with it late after a fantastic 100 mile ride & got it installed, but no test ride.

A couple things I noted after 4,600 with the OEM air cleaner. 1/2 of that milage was highway from CA back to MO at 70-75mph.

I keep my oil level to the full hot line all the time. I found the air cleaner/intake area very clean with 2 drops of clean oil at the intake to the throttle body. Like someone had taken their finger & dipped it in clean oil & touched by the intake. The bottom front of the stock filter was slightly dirty on the outside, but not excessive. The surface area of the K&N is probably 60-70% bigger than the stock filter.

When I can get a decent ride in, I'll let you all know what I think.

[Jack Klarich]

The bottom front of the stock filter was slightly dirty on the outside, but not excessive. The surface area of the K&N is probably 60-70% bigger than the stock filter.

That would be the low point of the filter, a good place for the head breather oil to gather

Your bike is doing good, not having much oil in the intake

Over time as the engine wears some and at high speed hiway riding the oil in the filter will be a bit more

It is nature of the beast the way a Harley engine breaths

You will be WAY better ahead with out that gunk going in your engine

Take a look in the intake of your car or truck

They breath the same or close to the same as your Harley

This could explain a touchy accelerator or even a choppy idle JMO

Way back in the 70s we started venting the Shovelhead Harleys for this same reason

Plus we wanted to get the pressures in the crank case equal a lot faster for a better running engine

[MDO]

I should be able to get a ride in tomorrow & will let you know what I think.

Our weather is getting bad after that, so this may be my last fling for awhile.

[Jack Klarich]

I should be able to get a ride in tomorrow & will let you know what I think.

Our weather is getting bad after that, so this may be my last fling for awhile.

Your K N will make you happier than stock

This is 1 of the first things i always do to my bikes

The surface area is more PLUS IMO it is better construction

Even if I don't service it @ the right times I know it is still doing its job

Happy riding and Merry ChristmasPS I always over oil them, I dunno why Dont be alarmed if it smokes a bit from TOO much oiling

This will clear up

I know they come pre oiled I cant help my self @ times

[MDO]

I just got back from a 75 mile ride with the new K&N & there's a definate difference & in a good way.

I spend a lot of time in the 2500 to 4000 rpm range & the throttle response is definitely improved in that range.

I also did a couple tests looking for a lean condition (popping on deceleration) & found none.

The new K&N was well oiled & pink when I unbagged it so, sorry Jack, I left it alone.

A nice ride at 55 & sunny, not bad for the 1st. day of winter. I love my Freewheeler, it runs better every time I get on it!

Merry Christmas everybody.

[DK Custom Products]

I just got back from a 75 mile ride with the new K&N & there's a deffinate difference & in a good way.

I spend a lot of time in the 2500 to 4000 rpm range & the throttle response is definitely improved in that range.

I also did a couple tests looking for a lean condition (popping on deceleration) & found none.

The new K&N was well oiled & pink when I unbagged it so, sorry Jack, I left it alone.

A nice ride at 55 & sunny, not bad for the 1st. day of winter. I love my Freewheeler, it runs better every time I get on it!

Merry Christmas everybody.

Glad you were able to get out and ride! Yes, the M8 wants to breathe...and by changing out that stock filter, you are giving it a bit more air now and it is thanking you with some extra power.

btw, 99 times out of 100, decel pop is Not an indication of a lean condition. That is a very popular myth.

Decel pop is normal for a bike with open exhaust and open A/C that has a performance tune.

Decel popping does Not damage your engine...it is simply unburnt fuel that is burning in the exhaust tract after exiting the engine.

Lots of folks don't like the decel pop and try and tune it out.

Decel popping occurs when one of two things are present.

1. The bike is so lean the exhaust is superheated and is burning the unburnt fuel that is in the pipes (there is always some unburnt fuel in the pipes no matter how lean). This is very rare.

2. The AFR IN THE pipes is just right to burn the unburnt fuel. This is quite a common occurrence when free flowing pipes are installed (whether or not a free flow A/C is installed). It can also occur if there is an exhaust leak that is introducing extra air into the exhaust tract.

Most stock mufflers will mask, or nearly mask, decel pop. Also, stock mufflers are quite choked down, so usually the AFR in the exhaust does not have enough air to mix with the un-burnt fuel allowing it to burn.

Lots of folks don't like the sound of decel pop, so they try various strategies to reduce/eliminate it.

To get rid of decel popping a lot of people put MORE fuel than is needed into the engine/over-richening the AFR so that more unburnt fuel goes into exhaust, changing the AFR in the exhaust so that is no longer optimum for combustion in the pipes. This is just a waste of gas. And if using decel enleanment found on most tuners it is still really hard (but possible) to get rid of the popping/burbling when the injectors kick back in at about 1750 rpm.

But these strategies will almost always come with a sacrifice of power and/or MPG.

Bottom line, decel pop is very rarely a result of a too lean condition, and it is almost always present in a proper tune with free flowing pipes.

Kevin

[MDO]

Thanks Kevin.

I learned something today from your post.

I'm only 1/2 as smart as I think I am.