Anyone install an aftermarket air filter?

TodkaVonic

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Tonight I learned that the air filter isn’t exactly near the chrome “air box cover,” and removal of said cover isn’t required when accessing the filter. No, it’s an item which is accessed by removal of the engine cover. Because of course. I’m sure this isn’t news to many of you, but I couldn’t find hardly a peep about this on the inter webs (or here) and was genuinely curious.

5C18B93F-018E-4FF9-9401-B66B6FF9AEB0.jpeg
Thar she blows! Er, sucks!

So now onto the topic at hand: any advice regarding aftermarket filters? Waste of money? Inbound air passes down a pair of these wee tubes prior to reaching the filter.

13D86226-F02E-47F8-9175-CBBF5A0939C7.jpeg
BCDE16D5-8257-434D-8665-D3427D094DF4.jpeg
I’m thinking a marginally less restrictive filter will have little consequence. Any “Butt Dyno” experience with filter mods on other boxer engines?
 
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Tonight, I learned that the air filter isn’t exactly near the chrome “air box cover,” and removal of said cover isn’t required when accessing the filter. No, it’s an item which is accessed by removal of the engine cover. Because of course. I’m sure this isn’t news to many of you, but I couldn’t find hardly a peep about this on the inter webs (or here) and was genuinely curious.

View attachment 1783
Thar she blows! Er, sucks!

So now onto the topic at hand: any advice regarding aftermarket filters? Waste of money? Inbound air passes down a pair of these wee tubes prior to reaching the filter.

View attachment 1785
View attachment 1784
I’m thinking a marginally less restrictive filter will have little consequence. Any “Butt Dyno” experience with filter mods on other boxer engines?
Those 'wee tubes' are part of BMW's Intake Silencer to help appease EURO-5 noise levels, covering all noise produced by the bike in total - intake, engine, exhaust, etc.

Invariably, whenever one installs a less-restrictive air filter element or retrofits another air cleaner configuration, e.g. K&N pods (like on the FCR Bobber), it will be associated with some form of ECU 'assistance' like loading another tune/map or piggy-backing a Fueler. Precious little is available, remapping-wise, for BMW from TuneECU (TuneECU BMW tune list) or RapidBike, yet, (BMW - EVO | Rapid Bike fuel management systems with built in adaptive tuning.). Without that, one runs the distinct risk that the engine will run too lean, pre-igniting/detonating under certain conditions (although the R18 features a ping sensor), potentially spoiling fueling anywhere (even everywhere) in the rev-range and excessively popping when decelerating. And this is not something that HexCode's GS-911 is savvy enough to assist with - neither MotoScan for that matter.

Only DNA does a 'hot-swap' aftermarket filter at present - BMW R18 (20-21) DNA Air Filter P-BM18CR20-01 - OEM Air Filter Air Flow: 101.60 CFM, DNA Air Filter Air Flow: 124.30 CFM - BMW-R18 - DNA Filters - Product Details (e-dnafilters.com).

custom-bmw-r18-sport-edition-fcr-original-3.jpg
custom-bmw-r18-sport-edition-fcr-original-6.jpg
custom-bmw-r18-sport-edition-fcr-original-9.jpg
(photos courtesy BIKE-EXIF)
 
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Those 'wee tubes' are part of BMW's Intake Silencer to help appease EURO-5 noise levels, covering all noise produced by the bike in total - intake, engine, exhaust, etc.

Invariably, whenever one installs a less-restrictive air filter element or retrofits another air cleaner configuration, e.g. K&N pods (like on the FCR Bobber), it will be associated with some form of ECU 'assistance' like loading another tune/map or piggy-backing a Fueler. Precious little is available, remapping-wise, for BMW from TuneECU (TuneECU BMW tune list) or RapidBike, yet, (BMW - EVO | Rapid Bike fuel management systems with built in adaptive tuning.). Without that, one runs the distinct risk that the engine will run too lean, pre-igniting/detonating under certain conditions (although the R18 features a ping sensor), potentially spoiling fueling anywhere (even everywhere) in the rev-range and excessively popping when decelerating. And this is not something that HexCode's GS-911 is savvy enough to assist with - neither MotoScan for that matter.

