I finally got around to testing the contoured air box insert I whittled up a few months ago today.



The handlebar speedo cam videod a solid 1kph gain in trap speed from a standing start. 2 previous runs the other day without the insert netted solid mid 89kph trap speeds and today it was definitely mid 90kph. Not a huge gain but it all adds up and this mod can be used no matter where or how you ride your bike.

Wheelies when banging the 1-2 shift were noticeably stronger-one of them causing me to abort as the front end just wasn't returning to Earth quick enough, and the bike was heading toward the soft shoulder

Now that I know it works I'll probably use the 2 existing emissions hose nipples above and below the air box outlet to drill some short holes into the back of the insert, epoxy in some studs, and once in place add some nuts to make it removable. I have an extra eBay air box so I can do that 'off the bike' and just slip it in when it's done.

Anyway getting rid of the sharp corners at the entry to the air box spigot has seemed to have help. Not a total surprise, but nice that it was enough of a gain to be able to actually measure it.

 

Fantastic !

 

I've pulled it out and will retest it again after I shorten my test section on the hwy to have me crossing the finish in mid rpm range 5th gear rather than tapped out rpm-wise at 8200+ in 5th, so any mods have a better chance of showing their value as the engine will still be accelerating toward 8200+ at the finish.