R18 Louvered Performance Plates

[Gr8adv]

Good idea and I applaud the thoughts, but... I expect air temperature not air volume is the next level up from the dna stage 2

Having gone from the snorkels to the open dna mod, we add what I would consider unlimited airflow to the airbox (As compared to the snorkels). Less velocity, but more available volume. I cannot imagine that the post dna system is starving for any air quantity.

Now air temperature that’s another matter. If the side vents can provide cooler air, I would expect the possibility of a material difference in performance. However I question that as a possibility given 1) they are on the side and away from direct airflow, 2) the ‘new’ air travels across the cylinder heads.

Now, venting through the breastplate (if possible) or providing forward facing scoops/snorkles/vents from the side plates would be of interest.

You get what you pay for with my opinion.

This comes close.

 

[Lennstang]

I hear you. The R18 airbox design is very limited by the space available. BMW wanted to keep the bike retro looking and appearance came at the cost of HP. The stock factory snorkel system moves the air inlet as close to the front of the bike's 6 front louvered opening in order to grab cooler air. Once you remove them and go the the new air filter setup, you now don't have the stock restricted cold air intake system. Once the engine reaches its heat soaked point, the air inside the aluminum cases is heating the intake air. Allowing the air to constantly vent through the cases will bring down the air intake temps and increase performance. My louvers are CAD designed to pull air from the engine cases. We tested 4 designs before settling on what you see in the pics. Once the bike is in motion, the air flow is quite good, even with the ports being somewhat blocked by hoses and wires. This is the simplest solution to increase airflow without hacking up the cases with holes. I'm not expecting a huge improvement but there should be some. They also add a custom look to the bike.

 

[bdalameda]

I was thinking it would be fun to make a set of intake stacks that were similar looking to a P51 Mustang exhaust stacks. You could have them facing forward. It also may work with the stacks facing rearward. With the interior snorkels removed the air would free flow through the chamber and the stacks facing rearward may create a draft to pull air through the front louvers and exit the stacks. I think these would look pretty cool.

 

[LBV]

I expect air temperature not air volume is the next level up from the dna stage 2

Thinking further along these lines ... you know maybe this product may in fact help as opposed to hinder based on my initial thoughts and here's why.

Having the airflow across these plates and pulling the air out of the intake area would normally be a bad idea if it was a closed system but it's not. The intake area for fresh air is at the front so what this "sucking-air-out-from-the-sides" effect may end up doing is in fact suck MORE FRESH air in from the front so temps stay as close to ambient as possible.

To test, you'd have to put a temp sensor near the air filter and run with both the stock plates and these open-type ones and compare the temps (under same conditions of course) but I can see a possible plus now.

 

[skidward]

I think it should be a scoop design similar to a hood scoop on a car.

 

[LBV]

Agree there ^

 

[Gr8adv]

I’m not going to rain on fun ideas; I will weigh in. Pulling a vacuum to recycle air is technically valid. Even if it works to some degree the system however will never be as productive as pushing air in.

I expect that if this Naca Duct fits, the amount of cool air entering will be dramatic at speed. I may get a couple to see just for fun.

 

[Petrus]

Yes, Petrus is taking a different approach by trying to Ram the air back into the airbox.

'Ram air'???
I suggest you read what I wrote.

 

[Noelpolar]

All I can say is.... my bike has the DNA 2 filter mod (so no top filter box or snorkels), free flowing exhaust with stock headers and BT moto (ie. BREN) tune and:

1. I removed the engine plates and rode the bike and did not feel a difference; and
2. I removed the tune, left the plates on, rode 200km and felt a significant loss in bike performance... (I did not notice such a gain when I initially added the tune....go figure)

Anyway, the little boy in me might still want to tinker with the plates... I get a bit more little boyish as each year passes these days (wife verified).

 

[Petrus]

My feeling is that air intake only really changes if you've changed over the air filter and removed the two black plastic snorkels.

Exactly.

I like the idea of the honeycombed or louvered vented plates - very cool; and 2. it makes engineering sense, particularly if the rest of the restrictive intake hardware is out of the way.

Thank you.


On the gains I will be short as I only tried it solo for a few weeks: I 'engineered' it because I háte a throttled engine and because I wanted all the smoothness/oompf for the sidecar driving.
Ok, the result. I used the two accelerometer apps I used for my car performance projects. The max increase is 10% at 2 - 3,5k whereas at top it tails off to 5.
As observed in the original threads, the response is much more direct. Also it revs notably quicker, more freely. With the sidecar it definitely takes getting used to because the body antics can easily see you unintentionaly free some horses.
I dubbed it 'hard rock' mode as a pun but it covers it: I have the engine in 'roll' which is now 'rock'.

Bottom line:
- makes sense
- effective
- dirt cheap
- autotunes within OEM parameters
- looks

Lastly I want to comment that I lóve the 'unsophisticated' old skool tuning costing beer money. I have no doubt whatsoever that a repro changing the OEM parameters is 21st c. but then that also costs 21st c. money.

 

[KAus]

All I can say is.... my bike has the DNA 2 filter mod (so no top filter box or snorkels), free flowing exhaust with stock headers and BT moto (ie. BREN) tune and:

1. I removed the engine plates and rode the bike and did not feel a difference; and
2. I removed the tune, left the plates on, rode 200km and felt a significant loss in bike performance... (I did not notice such a gain when I initially added the tune....go figure)

Anyway, the little boy in me might still want to tinker with the plates... I get a bit more little boyish as each year passes these days (wife verified).

