This BB came out of 1981 Lotus Odyssey I picked up off a scrap pile. There appears to be a center weight held to spindle with 2 set screws, and I was wondering what the idea is behind it? I didn't move it because I thought it was aligned to allow the longer drive side. Are the needle bearings replaceable or shouldn't I bother? I cleaned, re-greased, re-installed, cranks back on, and they spin pretty smoothly. Also, since there's no lock ring involved is there a special procedure for installing it properly? Any feedback appreciated!

Bike came with all original parts per catalog reference I found. It was in pretty bad shape with lots of rust, but, it's cleaning up nicely overall except the drive side chrome stays are pitted, so, I'm going to leave as is and maybe only touch up the scratches and dings dings. Tange Champion 1.

I would think its main job is as a spacer for the inner bearings, don't think its a weight since its the same all the way around.

Wow, that's really cool and I've never seen one before. It sure does look like the center piece is there to make the chainline adjustable.

So, I guess the needle bearings run directly on the spindle, and then the ball bearings run against the center piece? Pretty neat stuff, and I would think extremely durable, too.

Why did this never catch on?

Headset looks like a Swiss-made EDCO, so maybe the BB is, too. I installed one years ago but that was an eccentric to be installed in an Italian-threaded shell and was different from this one.

Maybe Bullseye brand.

https://www.bikepro.com/products/bott...ts/bulls.shtml

Thanks guys! The Bullseye reference describes it perfectly as "floating", and I that's what I first thought as I was reinstalling. The inside chainring touched the stay as I turned the crank and I simply adjusted both cups to move it out a few mm. I would guess that feature can be helpful when tuning the drivetrain.