djcwardog
09-25-2006, 02:46 PM
...based on recent forays into bike assembly/fitting:
1) Cutting seatposts - An alloy Ritchey (for the Paramount) and a carbon EC-70 (for the Ottrott)... Okay to take the measurement off the stock (and very long) post from the end up to the min insertion line (seems ~4" or so) and then run that up the post to, say, an inch below max height needed? In other words, fit for max height, add an inch down, place a new mark for min insertion, then measure down the same distance as from the stock min insertion line to the stock end - and cut? This would drop off 5" or 6" on these posts, save a little weight, and make it easier to adjust the posts without so much jammed into the seat tube...
2) Removing the top headset donut on a Reynolds Ouzo Pro fork (in its Serotta F2 guise) - This involves the Chris King 1 1/8" headset on my Ottrott. Wanting to slide the fork out of the frame to cut excess carbon steerer tube from the end, having already mounted a stem plus 40mm of spacers below it - max spacer height allowed, correct? - I encounter considerable resistance from the O-ring sealed top donut on the headset. That donut should just slide up and down the steerer tube. Fully aware of the properties of carbon fiber and its lack of ability to tolerate direct impact compression loading (i.e. a hammer on the end of a tube!) I end up carefully and softly tapping it down and out with a crown race driver and appropriate collet to fully engage yet avoid damaging the carbon. I make the steerer tube cut (with an excellent golf-shaft cutter intended for steel or carbon golf shafts - another hobby of mine is to assemble golf clubs) and reassemble. The donut fights sliding down the tube as well, even with a greased O-ring. I end up using the CR driver (again!) but with a different collet to engage the donut itself to carefully snug up the assembly, then tighten the expander nut - and the assembly refuses to snug up that last minute bit of slop before the nut torque goes way up and I stop. I then loosen it up, pull off the stem and spacers, and give a few more love-taps with the CR driver, again, directly on the headset donut, while I put weight on the now-assembled wheel and fork by straddling the frame. The setting holds as I reassemble spacers and stem, all slop goes away. I tighten the nut at the top, then the stem, and the steeering action is superb. What the heck? I thought threadless headsets were supposed to offer very minute and very precise adjustment of the bearing pre-load. Hard to believe that I have to carefully apply "special tools" to get a zero-lash preload and no rattle in the headset... When working on cars, using "special tools" (like a hammer...) is attributed to "Bubba." This is not always bad if it gets you back on the road, but otherwise, it can be the sign of a knowledge deficiency...! Do I chalk this up to gaining some more bike mechanic experience and ride happy (the Ottrott), or should I acknowledge a "knowledge deficiency" and be alarmed.. and look out for something...? In any event, I see no impact markings or fraying on the end of the carbon tube, my fork looks and works great and there is no excess tube (or spacer) above the stem.
3) Where can I find a classic-looking quill stem for a 1" steerer tube - that accepts oversize 31.8mm bars and is parallel to the ground (i.e 73 degrees)? Right now on the Paramount I am using a faux-threadless stem (quilled shaft (only) that accepts a 1 1/8" threadless stem) so that I can use the same range of Ritchey 4-axis stems I have collected to trial-fit both of my bikes.
1) Cutting seatposts - An alloy Ritchey (for the Paramount) and a carbon EC-70 (for the Ottrott)... Okay to take the measurement off the stock (and very long) post from the end up to the min insertion line (seems ~4" or so) and then run that up the post to, say, an inch below max height needed? In other words, fit for max height, add an inch down, place a new mark for min insertion, then measure down the same distance as from the stock min insertion line to the stock end - and cut? This would drop off 5" or 6" on these posts, save a little weight, and make it easier to adjust the posts without so much jammed into the seat tube...
2) Removing the top headset donut on a Reynolds Ouzo Pro fork (in its Serotta F2 guise) - This involves the Chris King 1 1/8" headset on my Ottrott. Wanting to slide the fork out of the frame to cut excess carbon steerer tube from the end, having already mounted a stem plus 40mm of spacers below it - max spacer height allowed, correct? - I encounter considerable resistance from the O-ring sealed top donut on the headset. That donut should just slide up and down the steerer tube. Fully aware of the properties of carbon fiber and its lack of ability to tolerate direct impact compression loading (i.e. a hammer on the end of a tube!) I end up carefully and softly tapping it down and out with a crown race driver and appropriate collet to fully engage yet avoid damaging the carbon. I make the steerer tube cut (with an excellent golf-shaft cutter intended for steel or carbon golf shafts - another hobby of mine is to assemble golf clubs) and reassemble. The donut fights sliding down the tube as well, even with a greased O-ring. I end up using the CR driver (again!) but with a different collet to engage the donut itself to carefully snug up the assembly, then tighten the expander nut - and the assembly refuses to snug up that last minute bit of slop before the nut torque goes way up and I stop. I then loosen it up, pull off the stem and spacers, and give a few more love-taps with the CR driver, again, directly on the headset donut, while I put weight on the now-assembled wheel and fork by straddling the frame. The setting holds as I reassemble spacers and stem, all slop goes away. I tighten the nut at the top, then the stem, and the steeering action is superb. What the heck? I thought threadless headsets were supposed to offer very minute and very precise adjustment of the bearing pre-load. Hard to believe that I have to carefully apply "special tools" to get a zero-lash preload and no rattle in the headset... When working on cars, using "special tools" (like a hammer...) is attributed to "Bubba." This is not always bad if it gets you back on the road, but otherwise, it can be the sign of a knowledge deficiency...! Do I chalk this up to gaining some more bike mechanic experience and ride happy (the Ottrott), or should I acknowledge a "knowledge deficiency" and be alarmed.. and look out for something...? In any event, I see no impact markings or fraying on the end of the carbon tube, my fork looks and works great and there is no excess tube (or spacer) above the stem.
3) Where can I find a classic-looking quill stem for a 1" steerer tube - that accepts oversize 31.8mm bars and is parallel to the ground (i.e 73 degrees)? Right now on the Paramount I am using a faux-threadless stem (quilled shaft (only) that accepts a 1 1/8" threadless stem) so that I can use the same range of Ritchey 4-axis stems I have collected to trial-fit both of my bikes.