Yep, what he said. I'm not convinced the plates themselves are a limiting factor, but freeing up the airflow through the plates can't hurt (and its small, simple, and pretty cool in visual and fabrication terms). But I'm also interested - anyone else taken them off completely for a spell?

 

[Petrus]

Yep, what he said. I'm not convinced the plates are a limiting factor,

in stock form the harmonicas are
with those removed then the lid on the filter box becomes the limiting factor
with that removed it shifts to the filter element and with that upgraded
thén opening the sides up will add extra air.

It has to be observed though that the filter housing has ludicrously little volume. So whatever we do before has the limit set by the box.

Also BEAR IN MIND and THEN SOME that this is a naturally aspirated engine with two large cylinders gulping for air.This is important to realize because the only 'feed' is atmospheric air pressure. Any restriction = pressure drop = less BMEP -> less powah. It's elementary had Conan Doyle say Holmes.

 

[HUNTS]

So basically, unless I remove or open up those snorkels (which I can’t do for another 4 years whilst the bike is under warranty), I can ‘Honeycomb’ or ‘Machine Louvre’ the name plates all I want and it’s going to do nothing. I obviously can’t do a tune either unless I want to remove it every 2 months!
Over to you….

 

[Petrus]

So basically, unless I remove or open up those snorkels (which I can’t do for another 4 years whilst the bike is under warranty), I can ‘Honeycomb’ or ‘Machine Louvre’ the name plates all I want and it’s going to do nothing. I obviously can’t do a tune either unless I want to remove it every 2 months!
Over to you….

Affirmative.

No use beefing of the links in a chain and leaving the weakest ones.

 

[Star-Lord]

What if you did the following:

1. Keep the two accordion snorkels in place; so as to provide a direct path of cooler air into the air box, providing isolation from trapped heated air within the covered space.

2. Create positive pressure within the space where the air box lives, where the two badge plates are of two different designs; one side has forward facing large scoop type holes, and the opposite side has smaller backwards facing holes or exhaust ports. This will essentially vent or remove any hot air from building up within that space, radiated off of the engine; cooling the confined space.

3. Drill a larger diameter hole in the cover of the air box cover; providing additional and cooler air.

I liked the idea of standing off the badge plates; however, I thought of using some sort of filter material sandwiched between the engine cover and the badge plate, just to help keep debri and such out of that space.

I'm still using standard paper filters, with the stock accordion snorkels in place.. but love reading this thread and the different beer money upgrade ideas..

 

[LBV]

I thought of using some sort of filter material sandwiched between the engine cover and the badge plate, just to help keep debri and such out of that space.

I thought the same too ... some old flat K&N air filter (cleaned & re-oiled) or similar cut to size would work I'd think.

 

[Petrus]

however, I thought of using some sort of filter material sandwiched between the engine cover and the badge plate, just to help keep debri and such out of that space.

There is an 'unfiltered opening at the top for the engine mount and cables.
This opening is also the reason why the BMW engineers added holes in the filter box lid.
As I observed, when I removed the snorkels they were dusty on the outside so air doés flow through from the top, through the holes in the lid.

 

[Noelpolar]

So basically, unless I remove or open up those snorkels (which I can’t do for another 4 years whilst the bike is under warranty), I can ‘Honeycomb’ or ‘Machine Louvre’ the name plates all I want and it’s going to do nothing. I obviously can’t do a tune either unless I want to remove it every 2 months!
Over to you….

my bike has another year and a bit of warranty and I did my stuff over a year ago. I've removed the tune only once for the reverse fix (which I knew required a bike "flash").

When taking my bike in once a year for the service I tell them no filter required (I had just replaced it) and also tell them not to do any software updates.

I probably will still remove the tune.... then I get to experience how much better the tune is and I feel all warm inside when I reload it later (A bit like eating only salad for a day).

If really worried about the filter etc being seen and noted by them.... it would take 15minutes to put back before taking the bike in.... 45 minutes with a beer and crisps..... or all day if you want to just hide from the wife in your man cave.

Keep in mind the air in Australia is twice as dense as the places above us... and for the most part it spins the other way.... and holes in these plates will allow the bike to fill with spiders and snakes just inches away from your crutch.

 

[Noelpolar]

I was thinking it would be fun to make a set of intake stacks that were similar looking to a P51 Mustang exhaust stacks. You could have them facing forward. It also may work with the stacks facing rearward. With the interior snorkels removed the air would free flow through the chamber and the stacks facing rearward may create a draft to pull air through the front louvers and exit the stacks. I think these would look pretty cool.

Someone allready done this, several years ago.... saw it on Facebook but can't find it now.

 

[DIAGREG]

The label "performance plates" being attached to any aftermarket plate made for this area, I keep wondering if they are in fact making any difference? What I'm getting at, is if the stock covers are a real issue, a vacuum gauge attached to a stock plate would show that there is indeed any restriction, and also whether or not it is corrected by adding a "performance plate"

If and when the dyno testing is done, add that test to the list, if there is a measurable difference, I'll buy a set. (may buy anyway, they at least look cool!)

Greg