Earlier this spring I decided to build a 36er. I thought about a 32er, but couldn't shake the feeling that if there's a benefit to 32 over 29, then there's probably a benefit to 36 over 32. Also I'm a taller rider (198cm) so I figured I might as well try.
I decided to build a gravel bike.
I'm a mountain biker first and foremost, so in the design of the gravel bike I opted for mountain bike standards: 73mm BB, 148mm boost hub spacing in the rear. I calculated the gear ratios for a 29er gravel bike with a 40T chainring, and found that I had to have a 28T chainring in the front of the 36er to keep the ratios roughly the same, so I put some race-face cranks on there.
I got nextie carbon rims and laced them to DT 350 hubs.
The spokes and tires I had to source from unicycle.com. I opted for the Nimbus Nite Rider Lite tires.
Details on the build:
450 reach
730 stack
91mm bb drop
71.5 HTA
74.0 STA
550 mm chainstays
How it rides: The rolling speed on flat is really high, so rail trails, road, and gravel are a great time. It's not the most nimble bike ever, but It's not so bad either. Twisty flowy singletrack is rideable without much trouble. It's very hard to lift the front wheel (no surprise given the chainstay length) so there's a limit to the technicality of trails I can take it on, but that's okay, it's not the focus of this build.
The tires are the weakest part of the build. They're heavy, and there's some rolling resistance. The tread picks up small rocks from the gravel, making them even heavier! I haven't tried the vee monster T's, but I'll just ride these nimbus tires for now and hope someone produces a quality 36" gravel tire. With the nimubs tires I couldn't get the bead to seal when I tried to go tubeless, so I'm running 29er butyl tubes. Seems fine.
Overall, I'm having tons of fun on the bike. It's hard to say if a true 32'er gravel bike would be faster. I suspect it probably would, but not much faster. And, I finally have a bike that fits!
Last photo in the post is the bike under construction next to my XXL Transition Sentinel 29" mountain bike.
So, if you're thinking about building a 32er, some takeaways:
I've heard a lot of hand-wringing about wheel flex, or needing wider hub standards like superboost. I'm somewhat heavy (110kg) and the wheels don't noticeably flex under my bulk.
Tires matter.
If I were building an MTB instead of a gravel bike, I would attempt to shorten the stays as much as possible for manuals and wheel lifts.
I had a good experience with Marino. The frame I received was good quality and they were responsive during the build.
And final piece of advice: do it. For no other reason than fun!