Only DNA does a 'hot-swap' aftermarket filter at present - BMW R18 (20-21) DNA Air Filter P-BM18CR20-01 - OEM Air Filter Air Flow: 101.60 CFM, DNA Air Filter Air Flow: 124.30 CFM - BMW-R18 - DNA Filters - Product Details (e-dnafilters.com).

View attachment 1788
View attachment 1789
View attachment 1790
(photos courtesy BIKE-EXIF)
Helpful and knowledgeable as always Estoma.
 
It would be nice if a company did some real tests, with a dynamometer and the ability to remap the fuel injection and ignition systems. We've learned over the past DECADES that simply replacing enclosed intakes with K&N filters often causes a loss of performance, with the added expense of increased intake roar. Modern superbikes usually have HUGE air boxes because it benefits performance. Intake volume matters. So does low restriction to flow. It's gonna take a good tuner with the right equipment to develop real improvements over the OEM's design.
 
I have found those air cleaners DO flow better, they also let more dirt in. I don't think they do much for actual performance. The engineers go through a lot to tune the intake on a car truck or bike. Replacing the whole intake with a "free breathing" air filter could possibly only help on Top end wen the throttle is all the way open.

I feel the same way about exhaust.

Replace the muffler and re jet the carb. Big noticeable gain. 90% was from the re jetting and the rest is in your head because it "sounds better"

Those intake hoses and Air filter do the same as the exhaust. It sounds cool when you open the throttle up. but is there really a horse power gain?

I had a fuel spoofer on my R1100RT. It would make a difference in power. It worked for its intended purpose. The best thing about it was the "virtual accelerator pump". It increased the fuel when ever you turned the throttle Made a noticeable difference,

It always was on a car, do the intake (manifold), Camshaft and Exhaust to get a total flow package and increase horse power.

David

Wondering if BMW can tweak the R18?
 
Tonight I learned that the air filter isn’t exactly near the chrome “air box cover,” and removal of said cover isn’t required when accessing the filter. No, it’s an item which is accessed by removal of the engine cover. Because of course. I’m sure this isn’t news to many of you, but I couldn’t find hardly a peep about this on the inter webs (or here) and was genuinely curious.

View attachment 1783
Thar she blows! Er, sucks!

So now onto the topic at hand: any advice regarding aftermarket filters? Waste of money? Inbound air passes down a pair of these wee tubes prior to reaching the filter.

View attachment 1785
View attachment 1784
I’m thinking a marginally less restrictive filter will have little consequence. Any “Butt Dyno” experience with filter mods on other boxer engines?
What were the steps required to remove that cover to get to the Air Cleaner? I temoved the after cover and surprise, there wasn't an Air Cleaner to be found.
 
What were the steps required to remove that cover to get to the Air Cleaner? I temoved the after cover and surprise, there wasn't an Air Cleaner to be found.
Haha! Yeah, me too!

Here are the steps

1) remove 1800cc emblems.
2) remove screws under emblems. There are two on each side.
3) remove the two screws which hold the left and right engine cover pieces together. They’re accessible from the left side. They're tucked way under there.
C70F98E2-F841-4A06-90C7-EB24A04B8B8E.jpegFront
4A138C13-7F6B-43C8-8427-D5D06E41846F.jpegRear. Don't over-think how to put it back. Just get it up into that runway and advance, it'll seat.

