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R18 Louvered Performance Plates

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Anecdotal. I opened my side plates up with the DNA install. It made sense by observation but I did not do any analysis. So today I went for a rip (more on that in the next paragraph). Stopped on the freeway and the portion of the side plate that is exposed to the ‘hole’ was warm. The rest with the carbon backing was pretty hot. Stopped at a traffic light and the entire side plate was untouchably hot. Possible cause?: Cool air moving through the opening? Or simply cool ambient air against a plate not heated by the solid case. Idk

The rip… I have ridden dirt bikes, baggers, dual sports, enduros and a r1000r for a year or so. With the mods done on my OG R18 there is nowhere I feel comfortable opening it up to full throttle. Not sure cams are necessary.

Mods: cat removal: flapper removal: Fishtale baffle drilled, DNA stage 2: Brentune.
 
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Anecdotal. I opened my side plates up with the DNA install. It made sense by observation but I did not do any analysis. So today I went for a rip (more on that in the next paragraph). Stopped on the freeway and the portion of the side plate that is exposed to the ‘hole’ was warm. The rest with the carbon backing was pretty hot. Stopped at a traffic light and the entire side plate was untouchably hot. Conclusion: Cool air does move through the opening.

The rip… I have ridden dirt bikes, baggers, dual sports, enduros and a r1000r for a year or so. With the mods done on my OG R18 there is nowhere I feel comfortable opening it up to full throttle. Not sure cams are necessary.

Mods: cat removal: flapper removal: Fishtale baffle drilled, DNA stage 2: Brentune.
I am not sure I understand what you are concluding?
 
I am not sure I understand what you are concluding?
Well not sure conclusion is really the best word I could have chosen, I’ll change that.

But definitely with the bike moving, the portion of the side plate that is ‘open’ is far cooler as compared to not moving. I’ll let smarter people of me draw their own set of possible conclusions. Thx
 
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Great points and I agree, this is a low rpm engine designed for torque, not HP. Harleys have notoriously restrictive cylinder heads. The 117 is much better than in the past. But cams and better heads move the power into the upper RPM ranges. So you do give some here to gain elsewhere.
The R18 already has a great 4 valve cylinder head. Because of the Euro-5 emissions, the cams are very conservative and don't have much overlap. This is an area of opportunity. Cams and the proper tune would really wake up this engine. Until then, we can only do so much. Performance plates are just another way of helping. By allowing more air for combustion. Open up the exhaust a bit and the engine will breathe better. The torque of the R18 is what gives this bike it's personality.
Some nice catless headers should be your 1st focus..... to sell to your new mates here..... lots with fishtail'itis here would bite.
 
Since I really like my new engine plates a LOT more than the original ones; I’m giving the originals to a mate to drill holes in the middle section (about 2cm in from each end), put them on and see if I experience Nirvana… if not, no loss.
I already have the sports air filter, but can’t do the snorkel thing due to warranty, although I REALLY want to. Since I don’t have the knowledge how to anyway, my mechanic would charge me. He is a qualified BMW Mechanic (ex Motoraad) and could clear codes, but then I would have to pay for ‘snorkel reassemble’ plus the code clearing.
Anyway, I’ll see how it goes.
 
Since I really like my new engine plates a LOT more than the original ones; I’m giving the originals to a mate to drill holes in the middle section (about 2cm in from each end), put them on and see if I experience Nirvana… if not, no loss.
I already have the sports air filter, but can’t do the snorkel thing due to warranty, although I REALLY want to. Since I don’t have the knowledge how to anyway, my mechanic would charge me. He is a qualified BMW Mechanic (ex Motoraad) and could clear codes, but then I would have to pay for ‘snorkel reassemble’ plus the code clearing.
Anyway, I’ll see how it goes.
Air filter Change video.. it's pretty simple if you want to remove the two corrugated air intake "snorkels"; you can always, re-install them if you schedule your bike for service and are concerned about the warranty..

 
Air filter Change video.. it's pretty simple if you want to remove the two corrugated air intake "snorkels"; you can always, re-install them if you schedule your bike for service and are concerned about the warranty..

Thanks… a LOT.
I am going to do this. Does this affect sound, increase Hp and/or torque or simply make the bike run smoother?
I’m sure the answer is all over this forum, but you are Lord, so therefore you have all answers to R18 inquiries.
 
