I don't have first-hand experience with rim weights for the firecrest line, but the following site has many rim weights listed. Check the drop down menus for rims:

http://www.wheelbuilder.com/store/wheel ... lator.html

Cool, thanks. My calcs were that they were about 500, so that backs it up.

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Snacking on carrot sticks - Where did it all go so wrong?
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Finsbury Park CC

If it's any help I can tell you my 2012 303 FC CC complete wheels as supplied by Zipp are 680gr front, 820gr rear

yeah when you blow out going 30mph down a 12% incline...

latex+carbon clinchers= OUCH!!!!

Myth.

from BikeRadar.com

I don't know if I trust a condom to hold up at 400+ which I would say is conservative for where the bottom of the tube is contacting the rim considering the peak hot spots on either side of it are at 530+...

Maybe in Kansas that setup would be fine...

funny thing about carbon fiber-it's quite the thermal insulator across plies. carbon-carbon car racing brakes (built completely differently) had local hot spot problems until they managed to get fibers aligned across the rotor.
im sure Waldo can chime in here with brake surface/tube temperature differentials?

did a little site search http://weightweenies.starbike.com/forum/viewtopic.php?f=3&t=95233&hilit=zipp+rim+heat&start=15

Waldo says it can be done (In Indiana) but he personally doesn't do it nor does he recommend it.

Besides with all the super duper aero benefits of the Zipps what does 20 grams per tube really do for you anyway? oh yeah this is weight weenies!

This is from Zipp with their new heat sensing cameras to show the brake track temps for their research.

The FC line of wheels are treated on the tracks to reduce the temps and prevent any issues with blowouts/overheating and fading on both clinchers and tubulars.

But still, in any extreme conditions, even the best can fail.

I'm running the Vitt/Mich setup on my rig.
53 mph down a 12% incline...no issues at all, except one hell of a brake pad squeel...and the pads are angled in. (170lbs rider)
Ambient temp was around 60-70 degrees. Might be a different story when it gets to be 100+ in my neck of the woods. (if amb temp matters)

good post. I know someone who is about to buy the 404's and is/was concerned about this. anyone else care to comment on their firecrest exp with latex?

Waldo am I right in guessing the 303CC is a softer ride than the 404CC and only marginally less aero using the same rubber? Eg Ultremo ZX 25 or GP4000S 25?

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Don't let the truth get in the way of a good story......
Argon
CAAD9 6.78Kg
Supersix 6.78Kg

Going fast down a steep descent isn't a problem. It's when you have a lot of tight turns that you have to brake for that's the problem. The frequent braking generates a lot of heat and the low speed means there is less convection to draw it away. Going 20 mph is the worst for brake heat; see _Bicycle Science_ 3rd. ed.

Ambient temp does matter. If you start out at 100 instead of 60 degrees f then you're 40 degrees closer to the epoxy's transition temp (where it starts getting soft) before adding brake heat.

For the record, I got 1600 miles out of my Vittoria's before they started showing through on the rear. I was using the 23's b/c I heard they ran large and more like 25's. I just switched to a set of Ultremo ZX 25's when I ran into the mounting issues with the Mich latex tubes.
Gotta slowly inflate! Amazing the difference between 23s and 25s.
I was able to slap the 23's together without issue and did the same with the 25s and lost two tubes in the process. Two explosions later while inflating really makes a guy gun-shy on the 3rd and 4th!
I only got one puncture during the 1600 miles on the Vitt/mich combo.
I always have a backup set of tires on hand, so this time around I have the Vitt 25's sitting on the shelf to replace the Ultremo's if need be.
The Ultremo's seem really responsive compared to the Vitts. Very noticeable difference.
Speed wise, I havent given them the downhill speed test yet.

as far as tube weight, that's not the reason to go latex, as the lightest butyl are the same weight (or lighter) as latex ones. it's about rolling resistance (but i have a feeling the lightest, thinnest butyl reduce the rolling resistance gap considerably)