4) now that they’re unattached, the engine cover pieces need to be gently lifted towards the gas tank off of a pair of guide pins onto which they’re positioned. There are no pins between left and right pieces.
A85E3198-D41A-46EB-8C5C-DFD974521205.jpegPins

5) you’re now looking at the filter assembly.
05E88360-3CA2-4463-8B40-F99F7A8F378D.jpeg

To access the two screws at the front of the filter cover, you need to remove the wee plastic intake tubes. I found that the easiest way to do this was to grab it at the accordioned part and pull, somewhat forcibly, out. Repeat on the other side then remove the 4 screws holding the cover in place.

6828CA62-ACE1-4F99-A8ED-302DD53D51CD.jpegScrew under wee tube

That’s it!

****Tip on reassembly: 1) the plastic intake tubes are fairly tedious to reposition. I put the forward part into it's recess first then bent the accordioned bit towards me (mimicking the extraction procedure) and basically shoved the rearward part back into place. The rearward part of the tubes feel somewhat more malleable and this worked better than other methods I attempted. 2) it feels like best practice to thread the two screws holding the left and right engine cover pieces back together first, then the screws under the 1800cc emblems, then, once they're all in place, to tighten everything firmly. 3) I didn't see any loctite on any of the screws I removed so I didn't apply any for reassembly.
 
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Those 'wee tubes' are part of BMW's Intake Silencer to help appease EURO-5 noise levels, covering all noise produced by the bike in total - intake, engine, exhaust, etc.
Only DNA does a 'hot-swap' aftermarket filter at present - BMW R18 (20-21) DNA Air Filter P-BM18CR20-01 - OEM Air Filter Air Flow: 101.60 CFM, DNA Air Filter Air Flow: 124.30 CFM - BMW-R18 - DNA Filters - Product Details (e-dnafilters.com).

That DNA filter comes in two varieties: with a bracket to hold it in place in lieu of the oem plastic air filter cover, and without. The bracket exposes the lions share of the surface and negates the possibility of reassembly with the wee plastic intake tubes. Anyone wanna give it a go?
 
I have found those air cleaners DO flow better, they also let more dirt in. I don't think they do much for actual performance. The engineers go through a lot to tune the intake on a car truck or bike. Replacing the whole intake with a "free breathing" air filter could possibly only help on Top end wen the throttle is all the way open.

I feel the same way about exhaust.

Replace the muffler and re jet the carb. Big noticeable gain. 90% was from the re jetting and the rest is in your head because it "sounds better"

Those intake hoses and Air filter do the same as the exhaust. It sounds cool when you open the throttle up. but is there really a horse power gain?

I had a fuel spoofer on my R1100RT. It would make a difference in power. It worked for its intended purpose. The best thing about it was the "virtual accelerator pump". It increased the fuel when ever you turned the throttle Made a noticeable difference,

It always was on a car, do the intake (manifold), Camshaft and Exhaust to get a total flow package and increase horse power.

David

Wondering if BMW can tweak the R18?
The latest motorcycle engines are super-refined and very efficient. They are actually simply terrific, especially fueling and performance-wise, when compared with those of even just a decade ago. Engine clearances are minimal, tolerances low and quality control devoid of operator latitude. Ducati switched its air-cooled Monster range to obnoxiously plumbed water-cooled engines (especially when viewed from the left) in 2013 because it believed air-cooled engines could not meet post-EURO-4 requirements while still delivering satisfactory performance levels. Mainly since those invariably run hotter and require larger clearances, resulting in more blowby and worse emission levels. It is, therefore, all the more remarkable that H-D and BMW still managed to bring new large air-cooled (slash-oil-cooled) engines to market that meet EURO-5 - the M8 and R18. I am not sure about EURO-6 on the horizon, 'but let's see what happens'.

The latest motorcycle airboxes are very efficient plenum chambers, capitalizing on the ram-air effect to achieve nett positive pressure while optimizing airbox size and shape, internal velocity stack lengths and throttle body diameters to sustain it. Much of this is achieved using CFD (computerized fluid dynamics), and gone are the days of thinking that big performance increases can be had by simply throwing on K&N pod filters and open (exhaust) pipes.

