Will They Fit in the Frame & Fork?
While it is possible to buy a complete new 29” front wheel that you can mount your existing Brake Disc on, you can’t with your rear. That will requiring building a new rear wheel, lacing your Bafang Hub Motor in the new 29er Rim and calculating new spoke lengths and truing the new wheel in a truing stand. That procedure will require the services of a experienced bike shop.
And you should consider the following : Head Angle, Trail, and Pitch Stability
“Trail is a function of head angle and fork offset, and it’s the largest determining factor in how a bike corners. 29-inch forks are built with a longer offset than their 27 inch counterparts, which means that 29ers require a steeper head angle to achieve the same trail measurement. A more kicked-out head angle yields a bike with greater pitch stability, or fore-aft stability. This means that when things get wild, you’ll be less likely to be ejected over the handlebars. This is mostly a factor for high-speed descending and steep terrain”.
“Considering the impact of steering geometry is critical for making comparisons between bikes of different wheel sizes. A 29er with a 68-degree head angle will maintain composure at high speed, but low-speed handling, particularly cornering, will tend to be sluggish. By comparison, a 68-degree head angle on a 27 inch bike will yield a noticeably more responsive handling feel, but will be less predictable when initiating turns at high speeds. So, if you’re comparing bikes between wheel sizes, expect a 29-inch bike to be roughly two degrees steeper than a 27 inch bike with similar cornering characteristics”.
“At a given speed, 29’ers do roll slightly more efficiently, and it’s most noticeable on flats or gentle grades, either up or down, with successive small bumps. The difference comes down to angle of attack. In other words, the larger wheel approaches a given obstruction at a shallower angle, enabling it to roll “through” the object, rather than “over” it. However, this example assumes a constant speed, and mountain biking is a dynamic activity”.
“There’s a price to pay for this improved roll over. Larger wheels weigh more, and that added weight is placed farther from the hub, which further increases the wheel’s inertia. In other words, 29’ers require a stronger effort to get moving. This phenomenon is most noticeable when exiting turns, and during technical climbing, where bursts of acceleration are part of the game. Big-wheel evangelists will of course point to the fact that you’ll run lower gearing to compensate, but gearing doesn’t change the laws of physics. The fact remains that 29’ers maintain speed more effectively, where 27 inch wheels accelerate more efficiently.”
Considering all that, it’s is probably less of a concern if your MXS will be ridden mostly on city streets and paved trails .....
One of the advantages and maybe pitfalls of waiting on our Sondors to be delivered, is deciding how to personalize, customize and modify our new bikes, in the time it takes them to get to us. I had new Carbon Fiber Replacements for the Handle Bar, Stem and Seatpost in my Parts Bin more than a month before my Sondors would arrive. I had replaced the Original “Tractor Seat” with one that my butt was already accustomed too, almost as soon as my First Generation IndieGoGo Sondors Fat arrived but all the other improvements I’ve made, were after riding quite a few miles and evaluating just what to consider. Now after over 15,000 miles, only the Original’s Frame, Fork, Battery Box and Bottom Bracket remain. Be Forewarned.... Once You Start It Ain’t Easy To Stop... the upgrades, not the bike itself, Magura MT-5e, Quad Piston and Pads Hydraulic Brakes with Larger Discs haul my Electric Black Lightning to a stop! 😀