Rims

I've got the wheel hubs, but have been kind of dawdling about the rims.  There really isn't a lot of info out there.  The big question is "tubeless" or "clincher" - which has a simple answer for me - clincher - since its the easiest to repair when touring. Tubeless rims with self-sealing goop are probably less likely to flat, but seem to be more of a problem if you have to deal with a major breakdown. I'm sure there's someone who would argue the point - but I'm admitting complete ignorance up front, so you can consider that you've already won.

Some manufacturers claim their welded rims are better than pinned rims.  Here I think I'll go with Roger Musson in The Professional Guide to Wheel Building: it makes no difference (you can buy a copy of the book at http://www.wheelpro.co.uk/wheelbuilding/book.php - it's definitely worth the $15 you've got to shell out).  Musson argues that the strength of the wheel comes from the spokes pulling the rim inward, so that the entire rim is in compression and whether welded or pinned it will have the same basic performance.  I would speculate that the failure modes under extreme stress might be slightly different - that is, they might break in a different way or at different points under extreme stress, but what the hell - the rim will be so deformed before breaking that it really shouldn't matter.

You can spend a boatload of cash on carbon rims, but that seems silly for a touring bike.  I'm sticking with aluminum.  At the upper end I was looking at Mavic EN 821 Disc rims, which are 21mm width, 32 hole and weigh in at 460 grams. PricePoint had them on sail for $60 (listing at $105).  A similar price can be had on the Mavic XC 717 and EX 721. At the lower end, the Mavic XM 119 goes for only $25 ($38 MSRP).  The EN 821 uses Mavic's FORE technology that claims stiffer and stronger  http://www.mavic.us/wheel-tyre-system/fore.  Looks like this is more important for tubeless tires.  A big question in the decision is how wide the rim should be.  The EN 821 and XC 721 have 21 mm rim widths and the XC 717 has a 17 mm width - hence the x21 and x17 (hey, the numbers mean something, why isn't this on the web somewhere?)  The 21 mm rim widths are typically good for 35 or 37 mm (1.5 inch) to 69 mm or 76 mm  (2.75 or 3 inch) tires, while the 17 mm rim is good for 25 mm (1 inch) to 52 mm (2 inch) tires.  On the one hand, I doubt I'll be putting any 3" tires on the bike, but I'm also unlikely to go below a 35 mm.  One of the considerations for the rims is that a narrow rim with a wide tire is more susceptible to pinch flats, so the wider rim would be preferable.

Eyelets?  aaarrrghh.  Traditional wheel builders seem to prefer double eyelets (which distribute load), but most rims seem to be single or non-eyelet.  Arguments against non-eyelet wheels is that the spoke is loaded against the rim aluminum directly, which is more likely to result in failure.  It does seem that non-eyelet is being done at the low end of the price spectrum.

Asymmetry? At the upper end, some of the rims have holes drilled to account for asymmetry in the spokes - that is the "dish" that allows the wheel to be centered while having the disc brake (in the front) and gearing (in the rear). This supposedly allows for more even spoke tension.  The Mavic EN821 has this, but none of their lower end products.

After digging down further in the PricePoint web site, the EN 821 is out because they only have the 29er on sale.  I'm thinking of the x19 rims, but I don't like the XM 119 as they're not eyeletted.  Then I was googling around and found that travellingtwo ( http://travellingtwo.com/13732 ) has reported problems with the Mavic XM 719.  So back to the drawing board...

Decided that its probably better to go cheap at this point.  The Alex TD17 can be gotten for $25 each - so I'll start there and see what happens. Damn - tried to pull the trigger and only one left in stock.  So back to the drawing board (again)...

UPDATE:  Found some recommendations for strong (but not too heavy) low end rims - the CR18 from Sun Ringle ( http://cyclescribe.blogspot.com/2011/01/humble-rims-for-your-humble-tires.html ).  I ordered a pair of rims that are black with silver sides, which were cheaper than the straight black anodized or straight silver (why?).  Weird thing about online ordering - I first went through my list of online bike sites, including Niagara Cycle, where I've gotten stuff in the past. Ordering direct from Niagara included a $20 shipping charge ($10 per rim) on top of the $21 per rim.  But going through Amazon I could get the rims for $23 with a $5 shipping charge (combined). OK, not so weird, except that the Amazon order is being fulfilled by Niagara Cycle. Seems like someone needs to rethink their shipping costs.  The rims I ordered are 559 (26") with 17.5 mm inner cross-section and 22.5 outer cross-section widths ( http://sun-ringle.com/wp-content/uploads/2012/09/rim-profiles_rev_.pdf )