# Aksium vs. Open Pro/Ultegra



## mhickey79 (Nov 28, 2009)

My season is winding down, have just one more race to go as a Cat C (USGP in PDX). Looking to do some serious bike upgrades for next season. My current wheels are Mavic Open Pro rims on Ultegra hubs, 32 spokes, double-butted. Several of the bikes I'm looking at retail in the $2500 range, and come equipped with Mavic Aksium wheels. How do these compare to my current wheels in terms of weight, stiffness, etc? Thanks!


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## aengbretson (Sep 17, 2009)

The Aksiums are stiff... very stiff. You won't want for efficiency in sprints. They are also very durable - I put a few thousand miles on them this summer and they are still true within 2mm. I like the lower spoke count, the bladed spokes, and the machined braking surface. However, they are not light at ~1800 g/pair.

They are a great training wheel, but for racing I'd look at Ksyriums, which shed about 200g (half a pound!) for a set.


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## OTG (Nov 16, 2001)

Open Pro/Ultegra with 32 DT Competition double-butted spokes, brass nipples, Velox rim tape: 1840 grams (no skewers) 1959 grams (with skewers)
Mavic Aksium: 1855 grams (claimed)

Weights are about the same.
The OP/Ultegra wheel has more spokes, so will probably be as stiff or stiffer than the Aksium.
The Aksium may be a little bit more aero, due to the lower spoke count & bladed spokes.

The OP/Ultegra wheel should be a good bit more durable, if built well. Shimano hubs are as good as they get, the spokes are very high quality, and brass nipples are probably better than whatever Mavic does on the Aksium. 
Mavic hubs... just aren't as good.

I don't know if the Aksium spokes are proprietary like the Ksyrium spokes, but if they are they're probably expensive & require a special wrench for truing.

Ksyriums are lighter, but are the second least aero wheelset in just about every test I've seen (least aero is the R-SYS), proprietary expensive spokes, etc. 
You can do a lot better with a decent hub, rim & spokes.

They won't prevent you from doing well, but neither Ksyriums nor Aksiums are a huge upgrade from anything.


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