Originally Posted by Poguemahone
I believe Tange numbered their steels, with "1" being the highest grade and "5" being the lowest I've seen. The Tange "1"s and "2"s are very nice high quality db tubing, comparable to Reynolds.
Whatever this is its one *****in' ride. Kept up pretty decently with a coworker on his '04 Bianchi San Lorenzo (10spd Dura Ace) yesterday on a 30mi warmup
As far as the grade of Tange, I'm not sure what this is. I think the OS3 may refer to the quality of the tubeset in this case, as the sticker just says Tange Chromoly with no grade indication. This was definately intended as a race bike in its day, zero eyelets and a sweet chain-hanger... internal cable routing too (can't wait to change the cables out
)