Originally Posted by Boss Moniker

That includes a pretty beefy tire, solid axle, and surly fixxer w/cog. And it's really only like 4.3lbs. With a freehub, no tire and no cassette, and a hollow axle it's 2.8lbs according to Hed's site.

It is a lot of weight, but the aerodynamic advantage is greater than the weight penalty.. that is, once you're up to speed. Accelerating is definitely harder. Remember that 90% of total resistance you encounter in normal conditions on a bike is due to wind drag. The other 10% is due to things like drivetrain efficiency and overcoming the bike's inertia. So you add a little bit of inertia, but cut the resistance by a significant amount. So it helps on the track and if you're doing time trials, but otherwise it probably sucks.

And I was really surprised at my bike's weight even with the rear.. it was about 18lbs with disc, and 13.7 without. And this is a steel frame too! So if I were to get a lightweight rear, I could probably get it down to 15.9 or so.

And you guys are probably right about the filler. I'm just nervous about sanding the carbon fiber's surface so the filler coat would need to be a little thick, which I assumed would add weight. But it probably depends on the material. I'll look into it, but I probably couldn't paint it until it warms up in the spring