Thanks… a LOT.
I am going to do this. Does this affect sound, increase Hp and/or torque or simply make the bike run smoother?
I’m sure the answer is all over this forum, but you are Lord, so therefore you have all answers to R18 inquiries.
You will notice an increase in engine sound when stopped ... I wear Loop ear plugs so it's not that noticeable for me but if you don't I think you'll hear more "clatter".
 
Thanks… a LOT.
I am going to do this. Does this affect sound, increase Hp and/or torque or simply make the bike run smoother?
I’m sure the answer is all over this forum, but you are Lord, so therefore you have all answers to R18 inquiries.
LOL..!! I have no idea... I still use the stock paper air filter and still have the corrugated air duct pieces in place.

I've been watching this thread closely and trying to determine the preferred setup for my bike.. I get the concept of more air, and cool air; however, I'm not so keen on the idea of lots of hot air within the engine covered space.

The corrugated ducts potentially duct cooler air, in comparison to radiated air within the engine covered space; however, I like the idea of the open badge covers allowing that heated air to vent the space, essentially cooling that space..
 
I get the concept of more air, and cool air; however, I'm not so keen on the idea of lots of hot air within the engine covered space.
I first went with the BT-Moto tune on stock air filter ... honestly noticed no difference in performance.

When I put the DNA stage 2 air filter in is when I felt a difference so I understand your reticence but honestly, once moving, I'd bet hot air is no longer an issue as it's getting sucked in from the front and, for those that have these 'performance plates', the sides just vent even more fresh air through.
 
The corrugated ducts potentially duct cooler air, in comparison to radiated air within the engine covered space;

Actually they don´t. At least not pushed in. Behind the fork / front wheel and mudguard is a lower pressure area with turbulence to boot.
On the move no hot air will be sucked through the side openings.
Yes @Gr8adv I had noticed the covers staying cooler too.

Speaking of cool I am amázed at how cool the engine runs. Even coming up the steep inland mountain roads with the sidecar; i.e. with more load and a bit lower speeds than solo, it rarely gets so hot that the valve cover covers get too hot to touch.
 
Question from the audience… Wouldn’t it be detrimental for someone to fit the underbody guards available online, as these would cause heat retention?
 
Question from the audience… Wouldn’t it be detrimental for someone to fit the underbody guards available online, as these would cause heat retention?

there is no doubt that a sump guard would see less cooling air flowing. 'Detrimental' though implores negative effects and I as the engine runs quite cool I cannot see thát extend.
It has a plastic sump which does not radiate as much as aluminium and has the oil cooler.
So yes, a wee bit less cooling air but no increase in oil temp I think.
Ergo only when you think you may ground the sump but not a cooling problem.
 
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Fwiw.... when doing weird projects.... I walk the isles of shops looking for repurposing ideas...... so.... not quite there.... but not far off..... probably a couple of the generic plates worked into a couple of carbon fibre thingies.....

s-l400.jpg
 
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Fwiw.... when doing weird projects.... I walk the isles of shops looking for repurposing ideas...... so.... not quite there.... but not far off.....

View attachment 21706

on the R18 it would be fixing a non problem, introducing turbulence, instability and less flow to the oil cooler.
 
there is no doubt that a sump guard would see less cooling air flowing. 'Detrimental' though implores negative effects and I as the engine runs quite cool I cannot see thát extend.
It has a plastic sump which does not radiate as much as aluminium and has the oil cooler.
So yes, a wee bit less cooling air but no increase in oil temp I think.
Ergo only when you think you may ground the sump but not a cooling problem.
But these guards are made of metal and cover most of the bottom section where the engine is?
If they are running so cool, why do the engine plates need to be perforated?
I have very limited mechanical knowledge when it comes to the boxer engines.
 
Question from the audience… Wouldn’t it be detrimental for someone to fit the underbody guards available online, as these would cause heat retention?
Why? The sump is super strong..... an idiot could even slide their bike on it.... then get 3 men to drag it back onto it's front wheel. I did this so you wouldn't have to.....

f585f7a9-8c95-40fe-b359-9c47f57dc044-1_all_19445.jpg
 
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