ORIGINAL: flyinwalenda
I don't think it was BUT I never had one let loose however I never propped them to run over 8K. There is a Ryobi 30cc out there too that would be a conversion engine that is a bit beefier than the 31cc and can push higher rpms after conversion......closer to 10K. I never had a Ryobi 30cc so I can't say for sure.
I have seen a lot of newer Ryobi yard machines lately with 30cc Homelite engines instead of the original Ryobi design. I believe this is probably the engine you are referring to, because the Homelite engines will indeed turn 10,000 rpms without hurting themselves if everything is set up properly.
AV8TOR