Originally Posted by Supertick
I have been told that a 32 spoke wheel in 26" (559) is sufficient for touring as long as it has a heavy duty rim. I have a mountain bike with good hubs and Sun TL-18 rims. Sun does not make these rims anymore and they have not answered my email. Does anyone remember these rims and if so are they considered heavy duty rims?
Overall, 26" rims are stronger than 700C. One of the reasons that they are used in mountain bikes is their smaller diameter and greater strength. A 32 spoke wheel should be fine for touring but you are missing 1/3 of the equation for wheels...and it probably the most important part of the whole equation.
Most people think that if they have a good hub and a good rim they are done. But what holds the whole thing together...air? You need to look at the spokes too. In a touring situation you will probably never break a rim and I can almost guarantee that you won't break a hub. But you probably will break a spoke...maybe lots of them. Get good ones. Don't go with straight gauge (you can read why
here, look at the section on Double butted spokes). If you want the best spokes for touring currently available, in my opinion, go with the DT Alpine III spokes. They have less problems with head breakage because of their tighter fit at the hub than other spokes. I've been riding the same mountain bike wheel -hard- for 5 years that was built with them and I think I've broken a single spoke.
For the front wheel, you probably don't need the Alpines but I've found them for cheaper than double butted spokes, so why not just use them all the way around?