An interview with mountain bike pioneers Steve Potts and Charlie Cunningham
by Jen See
Last Spring, I paid a visit to mountain bike pioneers Steve Potts and Charlie Cunningham. I packed up my rental car — a not-very spacious Toyota Carolla — with two bikes, cameras, notebooks, and all the necessary detritus required for writing adventures, and drove north to Inverness, California.
I slept on Potts’ couch at his house that sits on a hillside canopied by redwoods and overlooks the wetlands of Tomales Bay. Through the wide windows I saw stars in the clear night sky and watched the mist rise from the bay in the morning sun. The honking of the ducks echoed in the stillness. It’s one of the few places I’ve been lately where Mumford and Sons sounded entirely perfectly right.
Then we drove — Potts, in his vegetable oil-fueled pick-up truck and me, following in my Carolla — along the winding, redwood-lined roads to Fairfax. There we visited the workshop where Charlie Cunningham has made bikes and bike parts for as long as anyone can remember.
I perched on a shop stool, and listened as the two craftsmen talked bikes. Certainly, they’ve forgotten more than I’ll ever know about our favorite two-wheeled contraptions. Here is a partial transcript of the conversation in Cunningham’s workshop. Watch for the print story in the next issue of Mountain Flyer. — Jen See.
Charlie Cunningham has an inventor’s soul; he’ll take something apart just to see how it works, and how to make it work better. His workshop is stacked floor to rafters with bikes and their parts. If you can imagine something made of metal, you can make it in Cunningham’s wizard’s lair.
Cunningham is the practical one. Steve Potts is more artistic and aesthetic. A vintage Cunningham is bare, stripped down, perfectly engineered aluminum. A vintage Potts is hand-painted, meticulously carfted steel.
Charlie Cunningham: There’s a bunch of things about the modern bike that I’m really bummed about.
Steve Potts: Well, we’re facing it right now. You know, how Shimano changes things every six months. It’s to make things easy for the world of production. The headset, it takes a guy like three minutes to adjust a headset. Now they just use the star-fangled nutbolt. Boom, done.
CC: There’s two big problems with modern bikes, both mountain and road, that have been overlooked. Maybe on purpose. I can’t tell you why. They’ve got these ultra-sophisticated materials now, and everything works really well.
What they’ve done is, they haven’t changed the rear dropout spacing on both road and mountain bikes for a long time. It’s been 130 and 135 for the longest time. But they keep packing more gears in.
It really does two things. It screws up the dish in the rear wheel so you get a really flexible rear wheel, sideways. They’ve made cranks so that they just plug on to the bike. So the cranks have moved out from the centerline of the bike.
So you have the chain going out from the bike in the front and in on the bike in the rear. And it’s the worse thing. It’s just bad. It’s a real problem. You get the tension on the drive side spokes is crazy high.
CC: I look at these beautiful bikes and they’re just so fucked up from a basic perspective. I don’t even want one. I would like to have a really cool carbon fiber road bike when they get this stuff worked out.
It’s such a fundamental flaw that we can do better. They haven’t changed the standards. If you screw up the chainline, you have to buy more chains! Your chain load is the worst when you’re in the low gears, which is when you’re climbing, where the tension is the heaviest.
SP: When Charlie and I started, we were going to make these parts that last forever. And then we found out what stupid we were. Why do you want to make them last forever? Don’t you want to sell more parts? And we’re still that way.
I mention how standard road-bike q-factor is too narrow for me, and I have to lengthen my pedal spindles.
CC: The Q is a big thing too. And cornering clearance. And if you’re riding off-road on a slope, how close that’s tucked in really matters a lot.
SP: Charlie likes narrow q-factor and I like wide, because I supinate. But they’ve got this thing set. You don’t get a choice.
CC: We set some of the standards. We set the 135 standard. Ritchey and Fisher, their bikes were all 125, with what the industry had back then.
SP: Then we pushed 140 but the industry never made it to that. Remember we had 140 on our [WTB] Phoenix and stuff? That fork that I just made here, it’s a 118. It’s for a big guy. I made it for tandems...
CC: And that’s another thing, they still have 100mm spacing in the front, but they’re packing a disc brake in there now. So again. So they shove it over and make a funky front wheel. It’s pathetic really.
These mountain bikes here, are all 145. That’s been worked out on paper so you get a really good chainline. And we’ve gone to the nth degree to get the q’s right.
As a framebuilder, Cunningham was famous for his light-weight aluminum framesets. Here he’s talking about working with the aluminum to make it both strong and light. Cunningham’s vintage bikes are stored in a basement, reached by climbing down a ladder. He has a heat-treating kiln in the backyard behind his workshop.
