With my thoughts on crank sets all cleared away, I wanted to hit upon the cassette choices for climbers and 29"er rigs. Some of you may be saying, what choices? Well, it's true that SRAM and Shimano have only provided 34 tooth low gears for cassettes, but there is an alternative.
Readers that checked the Action Tec link the other day already know where this is going. Yep! Cassettes with humongous low end cogs! We're talking 36T, 38T, and 39T low gear cogs! These types of gears may seem rather useless to many of us that don't have extended climbing on the menu, but believe me, there are folks out there that love these choices.
I can certainly see the value in gearing your 29"er out with the 36T low end gear for sure. This would certainly cover your loss of low end from 26"er gearing and get you back on a level playing field in those terms. Adding in the better roll over ability and traction of 29"er wheels and it becomes very attractive, I think.
The 38T and 39T gears are more specialized gears, I think. If you have climbs reaching into the mile plus category, and/or carry loads for touring on a 29"er, I can see where these gearing choices might be desirable. But the vast majority of us would never need such gears. Walking would be just as fast and possibly safer in many instances. Short steeps that are unrideable in a 36T low? Maybe they shouldn't be ridden at all. I would have to question the sustainability of the trail at that point. At least in the Mid-West anyway.
My position is that a 36T low gear is a great idea for 29"ers. My gripe is that a cassette from Action Tec costs an arm and a leg! Yes, I could modify a SRAM cassette and have that cog, but how about SRAM or Shimano, (or some other manufacturer) just make a cassette with that low cog and sell it to me for less than a single titanium Action Tec 36T cog would cost me? (That's about $60.00 less shipping, in case yer too lazy to check out the linkage!)
Maybe this has uses beyond a triple crank 29"er set up too. Think 1 X 9, or even compact crank roadie bikes set up for touring? I think it makes sense and would be a great additional choice for cyclists, not just 29"er freaks.
Gears for climbers. Lets have 'em! That's what I say.