It has been a long time coming, but the Atlantis is finally stable with a front-load. It is a story that dates back to June 2007; when descending Idaho’s Bitteroot Mountains, the Atlantis went into an frightening speed wobble.

Actually, my beef with the Atlantis began well before that. The waning of my love affair coincided with a decision to carry a pay-load on the front of the bike so I could pull-off layers or put on a rain jacket while riding. It was then I discovered this otherwise awesome touring machine was flawed. It was not designed to carry a load up front. In doing so, I had destabilized it.

For the most part, the condition was more of an annoyance than a danger. But that descent in the Bitterroots pushed me over the edge. I made two decisions on that ride. First, I would re-rake or replace the front fork. Second, I would build a new bike, one designed specifically for randonneur events. In the past year, I’ve made good on both of these promises.

I began by working with custom frame builder, Tony Pereira during the winter of 2007. Tony re-raked the original fork. But with the cantilever studs already brazed in place, the process was constrained. He was able to achieve a trail measurement of 49, when we knew 40 would be needed to stabilize it.

We mounted the altered fork and tested it. The improvement made by the 11 mm reduction in trail was noticeable, but far from perfect. By over-steering with my bottom, I was able to keep the bike rolling in a straight line for short periods of time, but not long enough to remove a jacket.

What you can’t see: 40mm fork trail. What you can see: braze-ons hold wiring in place. Wish I’d thought to include two more for the Polar speed monitor.

It was clear that the solution would require a custom fork with the proper trail measure. Tony set-out to make one in the spring of this year and he delivered it in early summer. But like so many projects, it sat on my workbench; preparing for the Rocky Mountain 1200 took all of my attention. What bandwidth I did have was consumed with putting the finishing touches on “T-Rex” – my new, Titanium rando bike, designed by Steve Rex.

Now, with the brevet-riding season behind me, I turned my attention again to the Atlantis. Autumn finally brought hot, dry days to the Willamette Valley, so hot, in fact, that a ride to the cooler, Oregon Coast seemed like a great way to test the new fork. The 102-mile route features three sustained climbs of 30 to about 75-minutes in duration. Road conditions range from city streets in metro Portland, to smooth asphalt highways in the Wine Country, to twisty descents on chip-seal in the Coast Range. There are gravel back-roads in rural Tillamook State Forest, and hellacious potholes north of Cape Lookout along Netarts Bay.

It was 50 degrees at 6:30am when I rolled out of my driveway. I was wearing all the clothes I had with me. I expected to make the pass on the Coast Range by 11am. By then, it would be 80 degrees or hotter, and all those layers would in my Berthoud front-bag.

But at this moment, the main compartment was mostly empty, except for the food I carried: a bar, a baggie filled with Perpetuem, a 6-ounce flask of Hammer gel. Also inside were my iPod, wallet, and camera. In the front pouch I carried a spare tire, patch kit and tire iron; a multi-tool, a few spokes, and a rag. In one of the side pouches I had a first-aid kit.  The entire bag and its contents weighed maybe five pounds by the time my clothing was in it.

The morning was so beautiful that I became completely absorbed by it and I completely forgot about testing the fork. I rode through the farmlands toward the Tualatin Mountains, listening to Pat Metheny on the iPod. Then, as I began the first climb up to Chehalem Pass, I noticed two roadies were stalking me. I had seen these guys back at a café on their carbon jobs. I imagined them saying, “Hey, let’s reel-in that nerd on the touring bike …  the one with the fenders … we’ll smoke him and leave him for road kill.”

I was in the first curve when I saw them gaining on me in my rear-view mirror, so I kicked-it up a notch, just south of my lactate threshold. And I held it there – 150 beats per minute. Let’s see what kind of shape these dudes are in, I thought.

Five minutes into the climb … they are still there, but they’re not gaining. Ten minutes … they are still there … but wait, are they slipping?

Fifteen minutes in … I see the first stair-step on the way to the pass. I am getting hot and without thinking, I sit up and let go of the bars. I tear off my vest and my arm-warmers and stuff them in the front-bag. The Atlantis tracked ahead like an arrow. I look in the mirror. I can’t see them below that last step in the grade. I put the hammer down until the HRM reads 150 beats per minute. Got a Joe Satriani sound-track on the iPod for this steady-state interval.

As I climb to the point where I can see down the mountain, I notice that they’ve eased off. But I don’t – I just keep it level until I reach the pass, and then glide down the other side. The descent is steep and twisting, and the Atlantis is stable – not T-Rex stable; that is something altogether different. But the improvement is marked.

No hands at 39 clicks. That’s roughly 24 miles per hour for the rest of us.

I tested its stability again many times on the ride through the Coast Range. I rode it no hands at speeds between 15 KPH and 44 KPH for extended periods of time. Only once did I detect the remnants of speed wobble. It was a mild oscillation centered around the head-tube. I was able to quell it by placing my knee on the top tube. I later tried to reproduce it, but I couldn’t.

On the whole I am very pleased with the effect the new fork has had on the ride. I consider the problem solved, and well worth the $250 I paid Tony to build and paint the custom fork.

Would I recommend the fix to other Atlantis owners?

I have received numerous emails from riders who say they have experienced the same issue. To them, I would say, yes, re-raking the fork appears to have alleviated the symptoms.

But to Grant Petersen, I must ask, isn’t it time you go after the root cause, and offer your customers who prefer a front load, a Rivendell-built fork with a lower fork trail measure?

Tags: Atlantis, Fork trail, Rivendell, Speed wobble

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