Reason behind OEM air intake plumbing?

MIG

Road Therapy...
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Drifting between Las Vegas, NV and Tucson, AZ...
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What's the engineering reason behind the way our R3's are piped for the OEM air intake? I've not modified mine yet; but I plan on installing the RAM AIR in the future. I've often wondered this and am thinking maybe it's really a cost-based solution or possibly keeping engine parts below a certain performance threshold for longevity? When I think about it, my HD V-Rod and my wife's Challenger suffer from the same fate.

-MIG
 

1K9

Big Cruisers 4 Me
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May 24, 2016
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Clear Lake / Houston, Texas
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2007 Rocket III
What's the engineering reason behind the way our R3's are piped for the OEM air intake? I've not modified mine yet; but I plan on installing the RAM AIR in the future. I've often wondered this and am thinking maybe it's really a cost-based solution or possibly keeping engine parts below a certain performance threshold for longevity? When I think about it, my HD V-Rod and my wife's Challenger suffer from the same fate.

-MIG

Global warming.
 

Kojack1970

Turbocharged
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May 3, 2018
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South Grafton, MA, 01560
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2016 Rocket Roadster and 2000 HD Fatboy
What's the engineering reason behind the way our R3's are piped for the OEM air intake? I've not modified mine yet; but I plan on installing the RAM AIR in the future. I've often wondered this and am thinking maybe it's really a cost-based solution or possibly keeping engine parts below a certain performance threshold for longevity? When I think about it, my HD V-Rod and my wife's Challenger suffer from the same fate.

-MIG


Blame the EPA

Vehicles have been leaving the factories running in a very lean condition for decades due to EPA requirements for emissions. When I bought my 00 Fatboy, which is a twin cam 88 with a CV carb, that darn thing would fart back out the carb all the time because it ran so lean. The only way to avoid that was to pull out the choke/ enricher knob just a bit. It didn't matter if it was cold or warm, still farted through the carb. I finally got a CV performance kit which replaced the jet, emulsion tube and a few other parts in the carb. Ran perfect after that. For the Rocket, we all know it's significantly detuned and comes very lean from the factory. I think all the extra plumbing is just another method to restrict the engine and lean up the combustion. It's certainly not cost, plastic is cheap!
 

GPMAZ

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Arizona
I think that the noise limits rules play apart. reduce intake noise and you can increase exhaust or mechanical noise

That's right. EPA mandated noise measurements are made at idle and then at a percentage of max RPMs at given distances. If you want to see the difference the intake makes get a sound pressure meter and measure the overall level of the R3 with stock intake and then with aftermarket intake. The difference is what Triumph could allow for in exhaust and overall engine noise. Burying the intake effectively quiets overall sound. With an engine as powerful as the R3, the relatively small loss in power was likely seen as an easy trade off for Triumph.
 

Dr.D

Octane Boost
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That's right. EPA mandated noise measurements are made at idle and then at a percentage of max RPMs at given distances. If you want to see the difference the intake makes get a sound pressure meter and measure the overall level of the R3 with stock intake and then with aftermarket intake. The difference is what Triumph could allow for in exhaust and overall engine noise. Burying the intake effectively quiets overall sound. With an engine as powerful as the R3, the relatively small loss in power was likely seen as an easy trade off for Triumph.
Never thought about that but I have found the noise thing to be true. After I put on the triple K&N filters the intake noise is quite loud. I love the growl of that thing sucking air.:thumbsup:
 
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