According to customers' suggestions, we have opened 26er wide rim mold and 29er wide rim molds. Now, the next project will be 650b rims. There are quite a few customers like rims of this size.

We welcome all customers to provide some suggestions on the rim dimensions, like the outer width/inner width/depth/rim weight. Some customers say outer width be 30mm, and 23mm for the inner width, but some like outer width to be 28mm, inner width be 21mm. What do you think?

26er VS 27.5er VS 29er

Pros: Excellent on steep and stepped climbs. Easy to accelerate out of momentum sapping situations. Braking was strongest, especially at the bottom of steep descents. By far the most responsive to pumping the trail. A light-feeling that encourages the rider to hop over or around obstacles.

Cons: Descending is intimidating, especially after spending time on the other two wheel sizes.This bike requires more rider input and a bigger commitment. Rider position has a bigger effect on how the bike handles and responds. While a rider can "roll" a techie section on the larger wheels, the 26er rider has to attack and maintain enough speed to stay on top of the ruts, rocks and flat-edged bumps. The rider has to work on looking ahead, as the 26er places the rider lower over the front.

Pros: it has animble feel that is way closer to the 26er than the 29er,but it doesn't require the rider to work as hard. Your body position always feels neutral. You can pump the 27.5er along the trail, and when the trail heads downward, it allows the rider to remain relaxed. You don't need to attack rough sections. These wheels do a good job of staying on top of the rough stuff, and the front end goes where you want it to go.

Cons: We couldn't come up with a ride negative. It doesn't steer as fast as a 26er, but we never found a trail so tight that this made a difference. It didn't roll over the rough sections as smoothly as the 29er, but again, it wasn't a big enough difference to put the 27.5 rider off the wheel of the 29er.

Pros: The big wheels are great for descending. They smooth outnasty trail that would have you puckered on the 26er. The added confidence inspires you to remain more relaxed as the wheels float over rocky terrain. The big hoops offer the best traction of the bunch, both in corners and on loose climbs. This bike requires the least amount of body English to stay hooked up (going up or down). Crewers noted they remained seated longer in the 29er. Once up to speed, the bike holds momentum well—and holding momentum is what the 29er is all about.

Cons: Getting up to cruising speed takes more effort. Steep climbs or regaining speed following a momentum- zapping misstep is noticeably tougher. The only plus here is out-of-the-saddle efforts work great because the rear tire maintains traction. The large wheels don't respond as well to pumping the trail, and lofting the wheel requires more effort. This bike doesn't have that lively squirt of acceleration you feel on both the 26er and 27.5er when working the backside of a whoop. The larger rotor up front wasn't enough to give this bike the braking power we wanted.

Win: This 27.5 mountain bike proved to be the most versatile of the three hardtails. It did an excellent job of blending the best traits of the 29er and 26er with-out ever feeling like a compromise between the two. This bike scampered away from the 29er on steep uphills or after a speed-zapping mistake. It then gapped the 26er on the other side of the mountain on the way down—all the while delivering a very resilient ride that didn't beat up the rider.

New Update : After long time testing and improving, 650b rims manufactured today are very good, with strong strength, We are ready to sell rims to customers and we are sure all customers will like the rim and like the strength. Please click here for purchase and we will do strength test for each rim before shipping, to make sure 650b rims are good for customers.Buy it now,click here: carbon MTB 650B rims