Lot's of good info in that video. Unfortunately, some misleading and incorrect info, too. Which is a shame.
The jet size change was necessary not because of the stacks letting more air, but rather the change in runner length raised the pressure in the carb throat closer to atmospheric.
There was no volumetric change to the engine mechanicals.
Therefore, it does NOT get more air with the stacks (particularly at less than red line RPMs). They just restored the fuel flow with bigger jets for the lower air pressure differential they induced with the filter to stack change.
- They totally ignored the slide needle position on the slides and the midrange throttle valve mixture settings.
- High marks for video production values, below average marks for technical merit.
The "gratifying" ride showed disregard for actual air fuel ratios at various throttle positions. And the need to be the primary focus of a circle jerk.
It ain't science. It's just entertainment, with a little "education" thrown in.
Very cool engraving on the bike, though.
Cheers,