CC: Secret processes, I’ve come up with a bunch of secret stuff that makes [aluminum] last longer.
SP: He has a heat-treating facility up in the backyard here.
CC: Jackie [Phelan] raced and trained on her bike for seven years, she won nationals on it, and it’s still going strong. They don’t have to be replaced.
SP: If you build them correctly.
CC: That’s true of all materials, really. If you build them right, you can make them last.
Potts and Cunningham met in 1979, and in subsequent years, they collaborated on numerous components. They sold some products under their own names, and licensed others of their creations to companies such as SunTour and Specialized.
CC: We would make parts and go for a ride to try them out.
SP: We should tell her about the saddles. You know how we developed saddles? I made three wooden saddle blanks. I handed one to me, one to Charlie, and one to Mark [Slate] and we carved them, and we rode on wooden saddles. And guess what, the shape is the most important thing.
CC: If you can get the shape where it feels pretty comfortable, then you add padding.
SP: Our first saddle was the Specialized Prolong which turned out to be one of the favorite saddles of all time. And our second was the [WTB] SST 98, which is still the favorite for most people.
CC: That’s still my favorite saddle. I can’t live without it.
SP: But we struggled with that. I rode literally on a wooden saddle for months. On wood. We used to ride a lot together. Now we just work.
In 1983, Potts and Cunningham founded WTB. It happened mostly by accident. In the process of building their own bikes, they shared the work of building components. Soon other framebuilders wanted to buy the hubs and brakesets and other bits and pieces that came out of Potts’ and Cunningham’s workshops.
When I went to visit Potts, he drove me out to the farmlands on the eastern side of Tomales Bay. On a deserted road bounded with barbed wire fences, the deep green grasses dotted with wildflowers bending in the onshore breezes, Potts dropped me off with my bike and a hand-drawn map.
SP: I dropped Jen off at Chileno Valley and she rode back.
CC: Right on. It’s important to ride your bike when you go places. It just puts a balance on things.
It’s so easy with the industry where it is, kind of in that world, it tends to suck you in and get you away from the thing that got you started. Which is the bike.
SP: And that’s what happened to us when we were trying to run WTB. It took us so far away from what we really loved to do.
CC: It really did. Over the years, it morphed into this increasingly corporate life where we were behind a desk all day. I just love building things.
SP: Quite frankly, we were miserable. I was happy in the shop. I remember everyone had a computer. There were 30 people and 29 computers.
And the only one who didn’t have a computer was me. You know, they’re going this email thing is great, and I’m like, just write a frickin’ letter or pick up a phone. I don’t need no stinkin’ computer.
C: If we’re touching metal, we’re happy. I honestly think, computers are a super awesome powerful tool, and you gotta use them, but I’m only good for maybe 20 minutes before I’ve had enough. I gotta get away and do something.
SP: I’m the same way. You know, Charlie, I got a smartphone, so now I don’t even need to go down. I just look at it, and eh, I don’t need to do anything. Oh, guess what? Let’s see what we got here... [checking new email]
C: This is pretty advanced Steve, you’re way ahead of me. You’re going to be one of those people walking around looking at your little thing.
SP: This is my son, so... [Potts pokes at his phone, clicking the new email.]
CC: Somehow the bike puts balance in it. It makes it so you can do that stuff. There’s no question that that’s where the good stuff happens.
SP: What it is now Charlie, is that I have to deal with 50 or 60 emails a day. So I just stay up in the shop with my thermos of tea and I just keep going. I’m getting more done now.
C: I don’t have that many emails. I have a rarified audience and I want to keep it that way.
SP: This is Charlie in his phone message: I’m here, but I may not pick up the phone. If I like you, I will.
C: No, I’m happy. I could have a lot more business. But I don’t want more. It’s just the right amount and it’s the right people. They’re really good people.
One of Cunningham’s early innovations was the “roller-cam” brake. The first NORBA national championship was held in 1983 in Santa Barbara in the kind of rainstorm only a California El Niño can bring. Racing through the deep mud, most riders quickly wore through their brake pads. Ibis owner Scot Nichol raced that day on a bike equipped with Cunningham roller-cams and despite the mud, his bike still stopped on command.
CC: I’ve been designing brakes since the get-go. The first mountain bike I made a special brake for it. That design has continued to evolve since that day. It’s kinda of reached its pinnacle with the lever length. I think three or four people have them now. I’m not selling them to anyone and everyone.
Discs are plenty powerful but they’re really lacking in control and modularity. They’re dangerous, really.
SP: They store energy, then they get to the point where they can’t store any more energy, and it gets into the braking, and then it’s abrupt.