I am convinced that a less restrictive aftermarket air filter and matching tune (or piggybacked tune) will see better performance from the R18 - simply because EURO-5 runs the engine as lean as absolutely possible and even trims throttles (and top speeds) back. But we need DimSport® (RapidBike) or DynoJet® (Power Commander 5 / Power Vision 3) to come to the party first. And that will require many more R18's to be sold.

One is obviously welcome to visit your local 'dyno guy', but the chances are good that yours will be the first R18 or even BMW boxer he sees and that the outcome could be dicey, also reliability-wise, apart from providing him with a prepaid training opportunity (-;
 
That DNA filter comes in two varieties: with a bracket to hold it in place in lieu of the oem plastic air filter cover, and without. The bracket exposes the lions share of the surface and negates the possibility of reassembly with the wee plastic intake tubes. Anyone wanna give it a go?
The latest ECUs all feature adaptive capabilities to various extents, depending on how the OEMs specified it. You can install an open air filter on most new KTM or Triumph models, start the engine without touching the throttle and allow it to idle - 15 minutes for a KTM and 12 minutes for a Triumph after the fan(s) started running - and it will self-adapt. Not so for BMW - which is why RapidBike® sales are sky high for GSs and S1000RRs. The R18 might be different - it does feature a ping sensor to detect preignition, but that might only retard timing in response instead of enriching (God forbid) the mixture. This could skew the results, making it seem that the aftermarket air filter did not improve things much.

In the (not so) good old 'carburettor' days, we would run the engine at a certain throttle opening for a bit, throw the kill switch, coast to a standstill and check how the spark plugs were burning. Not so easy, or simple, anymore. So, I will sit it out for now - and watch the first adopters (-:
 
The latest ECUs all feature adaptive capabilities to various extents, depending on how the OEMs specified it. You can install an open air filter on most new KTM or Triumph models, start the engine without touching the throttle and allow it to idle - 15 minutes for a KTM and 12 minutes for a Triumph after the fan(s) started running - and it will self-adapt. Not so for BMW - which is why RapidBike® sales are sky high for GSs and S1000RRs. The R18 might be different - it does feature a ping sensor to detect preignition, but that might only retard timing in response instead of enriching (God forbid) the mixture. This could skew the results, making it seem that the aftermarket air filter did not improve things much.

In the (not so) good old 'carburettor' days, we would run the engine at a certain throttle opening for a bit, throw the kill switch, coast to a standstill and check how the spark plugs were burning. Not so easy, or simple, anymore. So, I will sit it out for now - and watch the first adopters (-:
Any worry that the warranty wouldn't be honored should the air filter assembly be modified? What about just swapping the filter for the DNA one?
 
Any worry that the warranty wouldn't be honored should the air filter assembly be modified? What about just swapping the filter for the DNA one?
ANY modification or non-OEM change to the bike can be uased as a reason to refuse warranty work if said modification or non-OEM alteration or parts can be reasonably argued to be the cause of the issue. So, changing to a non-stock intake or alternative tune can not be used to refuse a warranty claim for a suspension problem or a drive system issue. But if the bike runs badly or suffers a scored cylinder and it can be reasonably argued that the non-OEM changes may have caused the problem, then that particular warranty claim can be denied.
 
Any worry that the warranty wouldn't be honored should the air filter assembly be modified? What about just swapping the filter for the DNA one?
At worst, the 'drive malfunction warning light' will light up on the speedo, and the ECU might log a 'soft' error code, but one should be able to clear it with the GS-911 or MotoScan. I've not seen that happen with an air cleaner swap yet, though. Swap the stock filter back the weekend before taking it in for a service. The dealer should be none the wiser if the ECU is savvy enough to adapt to an increase or decrease in air filter efficiency, which normally takes no longer than 300 km (roughly 200 miles).
 
