After building my first 36er I knew i’d have to make one for myself too one day. Well that day has come and I’m wondering why it took me so long. One benefit of waiting was the new release of carbon rims made by Braun/Alchemist. They’re about 630g each and 32h unlike the other alloy rims available that are all 36h and can limit hub choice. The last bike had “normal” spaced King hubs front and rear and a dedicated singlespeed rear hub for the wider flanges and a stronger wheel. This time i went with fatbike spacing – 150×15 front and 177×12 rear with Oynx hubs. This way I will get to swap rigs with version 1 and test the difference in ride quality between the wheels, as well as the differences in frame geometry.
Tires are still the weak link in the 36er build kit. The Vee Rubber Trax-Monster are still the only MTB tires (with knobbies) and it’s been that way for over 10 years. I’m happy they exist but the 36 x 2.25″ tires are over 1400g each and not tubeless-ready. They have wire bead tire and a rather stiff casing that isn’t too bad at rolling but are far from being a good trail tire. They leave a lot to be desired when compared to the numerous options in all other wheel sizes and widths. Carbon rims this year, maybe some new tires soon?! I can only hope for a tubeless-ready 120tpi that loses many grams at the place it can help these big wheels the most.
Even with the tires it’s hard to explain how fun it’s been to visit old trails with new big wheels and see what this bike can do. It’s a different experience…the bike has momentum and a pull to it. It’s not noticeably harder to get up to the speed where that pull is recognized. Maybe if it wasn’t a single and i was in the low granny gear on a steep climb i’d feel how hard it was to turn these wheels around, but being a singlespeed I’m already out of the saddle or hiking at that point. In every other place it surpassed my expectations.
I made the last frame in Ti as well with segmented seatstays that stuck out too much and T’s thighs hit them while pedaling sometimes. This time I used a sleeved wishbone design like the old Bontragers but different. There’s so little room behind the drastically bent seat tube that the curved stays join the seat tube itself. The seat tube has such a bend to allow it to hit the BB instead of being welded into the downtube for maintaining frame stiffness and strength. I wanted to use a dropper on this version so this style seat tube was needed. After discussions with TB on v1, I lowered the fork offset 20mm to 78mm to shorten the front center while still giving plenty of room for the toes. I also steepened the head angle to 69 so the trail wasn’t too different. The last fork was so choppered the front axle seems too far away and had a longer wheelbase than maybe needed. I’m not doing forward geo on this wheel size…doesn’t make sense for this bike with 510mm chainstays and 150mm of BB drop (~12″ BB height). It’s by no means a wheelie machine and prefers to stick to the ground for the most part. But what it lacks in one type of playfulness it rolls like no other bike i’ve tried.
Right now it’s rigid with a Ti sleeved unicrown fork. Version 1 had a segmented steel fork. The new fork is 520mm long it’s pretty flexy at the crown, surprisingly so given the wall thicknesses and tube diameters I used. A truss fork would be nice, but as you’ll notice there’s no room under the stem for a clamp so I’d have to attach the upper trusses to a clamp above the stem and I just didn’t want to deal with that right now. I prefer the look of this fork anyways.
I have two different suspension forks to test out when I get bored of the rigid – a dual crown DirtySixer fork made with custom crown pieces to give it an offset of about 60mm. The fork is LONG though so it’s going to change the geometry of the frame pretty drastically. The travel has been taken from 170 down to 100mm (so to not bottom out on the crown), and it weighs about 10 pounds.. The other fork is an inverted Wren fatbike fork set at 70mm of travel. This seems like it could be a nice option except for the 45mm of offset. Most everyone is used to high trail steering geometry now, but using the Wren especially will take it to a new level. Normal trail would go from 93mm to 131mm with the DirtySixer fork (and slacken it to a 67 deg HTA), and trail would increase even more to 143mm with the Wren.
With a Cane Creek Slamset (lowest upper stack height around) i used 70mm x -15 deg Paul Boxcar stem and the bars are still a little higher than my saddle height of 750mm (BB center to top of saddle). Being almost 6′ 2″ tall but having proportionately short legs, it’s obvious 36ers won’t fit everyone. But if you’re over about 5′ 10″ and/or have long legs they’re a super fun bike to ride and way more normal feeling than you’d expect just looking at them.
All said my bike with pedals as seen in the photos is 29.4 lbs. Gearing is 28 x 22 which seems good for my local area and level of fitness. The tires are set up tubeless with a lot of sealant and a spliced tube as a rim strip. Using mostly carbon parts you could get it down another pound or two (cranks, bars, stem, and lighter pedals). But again where it matters most is in the tires. Someone please make some nice tubeless trail ready 36er tires! And 32″ tires! It may not be a “needed” bike but if you like rigid singlespeeds this one should be up there in the “wants” list.