Andrea’s road disc
A couple of years ago I built a bike for Jeffrey – he visited to pick it up and was one of the first guests to stay at Velo B&B. This time around I did a custom build for his wife, Andrea, and they were both able to come and stay to collect it.
Andrea didn’t have a fit she was totally happy with, so she worked with a local fitter, and I then designed her bike around those numbers. She decided to go with disc brakes, and after reviewing the specs I suggested a custom steel fork as being a better fit with the frame than a carbon fork – all the carbon road disc forks have tapered steerers, requiring a bigger/heavier headtube and headset. With a custom fork I can stick with an 1-1/8″ steerer and it also gives a better aesthetic with the rest of the frame. Additionally I was able to adjust the rake for the fork, which helped me maintain good handling whilst eliminating toe overlap.
The other consideration on this build was to allow for a future upgrade to wireless shifting, once that comes along. To meet this criteria, I came up with a minimal bolt on sleeve for the bottom of the headtube, that gives removable gear cable stops. The BB cable guide also bolts on, as does the cable stop on the chainstay. So all reference to cables are easily removed when the time comes.
The hydraulic hoses all run internally – the rear one goes from downtube to seattube to chainstay, since there isn’t room inside the BB shell for it. The seatpost is a Syntace Hi-Flex – to allow it maximum length to do the passive suspension flexing the seattube is as short as possible where it meets the toptube.
Total weight complete with pedals is just over 17lbs. Eric at Colorworks once again did a great job to match the Industry 9 orange hubs, and Andrea came up with a neat alternative to the usual ‘E’ for the headtube.
That HT cable guide is so neat!
Quick question, any worries about corrosion for the fork? Is there some kind of drain hole to allow water to run out at the bottom? Or some kind of housing guide that runs through the leg itself? Or just a simple case of leaving it upside down once and a while?
A good question – fork is treated with Boeshield on the inside, and I’ve suggested sealing around the hose at the top with silicon if it is ridden in the rain much.
thanks,
Rob.
Hi Rob, First of all, love the design and attention to detail on the bike. One question, I noticed that the seat stays, besides having a very elegant shape, look very thin. Is there a special reason for?
Thanks,
Raymond
Hi Raymond, I select tubing based on the loads that part of the structure is intended to support. For the rear end of a road frame, the chainstays, once triangulated across the rear hub axle, provide all the lateral stiffness between the bottom bracket and hub. Thus the seatstays are just acting as a prop, and as such are only loaded in compression. The failure mode for a compressive load in tubing is buckling – and with the intrinsic high stiffness of steel, even the 3/8″ tubing I use for the stays is operating way below its buckling load. So the stays may appear small, but they are sill overbuilt!
thanks, Rob.