I just finished reading an interesting thread on the MTBR forum. The author was working on a mountain bike with 36″ tires! Check it out here.
My first thought was “Why go that big when the 26 or 29 inch bike works fine?”. But then I stopped myself and realized that my thoughts are the same thoughts most 26 inch bikers have when the 29 inch bike was introduced. So, with a more objective mind, I decided to read about the 36 inch bike.
As with any increase in bike tire diameter, you are going to gain some major benefits in keeping momentum & rollover ability. The trade off is weight and fit (as in ability to fit people).
Most of these have been mentioned before in the 29er advantages/disadvantages so we won’t rehash those. But something interesting to note is that as the wheel diameter gets bigger, the more funky the geometry has to be and the less people it will fit.
The geometry numbers posted:
Wheelbase: 46 inches.
Weight: 36 lbs, (with full Surly flask and holder!)
Chainstay length: 520 mm
Drivetrain: 3 X 6, 20-90 gear inches
Standover height: 30.5 inches
Top tube length: 24.5 inches
To me, the chainstay length jumps out. The new Ibex Section 29 has a chainstay length of 17.7″ compared to 520 mm (20.47″), the Section 29’s chainstay is small. Of course bigger tires are going to equal larger chainstay length.
But the number that surprises me for being quite normal is the 36er’s Standover height. Although a standover height of 30.5″ pretty much limits this bike to riders over 6’2″ tall, I was suprised that they were able to build a frame with that low of a standover height to begin with. After all, we’re talking about a bike whose wheels are a full 10″ larger than a 26 inch mountain bike.
Another number that is almost normal, is the wheelbase. A 46″ wheelbase is pretty big, but if you think about it, it’s not really all that much out of the norm. An XL Gary Fisher 29er has a 44.27″ wheelbase while a XL Niner bikes R.I.P. 9 is 45.5″. It’s not that much of a “stretch” to get to the 46″.
So maybe the geometry is not too funky.
Before I become too technical about this, I have to remember that what really matters when mountain biking is the enjoyment derived from it. Some derive joy from climbing, some from descending, some from being able to roll over cars with ease. And if the 36er provides lots of enjoyment, then that’s a good bike. For me it would be a cool bike to have in the stable for those days you want to cruise around the neighborhood/park/trail/beach and surprise people!
Good luck benwitt1 1 and keep the updates coming.