Recently I acquired a white Davidson Impulse in 54cm. After searching for quite some time on eBay for various steel frame bikes in the right condition, price, and style I wanted, I settled in on this frame that also came with a fork, headset, and a few extra parts. It was to be a single speed project, not fixie/urban bike for riding around and enjoying the feel of a steel, lugged bike. Steel is a traditional material and although it can be slightly heavier than some of today’s modern carbon fiber, aluminum or titanium, the ride quality is still unmatched. I spent months trying to coordinate parts and gear that would compliment the frame and not break the bank. Since the frame is a little dated and uses standards from a bygone era, things like seat post sizing, threaded headset, etc., all needed to be taken in to account and spec’d accordingly. Since I have a modern Colnago CX-1 race bike, I figured this would be a unique project. When I purchased the frame and fork, it was estimated to be from about 1988-1990 by the seller. It does have some cosmetic scratches (bike patina), but overall was in great shape with no rust or dents and still had the original paint and decals.
Davidson is a frame builder out of the Seattle area, and he still makes great bikes to this day. In fact, a few friends have actually visited his "factory" wedged in the back of a bike shop and marveled at his technique, quality, and style. In any event, I still had a place to go for any research, problems, etc., that I might ever encounter.
Since I was planning to ride this bike and build my strength, having it perfectly vintage wasn’t the intention although keeping to that style of the era was; this was to be a rider’s bike, not a shelf queen. There are a decent amount of hills in my area, so finding the right balance was key for climbing and descending. Soon, older Campy cranks were put on and matched with a 39 tooth (inner ring) that was flipped to line up the rear 16 tooth ring. This was nice and convenient since I didn’t have to use a single speed or track crank, but instead could use what I had on hand. I would start with this gearing since I could use what I had already up front and although the back was 16, using a freewheel hub meant I couldn’t go any smaller. The headset is Campy and I found some Campy aero record levers with white hoods that would work with Campy Chorus brakes. Next came the Cinelli stem and Cinelli bars. The build was looking pretty good, but wheels were needed to be built up to work with the correct offset and spacing and still work with a pair of 32h hard anodized Mavic rims. These were laced up to a Campy record front hub and Surly rear hub for Single Speed with bolt on. I then added a Thompson offset silver seat post; not from the era, but priced well and works great and still within my budget.
John Coleman from Banning’s Bikes in Fullerton got to work on the build and helped with any miscellaneous stuff I might need along the way. John is a good friend of mine and we’ve been known to throw back a few tasty brews in the evenings. For the finishing touches I went with a modern seat, pedals and tires since I knew some miles would be in my future rides. After the final tweaks were done, I hit the road. All I could say was wow. This bike was smooth and the geometry had a nice aggressive feel without being too twitchy or unstable. After putting a couple hundred miles on it in a couple of weeks, I was finding the bikes “sweet” spot and really starting to push the geometry by testing the limits of what the bike was capable of. I started riding the bike with my riding partners who use geared bikes and was quickly surprised how well it held its own. I soon found myself doing 3-4 hour rides and climbing 3000+ ft of elevation. Yeah it was a grunt, but over time the bike gave me a lot of confidence and taught me how to be more efficient and smooth with my riding. Descending is where this bike really shined. Unlike my Colnago, this bike falls in to the turns better and holds a line rock solid- remember I have to be very efficient to keep up with the boys. In fact it does everything better than what I was expecting. It is also very comfortable. My back tends to get a bit sore on my other bikes, but with the Impulse my positioning is great, and is still aggressive. After all, I like to ride hard and race and this thing is no “comfort” geometry- it doesn’t need to be. My project bike that was meant as a weekend, “Sunday” bike was quickly becoming a staple on a few of my outings. Just goes to show that a 20+ year old bike can still hold its own against modern stuff if the quality and design are solid. I did however notice that the back end of the bike wasn’t very stiff laterally, and a bit of research showed that was common for bikes of that era. Of course more modern advancements in steel construction has changed some of that, but it isn’t too bad. Steel bikes from builders like Pegoretti have taken advantage of improvements in steel construction and they’ve been able to make steel bikes lighter, stiffer, and still have the feel most riders covet. But, considering everything, it is pretty nice and frames from builders like Pegoretti can cost you a second mortgage.