CC: I find it really hard to ride really challenging terrain with them where you’re not going particularly fast, but you’re really having to control your contact patches. You see a lot of skid marks out there.
[Cantilevers] and V-brakes, they’re better than discs, but they’re still really bad, because of how they’re mounted. It’s based on the original design. The arm design hasn’t changed much, the mounting hasn’t changed at all, really.
In fact, I can show you the original mountain bike down there with [rollercams]. The linkage has evolved over the years. If you ride this thing, you think, how in the world could anyone use anything else? I feel like I’m riding in heaven almost. I get on the latest best disc brakes, they’re great but they’re just...
SP: Charlie is a human CNC machine.
CC: No CNC here. I do all this stuff by hand. I worked out really efficient processes for doing it. I can make parts per bike. I design the brakes for each bike. And they’re different. They’re all made by hand. They’re not machine-made.
Nobody does this. It’s all machine done now. The problem is when you’re making parts with a CNC machine, you have to sell quantities. It takes a lot of money to program the things, so you just don’t see truly custom parts coming out of CNC shops.
SP: That’s what called a single-leverage brake [V-Brakes]. It’s the leverage over where the brake arm is mounted. These [roller-cams] are compound leverage brakes, you’re actually compounding the leverage through mechanical means.
CC: I have to say, a V-Brake is actually a good brake. It’s just poor mounting. The mounting standard goes way back to the turn of the previous century. It was put on all these bikes. It has really great mud clearance, but it was designed for a different kind of beast entirely. It wasn’t changed for mountain bikes.
It was the standard cantilever mount. It’s just got so many things wrong with it. It’s cantilevered way off the frame, so the pivot bushings are far from the tube so it bends the tube and twists the tube.
And then it’s way down from the brace on the seatstays so it’s spreading them too. It’s like taking a good brake and putting a big spring in between it. It kind of loads up, it loads and unloads slowly so you just don’t get this accuracy.
Cunningham picks up a box with jars of tiny, hand-machined small parts.
These are just tons of super carefully made parts for the brakes. ... All these things are all hand-made bits and pieces.
Cunningham’s workshop is packed tightly with machining tools, some of them given to him by Potts. They showed me around.
SP: This is the same tool that I have.
CC: I was using this yesterday.
SP: I gave this thing to Charlie. It’s a really neat little machine, this Craftsman.
CC: It’s a milling machine. It has a horizontal shaft instead of a vertical. Which is not as versatile, but it does certain things better.
If you can think of it, you can make it here. There’s tons of tubing stored under the house. Bandsaws in the back. Heat-treating equipment outside.
And the reason you see spiderwebs and leaves everywhere is that the roof passively ventilates. There’s air gap. In the summer time when it gets really hot in here, it pulls hot air up and cools. But that means spiders and leaves can come in. Mr. Spider will be helping me out.
Over here is just tons of stuff like WTB hub tools and servicing parts. Brake arms, brake pads. And all my frame-building tools. There’s just so much stuff packed in here.
As long as I’m using it fairly regularly, I mostly know where it is. I wish I had more space, but I don’t so I just have to make it work.
These are neat little machines. [Pointing toward another corner of the shop.] These are like 1925 vintage, but they’re good.
SP: This right here is a six-draw chuck. These are extremely expensive and very accurate. That’s probably a $1200 chuck.
CC: I had this whole machine competely reground. And I’ve got a ten-inch six-draw for my other machine.
SP: It is really cool. There’s a lot going on here.
I’m shooting photos of the workshop and Cunningham stops, ever curious, intrigued by my camera.
CC: How many megapixels is that?
SP: A gazillion.
CC: Some of those cameras they have on the moon rovers are like 150 thousand megapixels or something. And then they can zoom in and actually look at pebbles on it.
SP: Do you need a screw or washer? [Pointing toward a shelf of open bins.]
CC: I’m thinking of making... I just got some new clipless pedals from Shimano for my new road bike. I finished this road bike in here, by the way. People always want to know how much their bikes weigh. It’s light! It’s light enough.
I noticed it when I had the cleat mounted so I get the shoe as close to the spindle as possible, I’m still about a centimeter from the crank. I’m thinking of making some new pedal spindles to bring it in a little bit.
I’m going to do that when I get a little time.
SP: There’s plenty going on here.
Cunningham points to one of his vintage bikes, leaning against a wall in the workshop.
CC: This has a magnesium stem. I think this was built in like 1983 or something.
SP: It’s a cool bike.
SP: We’ve made millions for a lot of people. But you know what? I’ll be honest, I’m happy.
CC: I am too. We contributed to the mountain bike and we made it a better thing.