The CB1100 Community Forum

Just messaged with Tetsuya Kudo a moment ago- and he confirmed this part was changed on the 2017 for noise regulations.

The best article I have ever read about the motorcycle airbox is from California Scientific, super interesting and if you want to go full Engineer mode its all there. This is why I leave all my bikes pretty stock and why I am happy that a Honda filter and airbox will be just fine for me.

https://motorcycleinfo.calsci.com/Airboxes.html

Bookmark added. Great explanation.

They didn’t say Helmholtz resonator. I like saying Helmholtz resonator. Not an engineer though

A message just came in to the forum inbox. It said:

Quoteear Admin and Moderators,

Could you please ask Lord Popgun to stop using my name just for the heck of it? It's messing with the data I'm trying to collect from the inter webs on the number of times my name is mentioned in serious works.

Yours etc

Helmholtz Resonator

(02-18-2021, 10:55 AM)Cormanus_imp Wrote: [ -> ]A message just came in to the forum inbox. It said:

Quoteear Admin and Moderators,

Could you please ask Lord Popgun to stop using my name just for the heck of it? It's messing with the data I'm trying to collect from the inter webs on the number of times my name is mentioned in serious works.

Yours etc

Helmholtz Resonator

Ha, ah, ... Popgun, say it again? Peez!

This is a very serious issue.
Lord Popgun needs a lawyer.

(02-18-2021, 10:55 AM)Cormanus_imp Wrote: [ -> ]A message just came in to the forum inbox. It said:

Quoteear Admin and Moderators,

Could you please ask Lord Popgun to stop using my name just for the heck of it? It's messing with the data I'm trying to collect from the inter webs on the number of times my name is mentioned in serious works.

Yours etc

Helmholtz Resonator

that cal sci article sounds convincing, but fails to explain how, when I removed that little round plug thing from the airbox, the front end came off the ground when I gassed it...

Its the HELMHOLTZ RESONATOR thing

(02-18-2021, 09:41 AM)Tev62_imp Wrote: [ -> ]The best article I have ever read about the motorcycle airbox is from California Scientific, super interesting and if you want to go full Engineer mode its all there. This is why I leave all my bikes pretty stock and why I am happy that a Honda filter and airbox will be just fine for me.

https://motorcycleinfo.calsci.com/Airboxes.html

Thanks for the link to the article, it reminds me of the Toyota famous "T-VIS" (Toyota Variable Intake System).
What the T-VIS does is varying the air intake runner length in order to get more torque at certain rpm. It uses a butterfly plate to close one set of intake runner and opens them when more torque is required at certain rpm (air resonance).
By the way, this system was designed by Yamaha (their musical department).
Regards
Alain