Well as the miles kept racking up, I started to notice a few things that weren’t exactly how I wanted. This is common with bikes and there are always a few minor adjustments that hours on the bike will show. First were the bars, brakes and stem. The brake hoods are classic for the era, but I was more interested in performance and comfort. After all, many items on the bike weren't specific to a specific build of the time, and although the frame rides great, isn’t exactly being sought by vintage bike collectors or shown as a museum piece. The brake hoods were just too small and narrow and would cut in to your hands over time. Also, the bars were very deep and the curve rounded off, making positioning of the hood very awkward. No matter how much I rotated them on the bars, they just couldn’t settle in on a good spot for overall comfort and reach when braking. So instead, I went with a set of Cane Creek brake hoods. There is a reason modern brake hoods are so big and ergonomic. Advances in materials and theories have evolved them to shape to the hands better and still maintain low weight, comfort and function.
The bars were still a problem though, but since they were Cinelli from an older era, I was forced to take a look at the stem as well. Cinelli of that era commonly used a bar diameter that limited what stem you could use. Most riders just had to deal with it and use both Cinelli bars and stem together and since Cinelli was so popular in those days, most didn’t really mind. But, those days are gone, and the inconvenience of using a specific system that has gone out of favor has shown some side affects. Another problem was the steering tube and headset. Older bikes used a threaded system that has long been dropped in favor of threadless. Fortunately I was able to find a converter from Profile Designs (pretty cheap, although a bit of weight) that sized up the steering tube and spread out in the headset, so then I could run a modern stem that also worked with a modern handlebar. I found a great 3T aluminum, ergo shaped bar that I liked with a nice aero flat top for more hand positions. This combined with a 3T aluminum stem seemed to be the right choice. A quick ride shortly after confirmed my choices and I enjoyed the overall improvement in comfort and feel.
One last thing that loomed over my head, was the gearing. Although the 39/16 combo worked pretty well for climbing, it soon became apparent that it was just too low for the flats and descents. I kind of expected this to a certain degree, but I found I was just “spinning out” too much in the flats. This would cause me to bounce around a bit more often than I wanted and it was just too low to maintain even a reasonable average speed. I also noticed that most the the bigger climbs I had been doing, although a bit of effort, weren’t unreasonable, and that even with a few more teeth I would be able to handle it. The problem was in the cranks. Since they were an older set of Campy, finding a front gear in the same pattern was proving to be elusive. I was in need of a 42 tooth ring, but that specific piece could only be found from a vintage company that had large minimums when ordering parts. The minimums could be waved if I was willing to pay the extra fee, but this project was more about the passion, not about deadlines or having to rely on it for my rides. Time ticked and the bike starting to sit a bit more. I even considered throwing a full set of gears at it, since the experience of riding a single speed was starting to wear off on me and the problem of locating a 42 tooth gear was still ongoing. This also meant that if I wanted to throw gears at it, I would have to either rebuild the wheels, or find new ones, get a rear derailler, front shifters, etc.; not exactly the easiest transformation or wanted expense.
As chance would have it, a rider from my bike club was looking for a single speed, steel bike and just happened to be almost exactly the same size as me. We set up a meeting and he took it for a spin. He loved it instantly and the bike now has a new home. I explained to him all the issue I had with the front gearing, and what he could expect, but he had a history with single speeds, and was a strong rider, but had yet to really experience a steel ride. He had also heard of Davidson and the bike just happened to be spec’d with items that mirrored a lot of his tastes. I could tell my bike would have a great new home and continue to see many more miles for years to come.
