Respectfully disagree. See, for example, Surly Instigator and Gravity Deadeye. But, I see your point regarding a second fat wheelset for a 27.5 inch bike.Surprised that so many posters missed the point that 26+ wheels are not designed for a 26 inch frame, but to offer a high traction / cush option for a 27.5 frame.
Sounds great, but neither of my FS bikes can take that big a tire in the rear or I'd give it a shot.And no one seems to have picked up on the point that it gives the option of owning two sets of wheels for the same 27.5 frame, switching between both 27.5 and 26+ wheels based on trail conditions or mood
FS 29+ & 17.1" CS. They don't have to be super long.I see a market for 26+ on 27.5" frames. I kind of like the idea better then 29"+... where the chainstay gets pretty long. 26"+ has potential to be more flickable and also swapable.
You forgot to mention the extra cornering traction. I've been on a 29+ bike for over a year now and it's not just a marketing gimmick. The bigger overall diameter seriously helps when riding really rough terrain, like rocky stream beds or ledgy trails. The tires really do feel like they'll roll over anything (and that's before you add suspension). Also, being able to run low pressures (10-12psi) gives you more than just a trivial traction advantage. All that without the sluggishness of a full fat bike.It's not SO much better. Marked improvement on that sandy stretch of your local trail. Lower pressures increase traction in many situations, while increasing compliance. Particularly useful for hardtails, where it reduces harshness and extends the reasonable usage of the bike into slightly more chunky territory. Reduces the importance of small bump sensitivity in shock tunes for FS. Set up your bike for bigger hits and more aggressive riding?
Trade off is minor increase in buff rolling resistance and decrease in tire durability in the rocks.
Experimentation on 26+? What's there to experiment? It is what it is.I see the industry supporting 27.5+ because it's easier than 26+. It lets them focus on two rim sizes and it also works on frames designed for 29 with just adding boost hubs. Anything that can limit production costs but still providing the consumer options is a win for them.
That said, I can see 26+ being beneficial on big travel bikes that are now being adapted for 27.5. From watching the fat skis' evolution over the last couple decades, I can see the fatter tires open up new lines for the free-ride and DH set. I could see it being a good option for the Red Bull Rampage courses.
After making the switch to 29ers on my last xc bike, I see the traditional 26er being dead for all but kids bikes where it belongs. However, 26+ could have some merit down the line, but all the industry's energy needs to finish out it's run on 27.5+ for awhile. When the engineers get bored, we might see more experimentation from them on 26+.