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The airbox is a resonant chamber and is designed to "pulse". The disturbed effect mentioned by GoldOxide is a reflection of a poor design affecting that natural pulse. This is the very reason why most snorkel deletes or pod filter for airbox replacements fail to produce the results a rider expected. It is also why this stuff is a complete waste of money. There is no end of suckers buying the airbox inlet replacement plate for Royal Enfield 650's, it does absolutely nothing but they will all tell you it works by "freeing up" the airflow, hilarious. You have to fully appreciate what you are doing in this circumstance, I believe PowerDubs has a good handle on this
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I have posted a link to this before but for those that have not seen it it is a super article on resonant airbox design.
https://motorcycleinfo.calsci.com/Airboxes.html
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(10-01-2021, 12:54 AM)Tev62_imp Wrote: The airbox is a resonant chamber and is designed to "pulse". The disturbed effect mentioned by GoldOxide is a reflection of a poor design affecting that natural pulse. This is the very reason why most snorkel deletes or pod filter for airbox replacements fail to produce the results a rider expected. It is also why this stuff is a complete waste of money. There is no end of suckers buying the airbox inlet replacement plate for Royal Enfield 650's, it does absolutely nothing but they will all tell you it works by "freeing up" the airflow, hilarious. You have to fully appreciate what you are doing in this circumstance, I believe PowerDubs has a good handle on this .
I have posted a link to this before but for those that have not seen it it is a super article on resonant airbox design.
https://motorcycleinfo.calsci.com/Airboxes.html
I haven't seen this link before, thanks for reposting, it's very informative in a "that makes perfect sense" way. I never played with the airbox, though I was tempted with my Tiger 1050, as I've seen mutliple owners drill extra holes and even remove the cover. Then I decided it had all the pull I'll ever need, and I left it alone. So now I understand that modifying the airbox for better resonance is actually complicated math (I suck at math so it's always complicated) and I wouldn't dare get into it
'14 CB1100 STD 5 speed
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Not much to be gained on the CB1100 intake.
http://cb1100forum.com/forum/showthread....#pid187441
On my 2012 Triumph Bonneville it was a noticeable improvement to remove the snorkel.
The design on my 2022 Triumph Bonneville Street Twin does not seem to lend itself to any practical improvements. I did cut off the interior part of the snorkel to better distribute particles to the air filter. As the original filter was accumulating grime unevenly (4800 miles in 4 months)
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My '04 Kawi Nomad 1500 had an air inlet like the Mekong delta, full of turns, changes in direction, goes between the V cylinders to get the air good and hot, idle air injectors, and it pinged like a xylophone playing boogie-woogie. I totally opened the intake, blocked off the old intake, removed the air injectors, put an air cleaner on the right side and cobbled a mount with an intake, and put a Power Commander on it and opened the exhaust some. It made a huge difference. Throttle response greatly improved, it sounded better and ran like a scalded cat. The pic shows the air cleaner I repurposed.
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I am sure it did perform better, as the FI on these bikes was just added to an already existing engine that used to have a carburetor. There wasn't much engineering involved it seems. Victory was one of the first manufacturers to start actually designing big twins with FI, and on these you can actually find a snorkel inlet under the tank and an actual airbox. The thing about Vulcans and some similar bikes is that they still use the same old engine design
'14 CB1100 STD 5 speed
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I tossed all this "take the snorkle off and open my air box" stuff (when I had the Griso) when I looked at the intake snorkle on my F150 with twin turbo's. Intake was not much bigger than my Griso's. Truck performed just fine so I paid more attention to real important things - like finding a comfortable seat.
