20/24/28 holes in zipp 303 and related questions

For spokes, I'm using 20 rear and 16 front, and I weigh 86kg. If you want a training wheel to be as fast as possible, than 28 rear is slightly less aerodynamic than it could be. 303 will be slightly slower than 404 on descents, but will be slightly (very slightly) faster on climbs.
DT hubs are well regarded.
You should get bladed or oval spokes.
I can't comment on Zipp failures, other than to say that the silent majority with no failures won't post to let you know how they are going, unlike the few with failures.
Indeed, your carbon/tubular wheels should be pretty light (for climbing), but tubular tyres create (very) slightly higher rolling resistance than the best clinchers with latex tubes, and tubulars sound like too much work for lazy me. Their fans are certainly vocal.

hmronnow said:

My LBS (in switzerland) offered a decent deal on a 28h PowerTapSL24 hub with Zipp 303 tubular rim. Front he suggests DT240s hub also with zipp 303 tubular rim. I weigh 64kg (141lbs), and would use it for training, both flat and in the mountains.

- How many spokes should I chose for resp. rear and front?

28 front, 24 rear, laced 2 cross.

(the lbs has a 28h PT2.4 on stock, but is 28 holes excessive for my weight?

4 spokes weigh about 25 grams but even tho light-28 is not 'excessive' for you.

- The weight difference of 4 or 8 spokes is marginal, is there an aero-difference?

hardly noticable-

- Given that almost every ride includes 200-1000 vertical meters of climbing, am I correct to chose 303 over 404 for both front and rear?

yes.

- Is the DT240s good choice for front hub?

Great hub.

- For spokes should I get Sapim CX Ray, DT aerolites or something else?

Pretty thin spokes, why you need 28 in the rear.

- There are some posts about frequent failure of zipp wheels, are there also opinions that it can be a durable wheel?

Depends on the builder, but tubular is a good choice.

- These would be my first carbon and first tubular wheels. I consider both for the lightness on climbs. Is this correct thinking?

yes-

- Any alternatives I should consider?

Maybe Edge rims, not sure they are available on that side of the Atlantic

Thanks
Henrik

yer welcome

Peter@vecchios said:

yer welcome

- How many spokes should I chose for resp. rear and front?

28 front, 24 rear, laced 2 cross.

(the lbs has a 28h PT2.4 on stock, but is 28 holes excessive for my weight?

Didn't you mean 28 rear 2 cross, 24 front radial?

I personally love the feel of my tubular tires, but would never consider training on them on a regular basis. Its too much of a hassle to change, and too expensive to replace for me to ride them daily. I would suggest using them for racing and high paced group rides only, but thats just me.

If I loved the feel of tubulars, I'd ride them all the time, as riding is only for fun for me. Maybe I should make sure that I never try them...

Thanks all for your helpful comments.

I went with 28 rear 2 cross, and 20 front radial, all DT aerolite spokes.
(being in switzerland, DT aerolite is slightly cheaper than Sapim CX-ray)
Hubs PT 2.4 rear and DT240s front. Rims will be zipp 303 and tubulars Vittoria Corsa CX.

Will provide feedback once I get some milage on them.

Henrik

buckybux said:

- How many spokes should I chose for resp. rear and front?

28 front, 24 rear, laced 2 cross.

(the lbs has a 28h PT2.4 on stock, but is 28 holes excessive for my weight?

Didn't you mean 28 rear 2 cross, 24 front radial?

Oppps...yep, can't type-sorry