Kuma601
12-06-2007, 06:39 PM
Today's plan was to put the CF forks onto the Atala. For them most part, pre-fit was smooth. The lower bearing race wouldn't slide down the steerer tube to seat properly and was about .6mm oversized, I took that down by hand. During the fitting, I managed to crack/break the lower dust seal...I wasn't happy on a part 17 years old and probably not findable. I did have a Campy Record on hand anticipating problems. Murphy had his way and the lower race for the Campy has an even smaller diameter and I'm not going to take any more off the fork steerer tube even as small amount it is.
The Atala steerer tube measures out to be 26.40mm for the lower bearing race. The Nashbar CF fork was 26.46mm there. The lower bearing race for the Campy Record is 26.33mm. Ah the joys of mass tolerances. :( Since the dust seal on the Shimano is self contained and held in place, I decided to re-use it anyhow. Fitted the fork, cut the steerer and thought I was on the home stretch.
The thickness of the fork, the brake bolt was about 6mm too short. No big deal, I'll get a longer sleeve. So I let the brake dangle and inserted the 3TTT quill stem. UGH...I got about 6.7 cm of insertion and it just stopped dead. It will clamp but for my ride preferences, I want another 1.9cm of insertion.
Looking into the tube, I cannot discern a change. I lightly chamfered the quill stem at the flange opening since it does flare a bit. That didn't work. :( I tried to test fit a Nitto and it too stops right at the same point.
(Edit) Ironically if I chose to go threadless, this wouldn't be an issue but I want to have some resemblance of the original threaded steerer assembly.
While I cannot measure it, the inside diameter tapers/becomes thicker 6.7mm down. My rough guess is it goes from 22.2X to about 21mm. So short of boring out that bit more I won't be able to get the quill stem down any further. :( Structurally, I dunno if it is safe to bore down 2 cm more. :| Oh well, failed project. The forks did look kinda nice and it did lighten the front end a handful of grams.
The Atala steerer tube measures out to be 26.40mm for the lower bearing race. The Nashbar CF fork was 26.46mm there. The lower bearing race for the Campy Record is 26.33mm. Ah the joys of mass tolerances. :( Since the dust seal on the Shimano is self contained and held in place, I decided to re-use it anyhow. Fitted the fork, cut the steerer and thought I was on the home stretch.
The thickness of the fork, the brake bolt was about 6mm too short. No big deal, I'll get a longer sleeve. So I let the brake dangle and inserted the 3TTT quill stem. UGH...I got about 6.7 cm of insertion and it just stopped dead. It will clamp but for my ride preferences, I want another 1.9cm of insertion.
Looking into the tube, I cannot discern a change. I lightly chamfered the quill stem at the flange opening since it does flare a bit. That didn't work. :( I tried to test fit a Nitto and it too stops right at the same point.
(Edit) Ironically if I chose to go threadless, this wouldn't be an issue but I want to have some resemblance of the original threaded steerer assembly.
While I cannot measure it, the inside diameter tapers/becomes thicker 6.7mm down. My rough guess is it goes from 22.2X to about 21mm. So short of boring out that bit more I won't be able to get the quill stem down any further. :( Structurally, I dunno if it is safe to bore down 2 cm more. :| Oh well, failed project. The forks did look kinda nice and it did lighten the front end a handful of grams.