Looking for any comments or input on which rear disc to buy: Zipp 909, Hed Superlight or Renn? …any others worth considering?
Thanks
"…any others worth considering? "
If you want a “real” disc the Renn is the best value. If performance is your only issue, a disc is a disc is a disc, so then there is no reason to spend any more than for this:
http://www.excelsports.com/new.asp?page=8&description=Wheel+Cover&vendorCode=CHAERO&major=1&minor=24
I knew the first response was going to be from cerveloguy with the CH Aero cover. I used a cover for 10 years, and I hated every minute of it. Yes I was faster, but it was really heavy (1600g) and such a pain to do simple things like pump up the tire, true the rim, etc. that I eventually dumped it and bought a Renn. For value, I think the Renn can’t be beat. That being said, you can pretty much climb mountains with the Zipp without a significant weight penalty…I just couldn’t justify the cost. I am not thrilled with Hed’s bearings so far, having roughly 2x the drag of my Velocity Spartacus. Hopefully for the additional drag the seals at least will keep all the dirt out for a looooong time.
“I knew the first response was going to be from cerveloguy with the CH Aero cover.”
Hmmm, I’m really that predictable huh??? Someday I’ll upgrade to a Renn, but for thirty bucks secondhand off ebay I did pretty good!
CAMPAGNOLO GHIBLI!!! If you have $2,500 to blow!
Renn. Hands down.
and it makes that cool whumping noise.
That noise is the icing on the cake. It’s soooo cool to be making such a racket as you blow past people 
That noise is the icing on the cake. It’s soooo cool to be making such a racket as you blow past people
I’m using a Hed disc and Yes it is cool to crack thunder while your torquing up a hill. I think it actually plays a mind game in the people around you. They know your barrelling down on them. hehehe…