WOW ! I am amazed this error has not been pointed out before.
My 172S "Information Manual" p/n 172SIM dated 30 May 2000 has, indeed, the same kg to lbs error on the figures you referenced. I've checked my other Info Manuals for the 172R and they're correct, at least back to 1986, and have found no similar errors in my collection of 182 manuals.
Nice catch ! (Yes, I believe the Cessna "pounds" scale is correct as you mention, but they goofed up the kg conversion).
BTW, Cessna singles came with an unofficial "Owner's Manual" until 1976, when they adopted the GAMA formatted "Pilot's Operating Handbook" (POH) - then, in 1979, the FAA Approved "Pilot's Operating Handbook and Airplane Flight Manual" (AFM) became required equipment. The "Information Manual" was introduced then as a duplicate of the AFM, but not approved as a direct replacement for the actual AFM.
I'm going to cross-post this at the Cessna Pilots Association to make sure everyone is aware.
Again, NICE CATCH ! Since it obviously affects an FAA Approved AFM, there really should be an Airworthiness Directive (AD) issued to point out the problem (even though I'm not a fan of excess regulation, W&B issues ARE important.
Cheers.
