Thanks! I designed that lug, with a lot of input from Bill Davidson of course. I made the steel masters that we set to Takahashi to have them reproduce by investment casting.

It's the seat lug from the "oversized" set originally designed for the Stiletto frame. Stiletto also got a slightly OS DT (30 mm), and the seat tube (which is normal at the top) flared to oversize and ovalized at the BB shell. After we got the OS lugs, we started using the two TT lugs on the larger frame sizes of Impulse. Impulse never used the OS DT, ST or chainstays though -- it stayed with trad diameters everywhere else, OS (9/8") only for the TT and only on big frames.

If you ever see a Stiletto, don't blame me for the BB shell -- they LOST the master I made, that took like 40 hours to make. Bill told them to just "wing it", as in do as they saw fit. It came out a little clunky-looking IMHO and with some errors that we had to fix on each and every shell -- more work overall than just making a new master would have been.

Other than that one time though, Takahashi was very good to us. The BB shell on the Impulse, no OS all trad tube diameters, is one of the nicest BB shells ever made. Look on the bottom of the shell to see a little raised hallmark cast-in, it means Hitachi, who did the actual casting.

-Mark Bulgier, Seattle