Any worry that the warranty wouldn't be honored should the air filter assembly be modified? What about just swapping the filter for the DNA one?
Hmmmmm... I've already replied to TV's question. But I wonder why folks worry about the warranty when talk is about swapping the air filtration parts, but nobody wonders about it when the talk is about swapping the exhaust system components.
Not wanting to start any contentious backlash. I'm just curious.
 
I did the K&N drop in and left off the intake tubes.
 
I installed a dna with their cover.

1) remove the 1800 plate from each side
2) remove the two obvious vertical screws from each side your can see after removing the 1800 plates
3) go to the lhs of the bike to remove the top half of the engine cover providing access to the filter. To do so, remove the grey side covers on each side by removing the two horizontal screws from the lhs that are just under the fuel tank. These hold the two sides together. (With the bike fully assembled you can see these with a flashlight. )

4). Yank out the plastic snorkels.

5) remove the 4 bolts holding down the filter assembly and pull out.

5) screw in dna assembly.

There is no ram effect through these snorkels. The intakes are located behind the front tire and then behind the breast plate. Super convoluted path. There is no clean air to ram anything. It is sucking.

3) my experience with snorkels like this is that when it is time to change your air filter you will be shocked that the only dirty part is right under the snorkel. Hence only about 5% of the filter area is being used for air intake with these.

The dna system is wide open. Yes it has vast more surface area, but I doubt the bike needs all of the area provided no matter what you do to the exhaust or fueling. (Simply conjecture). But more area is better than less in this set up.
 
The latest motorcycle engines are super-refined and very efficient. They are actually simply terrific, especially fueling and performance-wise, when compared with those of even just a decade ago. Engine clearances are minimal, tolerances low and quality control devoid of operator latitude. Ducati switched its air-cooled Monster range to obnoxiously plumbed water-cooled engines (especially when viewed from the left) in 2013 because it believed air-cooled engines could not meet post-EURO-4 requirements while still delivering satisfactory performance levels. Mainly since those invariably run hotter and require larger clearances, resulting in more blowby and worse emission levels. It is, therefore, all the more remarkable that H-D and BMW still managed to bring new large air-cooled (slash-oil-cooled) engines to market that meet EURO-5 - the M8 and R18. I am not sure about EURO-6 on the horizon, 'but let's see what happens'.

The latest motorcycle airboxes are very efficient plenum chambers, capitalizing on the ram-air effect to achieve nett positive pressure while optimizing airbox size and shape, internal velocity stack lengths and throttle body diameters to sustain it. Much of this is achieved using CFD (computerized fluid dynamics), and gone are the days of thinking that big performance increases can be had by simply throwing on K&N pod filters and open (exhaust) pipes.

I am convinced that a less restrictive aftermarket air filter and matching tune (or piggybacked tune) will see better performance from the R18 - simply because EURO-5 runs the engine as lean as absolutely possible and even trims throttles (and top speeds) back. But we need DimSport® (RapidBike) or DynoJet® (Power Commander 5 / Power Vision 3) to come to the party first. And that will require many more R18's to be sold.

One is obviously welcome to visit your local 'dyno guy', but the chances are good that yours will be the first R18 or even BMW boxer he sees and that the outcome could be dicey, also reliability-wise, apart from providing him with a prepaid training opportunity (-;
It's really ironic. A few decades ago (scary to think the 80s/90s are that old), for better or worse, swapping to a fancy air filter, swapping exhaust, and even changing to better fluids were considered performance upgrades. Then(maybe 2000+?), for both cars and bikes (former much sooner), you had to do real and serious modification to get any real performance gain. I was personally always more about sound and feeling than "faster", which opening things up safely tended to do....

Fast forward to the late 20 teens+ and we are back to emissions standards causing manufacturers to need to hamstring their machinery to comply. Once again, simple mods can give "butt dyno" gains, and even more so now that ECUs aren't static and adapt to air/fuel given to them. I'm personally still a sound/feeling guy, and the only bike I've ever owned that felt less than capable of keeping me safe on the interstate was a Honda CB500. I still do appreciate the ability to once again relatively cheaply improve any vehicle without a bunch of headache.
 
