INTO THE RIDE #38
Adventures of Scrapper Bikes
AND THE ROAD BRAKE ADAPTOR
by Randy Schlitter
I love my scrapper bikes. Over this winter I have built up a whole fleet, ranging from long wheelbase bents, to CF’s. They are a charming bunch of machines; all happy to be saved from a life of just hanging in the parts loft as discarded, dismembered bikes. They actually seem happy to be assembled! I can tell this when I ride one. There is just something special about a bike that was pulled together from spare parts, overruns, prototype frames and scraps.
I use the scrapper bikes for tests. Before launching the Formula 26 we needed to test the idea of converting a normal V2 into a dual 26. I scrounged around in the loft and found a V2 XL frame that was damaged in shipping. The right chain and seat stay were bent in about half inch. After a bit of tugging the rear wheel went into the dropouts without a fight, and lined up on center frame. This was one frame wanting to be ridden. (scrapper bikes are like that, if you hadn’t guessed).
This V2 was rescued from the parts loft, and is a combination of parts collected over several years
The first order of business after realignment was to chop off .7” of the head tube. This was a bit tricky over the other Formula, since the steel frame head tube has a smaller OD. Clamping blocks made from wood scraps did the job, and then a little time with a reamer and the cut was true.
With the headset pressed in perfectly aligned, the rest was down hill till I got to the front brake. The used front wheel was not disc brake compatible, and the canti brakes hit the crank. Bolting a road brake to the fork through the original mounting hole would require an unheard-of brake reach. The solution was to fabricate an adaptor from .75” round stock. I started by drilling the holes through the stock prior to turning down the stock. I then test fitted the adaptor as I machined down the O.D. since the fork I.D. varies. The adaptor needed to fit tight without any movement.
I tested several road brakes for fit to the rim and all seemed within adjustment range. The Tektro 432’s ended up on the bike; it is a sturdy, good stopping brake.
Use 6061-T6 .75” round to make a road brake adaptor. A Hollow tube of very thick wall will also work, but I prefer the solidness of the round stock.
The Tektro brake installed.
Drill the fork and adaptor to accept the retainer nuts.
The Tektro brake or just about any road brake will tuck neatly within the profile of the fork for no worry about interfering with the crank.
If the unused canti mounts bother you remove them, but first loosen the Loctite by heating to hot-to-touch with a common hair dryer. This is an important step; you will only strip the mounts if not preheated. Remove while still warm.
On the very next nice day I decided to get to know my new scrapper V2 dual 26”. I set up a special Zephyr seat, 3-Way Chopper bars, and Primo Comet tires. I was impressed with the initial ride. Being an XL frame I was well forward on the rail, and offered up a nice cushy ride. At first I was not happy with the placement of the bars. I wanted a combination of max lean back on the seat, but real low end maneuvering. It turns out running them pretty flat on the handgrips, but more vertical overall worked best.
Starting out with the bottom of the bars as high as possible on the stem was not working. If you looked close the tips of my toes were nowhere near hitting. Lowering the bar and turning the grips out flatter and tilting the bar up greatly enhanced the handling. Again, the key is having the handgrips fairly flat, and the bar more vertical to omit tiller. My knees clear, so tight turns are fun, and the handling at near 0 MPH is fine, no gainful wheel flop. The flatter wide bar setting takes it right out. I cannot overstate how important it is to take the time to set the bars. The difference in handling is outstanding and well worth the time invested.
This setting works to stabilize and clear the knees, and allows for very tight turns; spinning about in less than a lane width is child’s play.
Note the position of the bar is with the handgrips into the U as deep as possible and rotated to 1.5 marks for the outer most.
With the bike tuned in I took advantage of the nice weather and rode a couple of hours. After a few minutes the feel was quite natural and I was having fun. The big wheels are a blast, and with careful tuning of the bar and seat tilt the bike comes alive. Perhaps the most fun aspect of the bar setting was the carefree turning, not a worry about knee engagement. The other charming aspect about the bike was the scrapper nature. This combination of a saved frame, an el-cheapo crank, an odd combo of road and canti-brakes, and a prototype Z-seat all became a well-tuned working entity extending to me a great riding experience. Sometimes the best equipment is second string just anxious to get off the bench and get into the ride. Until next month ride safe and stay into the ride!
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