Frankenbike: Build Your Own
Frankenbike is a word that you won’t find in the Merriam-Webster online dictionary. But, if you look beyond the norm and venture into popular culture, you might just find this definition; “Frankenbike – a bicycle assembled from various parts one has lying around or parts received from friends, the more mismatched the better.”
One type of bicycle that falls into the Frankenbike category is the 96er (or sometimes referred to as a 69er). Whatever you want to call it, it’s a mountain bike that has one 29-inch wheel and one 26-inch wheel. Most often the bike is configured with the bigger wheel up front and the smaller wheel in the rear. The idea in having mismatched wheels is to have the best of both worlds on the trail. 29-inch wheels are known to have more surface contact with the ground and the ability to roll over obstacles more easily. 26-inch wheels on the other hand have an advantage when it comes to weight (less of it), speed, and better handling. Together they can tackle and conquer any kind of riding condition with exciting efficiency.
So where do I get one?
96ers are definitely on the fringe. Carver started offering production models in 2005. Trek entered the market in 2006. This only lasted a few years (until 2009) and they have since shifted their focus to meet the demands of full 29er market (through Gary Fisher). Currently, in addition to Carver, only a handful of other smaller companies offer them in limited quantities. Fortunately for those cyclists who seek out the unusual, there is beta out there on how to build your own Frankenbike. With a few new components and a little bit of time, it’s possible to create something very interesting. Cue the diabolical laugh now …
DIY 96er: Parts
1 Mountain Bike made for 26-inch wheels
1 29-inch Wheel (rim and tire)
1 Fork (rigid or suspension) designed for a 29-inch wheel
Tools, Bike Workstand
Wheels – 29er mountain bikes (previously reviewed in the article Big Wheels Rollin’) are on the rise. As a result, it should be pretty easy to order a single wheel online or purchase something from your local bike shop. For those who are cost conscious or just like dirt-bagging, a 700c wheel can suffice. Keep in mind that you tire choices will be more limited since the rim is narrower by nature.
Frames, Forks, and Geometry – The relationship between a bigger wheel and the fork is an important dynamic when it comes to doing a 96er conversion. First, the increased radius (1.5-inch) of a 29-inch wheel will not fit an existing fork designed for the standard 26-inch variety. Second, the enlarged wheel also affects frame geometry and riding position because it brings the bike higher off the ground. Bike handling has the potential to become unmanageable, especially when pedaling up steep, technical trails. In addition, knee, hip, and neck angles may fall out of optimal alignment causing discomfort or injury. Fortunately, both of these situations can be avoided by selecting a new, 29-inch specific fork.
For hardtail bikes that will be converted to a rigid fork the process is pretty straightforward. Try to match the measurement from the axle of the wheel to the crown (intersection of the steering tube with the stanctions) of the original fork. This type of conversion is often done for singlespeeds.
For those who wish to keep their front suspension there is an additional thing to consider; travel. This specification refers to the plush-ness of the fork. The longer the travel, the more plush the ride. However, a long travel 26-inch bike generally has 20- to 30-mm more travel than a similar 29-inch variety. The difference in length is a result of balancing frame geometry with a larger wheel size. Not many cyclists would be able to handle a 29er rolling with a 150-mm fork. So when you choose a new 29-inch specific fork, just remember to get something that has less travel than the original one. For instance, if you ran a 115-mm fork on your 26-inch bike, you will want to get a 29-inch fork with about 80-mm of travel.
Once you’ve procured a wheel and figured out the right sized fork, the process to assemble is pretty simple. Start by removing the 26-inch wheel and the original fork. Install the new fork, tighten the bolts, and attach the new wheel. Finally, shout ‘It’s alive!’ and go ride the Frankenbike.
Oh, and one last thing. Remember to bring two different sized tubes …