Many years ago I did a Univeristy degree in Mechanical Engineering (BEng Hons graduated 1990) and worked for a while in Engineering then changed jobs and career altogether (long story and maybe a life choice regret of sorts….). Anyway. Having this grounding I subscribe to the belief that unless you really really know what you are doing stock is best. BMW will have access to the very best engineers, computers, modeling software and a huge multi million R&D budget. Everything on that bike will be as it is for a reason. Those little plastic intake tubes for example are there to flow cool air from the front of the bike to the air box, the small diameter will speed the air flow up and that helps low down torque, combustion etc etc. Same for the exhaust, it’s all there for a reason. In years gone by, mid nineties and before things were very different. Motorcycles were pretty crude TBH and whilst not exactly thrown together not a lot better. A ‘guy’ with a dyno could make a difference.

I used to watch a tv programme called Orange County Choppers. Many will know it. They used to make these hideous bikes with ridiculous riding positions, open pipes, no brakes, no suspension. The paintwork and chrome was stunning (credit where credits due) but I cannot imagine any were ever actually ridden. They were an extreme example of DIY bikes, just throwing stuff together that was loud and well…..loud.

Nowadays not only are these engines precision built to very high standards they need all the sensors and hardware intact to work properly. Like a hand in glove. Euro5 emission regs will set the high bar for engineers but that just means they put more effort into everything, not less. The R18 is a masterpiece.
 
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Many years ago I did a Univeristy degree in Mechanical Engineering (BEng Hons graduated 1990) and worked for a while in Engineering then changed jobs and career altogether (long story and maybe a life choice regret of sorts….). Anyway. Having this grounding I subscribe to the belief that unless you really really know what you are doing stock is best. BMW will have access to the very best engineers, computers, modeling software and a huge multi million R&D budget. Everything on that bike will be as it is for a reason. Those little plastic intake tubes for example are there to flow cool air from the front of the bike to the air box, the small diameter will speed the air flow up and that helps low down torque, combustion etc etc. Same for the exhaust, it’s all there for a reason. In years gone by, mid nineties and before things were very different. Motorcycles were pretty crude TBH and whilst not exactly thrown together not a lot better. A ‘guy’ with a dyno could make a difference.

I used to watch a tv programme called Orange County Choppers. Many will know it. They used to make these hideous bikes with ridiculous riding positions, open pipes, no brakes, no suspension. The paintwork and chrome was stunning (credit where credits due) but I cannot imagine any were ever actually ridden. They were an extreme example of DIY bikes, just throwing stuff together that was loud and well…..loud.

Nowadays not only are these engines precision built to very high standards they need all the sensors and hardware intact to work properly. Like a hand in glove. Euro5 emission regs will set the high bar for engineers but that just means they put more effort into everything, not less. The R18 is a masterpiece.
I'd say I 99% agree with this, but this wouldn't be the first time regulations have caused manufacturers to intentionally hamstring their hardware to meet them. Remember the gas crisis and malaise era that followed...

I think history has shown us that manufacturers eventually learn to cope with regulation, but the "beta phase" years seem to tend toward engineering to the regulation first and performance second. Over time, as technology improves and folks learn to make more performance within the regulatory framework, it becomes less of an issue, but out of the gate I think "comply" is the first goal.

Also, I think it is a bit unfair to say that companies, especially ones who specialize in a particular type of product, aren't capable of finding better ways to that an OEM. They also have engineers and testing with untold numbers of years of tuning and refinement. A company that literally makes nothing but air filters and designs them to get the most performance they can, while also not being subject to an accounting department wanting to hit a sticker price has a lot more leeway with a $100 aftermarket solution. That isn't to say such a thing is always better or good/bad, it's just to say that an OEM coping with brand new regulations may be apt to stifle an acceptable level of performance, while the aftermarket has no obligation to do so.
 
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