Originally Posted by epic
So I demoed what may have been my first 650B bike. Meh. It was cool and all, but I didn't feel like the positives vs. 26 outweighed the negatives. It's probably great for smaller people who have been sold a bill of goods and shoe-horned onto 29ers though....
+1 for the new 650b wheel size!
I recently converted the front end of my 26'er Maverick ML-8 to a 650b (easy mod involving only a new front wheel and 3/4" fork shims so that it doesn't bottom out on the bigger wheel). My experience so far is completely the opposite of epic's: essentially nothing but positives - it rolls better through rough terrain, formerly nastly drop-offs now feel mild, it pulls me through corners like on rails, the feeling of an impending endo or front-wheel washout has been drastically reduced, and, unexpectedly, allows far better low-speed handling in technical terrain like obstacle-course switchbacks (I am able to hold a track stand a lot longer thereby allowing course corrections more readily). I haven't yet seen a benefit in steep-uphill technical terrain perhaps where "rolling through" the terrain doesn't occur and lifting the front of the bike over obstacles is perhaps a bit harder. Also, to be fair I didn't change anything else on the bike so the head angle was slackened by 1deg which could be a source of some of the improvements, but probably not most.
I will agree with epic that this format is "great for smaller people" - I am short, with very short legs, and am challenged to find even a 26'er that has sufficient standover clearance, so a 29'er was out of the question. But I did have 29'er envy based on real evidence (I wasn't "sold a bill of goods"). I ride the super-techie rides just west of Denver where 5" to 6" travel, drop seat posts, high-volume tires are very useful for making rides enjoyable vs. hair-raising. Most of my fellow riders have switched to 29'ers and the performance gains that I've seen has been astonishing: they immediately could handle bigger drop-offs then me, they were flying through rough terrain that made my teeth chatter, and they were pulling away from me in flowing terrain as if on rails with an electric motor. The only place I could still hold my own was steep uphill technical terrain. Some of the smaller 29'er riders do report that the disadvantages of slower acceleration and loss of low-end gearing can be taxing, so this has been more reason to wait for a better tire size for the rest of us.
There's nothing holy about the 26" MTB wheel (it became the standard for practical reasons only, not due any long-term evolution like that for the 700 and 650 sizes for road and Tri bikes). The 29'er has clearly proven this though, for me, it's just too big. I see the 650b as just another MTB technology advancement like indexed shifting, clipless pedals, suspension, drop-seat posts, big-volume tubeless tires.... My Maverick is in it's 5th year so this 650b conversion was merely a test to confirm that my next bike will be based on the 650b wheel size - I for one no longer see the value of a 26" MTB!
BTW - I had no problem building up the wheel using a Stan's rim (my go-to rim anyway) and the tires were limited to some of my preferred choices anyway like the Maxxis Ardent and several Schwalbe models.
Edited by ski-ra - 5/31/13 at 10:05am