Rides
               

The following is a Schwinn Super LeTour, which has been converted to a fixed gear. I chose it, among others, because it had a 4130 Chrome Moly Frame and is therefore propably stiffer. As it works out, it is nice and stiff and the finished bike really works very well, but the 59cm frame is just not long enough for my reach, so I will be replacing it with the blue 68 1/2cm Bridgestone found further down the page


The Schwinn has been lightened of all of its cable routing braze-ons, and minimized to just was called for on a fixed gear bike. I also replaced the rear brake bridge with a similar tube, minus the brake mounting hole.


Rear eyelets, as well, came off in an effort to visually simplify the whole bike.


Respacing the rear wheel was something new for me, and kind of fun. What I did was to remove the 5/8" spacer found outboard of the right bearing, and replace it with a pair of 5/16" spacers (one on either side of the hub), to make the bearing spacing on the axle symetrical. This moved the whole wheel to the right by 5/16". The next step was to move the rim back to the left, to get it back on the center line of the bike. To do this, I simply loosened the right side spokes each 3 full turns and took up the slack on the left side. The photo does not show it very well, but the result is quite satisfactory. The 18T fixed cog simply screws onto the rear freewheel threads and is held in place with a bottom bracket lockring and an application of Locktite Blue (medium strength).


There is a challenge in getting the chain allignment sorted out. The large chainring mounts too far outboard to line up with the rear wheel. So, I have taken a couple of steps to move it inward. Subsequent to these photos, I replaced the crankset with a stiffer one where the right crank has a cast spider and a separate set of chainrings. I mounted the large 52T chainring on the inboard side of the spider, and reversed the bottom bracket spindle, putting the "long end" on the left side of the bike. This works out just fine. The large chainring is very close to the recess in the right chainstay, but clears it with "racing tolerance".


The result of this test project has been a success, and like many tests, it produced unexpected results. As a result, the next fixed gear will be a little more "purpose built". The rims are narrower, 27" x 1" instead of 27"x 1 1/8", the frame is larger to fit me better, the sprockets will be smaller. The combination of 52 x 18 produces 78 "gear inches". By generating a chart of sprocket sizes and ratios, I have found that 77 gear inches can be achieved by using the 40T front chainring and a 14T rear cog. I will try that on the Bridgstone (BS). A slightly lower gear would be OK. I am still experimenting with overall ratios, and the smaller front chainring will have a different visual effect, as well as being a bit lighter. It is another test.


I like the BS frame size and tubing, but not the looks of the seat stays, so I have changed them a bit. The offending element is the way they look when brazed to the side of the seat lug. I just think it looks "added on". I removed them and replaced them one at a time, leaving an axle in place, to help maintain rear frame alignment during the process. This, again, was an experiment, to see if the rear end would go crooked when i cut out a seat stay, or would it stay put. I clamped in a spare rear axle and then cut the brake bridge, and the top of the right seat stay. It all seemed to stay put very well, so I heated and removed the stay from the rear drop out. Then I fitted a new thin-walled 1/2" mild-steel tube to the place and brazed it in place. Doing the same to the left stay, after the right stay had been brazed in place, with the axle still clamped tightly in place. I preferred the visually tighter look of the "fastback" style of seat stay, so that is the effect I have tried to achieve. After the seat stays were both in place, I fashioned a short bridge to brace the rear triangle, replacing the former brake bridge. It will not have a mounting hole.



This is the first step in the process. There will be more to come. The hubs and rims look good, but the spokes are major ugly! Something has to give there. My hope is to have it totally shaved, as the orange bike, except for the bottle cage mounts on the downtube, and painted John Deere green and yellow colors. It is a lugged frame and should detail nicely.


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