MW-1: A tribute to the XO-1

I haven’t been able to ride my new mountain bike this Fall because of continuing knee issues, same knee I’ve moaned about for a couple of years. After a great 3 hour ride with Mike on August 6th my knee swelled up so much i had to use a crutch to walk and it wouldn’t bend so that stopped me riding. After almost two months of rest, 100cc’s of fluid removed, and a cortisone shot, I’m back on my feet working on strength and riding again. Since i don’t know what caused such an extreme flare up I’m taking it pretty slow. The next step is either an osteotomy or total knee replacement, neither of which sounds very fun. It’s possible the PRP injection I had in May was part of the issue that caused the overkill inflammation. Two surgeons i talked to considered it a likely factor. I know many people have had great experiences with PRP but I most certainly did not. So if you have osteoarthritis I recommend steering clear of PRP. Just a public service announcement, but your results may vary.

I’ll solely be riding on the road this winter to rebuild strength and endurance. I don’t have a road bike so decided to build a copy of a 1993 Bridgestone XO-1, which still isn’t considered a real road bike but it’s close enough in my book. If you know me, then you will know that I don’t care much about aerodynamics or the weight of my bikes. Not that i don’t like going fast, i just don’t try to anymore. I really didn’t need another bike but it’s a design i’ve always wanted to try, and i could rationalize it since it was going to be a “parts bin bike” – built with tubes and parts that already could be found in the shop. There were a couple exceptions since I had given away my old Nitto and On-One mustache bars and had no flat-mount brakes to use. I picked up the Whisky Winston mustache bars and am very happy with them! But everything else I already had including the Shimano 2×9 XT cassette and derailleurs, and Dura-Ace bar-end shifters. I can’t even remember the last time I had a bike with a front derailleur! The Knight Composites wheelset with Project 321 hubs is several years old but in great shape; I sold the frame a few years ago that used that wheelset. The Easton crankset was used as a mock-up for compact road/gravel bikes and not although not my first choice for this bike it will do just fine.

So why build a (modified) version of a 30 year old bike? I always have wanted an XO-1. I had a good friend in Boulder that had one and it left an impression. I’ve always loved mustache bars and appreciated the versatility of the XO-1, it was an allrounder that fit bigger tires, racks, and fenders. It just made sense to me. After Bridgestone stopped making bikes, I was a big fan of Rivendell and subscribed to the Reader. Grant Peterson’s utilitarian philosophy surrounding bikes was a refreshing contrast to being engulfed in cross-country and cyclocross racing. The XO-1 was the pre-cursor to the Rivendell Allrounder which really knocked my socks off. I knew someone in Boulder that had one and I was green with envy. A couple of years later, I put down a deposit for a Rivendell Atlantis (which replaced the Allrounder) but had to bail and used that saved money to fund another summer of bike racing.

The closest I got to an XO-1 was setting up my 2000 Independent Fabrication cross bike with mustache bars. I’d ride that everywhere, commuting from my home in Nederland to Boulder and back on the windy washboarded dirt roads and singletrack. Once winter took over the high country, we’d venture out east into the plains of Boulder County avoiding paved roads by linking up as many bike paths and ranch roads as possible. These cross bikes with 700×35 cross tires (the biggest available at the time) made road riding fun.

In 2009, I tried to make my 2009 Surly Cross-check an XO-1 as you see in the photos below, but it just didn’t feel right. It was a good commuter bike but i never really clicked with it. I nicknamed it “Tank” for that is how it rode.

Fast forward to 2011 when I started building my own frames. I built myself a cross bike, an allrounder, a Rivendell Bombadil copy, but somehow never an XO-1. I couldn’t get myself to build a 26″ wheeled bike when 29er’s were taking over the world. The original 1992 XO-1 came with 26″ wheels and was meant to fit 1″ to 1.6″ tires. The 1993 model changed to cantilever brakes and added clearance for up to 2″ tires. This, as you hopefully recognize, is an ancestor of today’s gravel bikes. Although many rode their 700×25’s on gravel roads well before 1992, this is the first bike of its kind to have road geometry and fit mountain bike tires. (The Bruce Gordon Rock n Road pre-dated the XO-1 by a few years but used Bruce’s own 700×43 tires so was really a modern day gravel bike.) The geometry of the XO-1 is decidedly steep by how I like to build gravel bikes, but fits right into what I consider an Allroad bike. It’s pretty wild to see how drastically different mountain bike geometry is compared to 10 years ago versus how static cross and road bike geometry has been.

_{(*the below scans of the original 1993 Bridgestone catalog were taken from the Retrogrouch but the full list of catalogs by year is available at Sheldon Brown’s website – of course.)}

My version of the XO-1 isn’t a carbon copy of the 1993 model but I think maintains the spirit of the original. I kept the overall geometry, tubing diameters, and fit close to the stock model but built it around 650b wheels instead of 26. It can fit up to a 2.0 (as well as 700×45) while fitting a compact road crankset. I kept the BB height the same as the ’93 XO-1 but with a 650×47 tire diameter (so the BB drop increased). The steering geometry also changed with this wheel and tire size but I kept the trail constant by adjusting the head tube angle to 72.5 deg from 73. The rest is pretty much the same as a 55cm XO-1 but with a slightly different reach. Parts spec is different of course as I wanted to use flat-mount disc brakes, 12mm axles, a carbon mustache bar, and a 1-1/8″ steerer on the fork with no quill stem. It’s also not a lugged frame…I am a TIG welder after all. I found the perfect tubing for the front triangle: True Temper OX Platinum. The top and down tubes are double butted .8/.5/.8mm wall and the seat tube is True Temper but a .9/.6/.9mm butted tube with one end cut off and fit to a Paragon weld-in collar for a 27.2 post. The seatstays are single taper Tange 14mm with cast braze-on tips. The chainstays are straight gauge 3/4″ x 0.028″ wall (19 x 0.7mm) shaped to fit bigger tires and clear the heels (s-bend).

Having ridden the bike several times now, I’ve felt how different it is from my current allrounder (OGATB). It’s pretty much how i expected it to feel in fit but is way better handling than i expected. The relatively low Trail (54mm) does not feel as twitchy at all, probably because of the bigger tires at 32psi. The steering on downhills feels amazingly stable and there is no indication you’re counter-steering as there is with higher trail gravel bikes. It doesn’t flop into corners like some bikes with 650 wheels, it steers into them and feels planted. The Panaracer casing feel smoother than the WTB 700×44’s I currently have on the OGATB. On rough broken pavement roads I didn’t miss the rollover effect usually attributed only to larger diameter wheels.

The fit feels centered and at first it felt short. Not because it is short, but because the rider position is much more forward than my other bikes. It has a shorter front center than I’m used to putting more weight on the front wheel. It also has a longer bar reach and stem than any bike i’ve had in several years (90mm). It wasn’t that long ago that 90mm was the shortest stem you could buy! Now it feels oddly long with your hands closer to the front axle. I know it’ll handle worse off-road than my OGATB but that’s to be expected with the steeper angles, shorter front center, and lower trail. From previous experience, mustache bars should use a shorter stem than the same bike with drop bars.

Style. Even though Charlie Cunningham had done it many years before, a longer head tube and sloping top tube just makes more sense when not using lugs and a quill stem. I’ll make a stem for this bike that gets rid of all the spacers once i finalize the bar position. The fork is several years old but fits this build well. It’s 400mm axle to crown with 51mm of offset. It was built using True Temper tapered blades that flex more than straight blades, offering a smoother ride. Triple bosses on each leg, a port for a generator hub, and has fender eyelets.