[FUNFER2]

Not even close to worried, I measured no deflection with 500lbs. My neighbor is a engineer and said no issue. He's the one that gave me the 2" solid bar and the 6' length across the 2x10 @16" centers rafters is fine. Being in the midwest with heavy snowfall amounts, our house is built very strong.

I don't think 100lbs of my Tremec, billet aluminum flywheel, clutch and bell would make any difference, but I'll ask Gary.
Can't be too safe !