Wednesday, May 07, 2008

One Step Forward, Two Back


<===Shimano formally introduced it's first 29"er wheelset at Sea Otter last month.
One of the bigger complaints about 29"er wheels is that they weigh more and are harder to accelerate than a 26"er wheel. This is due to the obvious fact that there is more material to deal with than a 26"er wheel has- more tire, more rim, longer spokes.
So, in an effort to reduce the difference between 26"ers lighter weight and a 29"ers weight in wheels, many manufacturers have built wheel sets that address this in varying ways with varying amounts of success. Mostly we are talking high performance, racing type stuff here. Wheels like Bontragers Race X Lite and Mavic's Cr29ssmax wheels, which are quite reasonable weight-wise and retain a modicum of stiffness that makes them great wheel choices for 29"ers. Even lighter sets can be had like American Classics, which get down below 1600 grams a wheelset, which is pretty light for a mountain bike wheel set of any wheel diameter.
So it was with a puzzled look on my face that I examined the bike pictured here at Sea Otter fitted with Shimano's newest and only 29"er wheelset. It has many features that are related to it's 26"er XT sister, tubeless compatible, free hub improvements, and axle tweaks. The one thing it shares with it's smaller diameter sister is the spoke count, which at 24 spokes is not enough for a 29"er wheel. Then I heard the weight- 1850 grams! Okay.......color me not impressed.
Several pre-builts for 29"ers are the same or lighter with more spokes. This raises a red flag in my mind. If Shimano uses less spokes and yet their 29"er wheel weighs more than some wheels using more spokes, then where is the weight coming from? My guess is that it is most likely in the rim, which is the worst place it could be in, (for this category of wheel) and defeats the purpose of making a high performance 29"er wheel in the first place.
And speaking of the rim, it is a narrower rim- 24mm- and that is fine, but consider this: A Rhythm wheelset, which has 28 spokes and a 28mm wide rim weighs only a 100 grams more and is built to be a trail/general use wheelset! Mavic's Cr29ssmax wheels weighed in at an even 1800 grams with skewers and tubeless valve stems installed. The Cr29ssmax wheels are also 24 spokes, by the way, which again, I'm not a big fan of, but the Zircal spokes are a different animal than what Shimano uses. The point is, the weight on the Shimano wheels is going to top out over 1900 grams when you add in skewer weight and tubeless valve stems. That, as Bicycle Retailer and Industry News states in their Sea Otter Special coverage, ".....is not super light."
I don't want this to seem like a Shimano bashing party, because it isn't. The trend seems to be going this way with pre-builts. FSA introduced it's own 29"er wheelset at Sea Otter, without much fanfare I might add, and it weighs in at 1920 grams. Again, using only a 24mm wide rim, FSA claims that it is erring on the side of durability. Well, there are choices out there with wider rims, (better for durability) that weigh less. What these companies are offering that is better, (other than their names, which is arguable) is beyond me.
Sure, 29"er wheels are going to weigh more than a comparable 26"er wheel, but with smart design and better use of materials, it doesn't have to be such a big gulf, and certainly we don't need heavier wheelsets that purport to be high performance/race category wheels. The proof is out there and companies jumping into the market would do well to examine the competition before setting out with a wheelset that doesn't measure up.

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