IAT & Flappers

[JamieMac]

Guys,

Just doing the big service on the 2020 Gen 4 and was amazed at the IAT positioning combined with the flapper valves in the inlet. I had a nightmare this year in the Mountains when the temperatures got high or on our hot days. The bike was so, so fluffy below 6000rpm. My mate was on a 2022 S1000R and we were on average reading 20C difference between the 2 bikes over the trip. So they've obviously moved the IAT on the 2022 'R'

Now I know why! BMW block off 90% of the inlet below 6000RPM when the flappers open. All in the name of reducing engine noise! See Pic!

They'll be going in the bin and I'll move the IAT behind the Dash.

J

 

[pauly]

One of the best things about my then new K6 GSX-R1000, was the intake noise. And the exhaust noise when I fitted an Akra can.

 

[Sam76]

Did removing the flappers bring any fault codes up?

 

[pauly]

Now I know why! BMW block off 90% of the inlet below 6000RPM when the flappers open. All in the name of reducing engine noise! See Pic!



View attachment 6550

Variable intake opening, to maintain air speed at lower revs too.