Random musings from ptw
Despite the conditions, Neil managed to stay on her bike this year, and earned a Kona slot (also took the Vegas slot). Hopefully, she will publish a race report soon.
But I thought I’d give a bike tech report… this being a very technical course.
I had swapped in a 11-28 cassette for the hills (after discovering that the weld on here rear Zipp had failed,
I swapped the cassette onto her training wheel), and replaced her chain, because I needed a couple more links to get over that huge cog. I used a SRAM 1090 chain. Had to back off the b-screw one turn too, because of that 28 cog.
We did a few test rides before sending her bike off to TriBike Transport, and everything seemed fine.
But when we got to St. Croix and took a practice ride out on the East End,
she had a lot of trouble with her front derailleur. Seemed like shifting onto the big ring was just not picking up, but then often the chain would catch, but not drop in, and then about half way around slip off to the outside. I tried adjusting the high limit, eventually down to 1/16 turns, back and forth, test/adjust/test, and still could not find a setting where she could both shift and also not have the chain go too far and fall off to the outside. (We do appreciate the little pins on the Q-Ring that let you trim the shifter and get the chain back on without stopping.)
Tried the LBS, who seemed quite capable, but they were not able to do any better than I. Things shifted ok on the repair stand, but not on the road, and were particularly bad under load. I consulted “The Google” and found a number of people who had trouble with the SRAM Red derailleur and Q-Ring combination, especially under load. The most common fixes seemed to be:
- Follow the Rotor instructions to the letter to make sure your derailleur is adjusted correctly
- Replace your chain
- Replace your derailleur
I also thought there was a very slim possibility that having different offsets for the inner and outer Q-ring might mean that the chain was trying to pick up in the wrong spot. We had advanced the inner ring to #3 on the theory it better matched her climbing position.
What I tried:
- Putting the inner ring back to the #4 offset, so it matched the outer. Didn’t seem to change things.
- Very carefully following the Rotor instructions on aligning the derailleur. Didn’t seem to change things.
Neil was very nervous about riding this course again, the last thing she needed was for her shifting to be twitchy, so I bit the bullet and bought a new derailleur (knowing that my Ultegra seemed to work fine, and has quite a different profile than the SRAM, I thought I would try that, but we were only able to locate a 105 in St. Croix). I also put on a new chain, mostly because I have not figured out how to install a Shimano derailleur without breaking the chain, and despite the SRAM chain being brand new, I worried about re-using the quick-link. I’ve done it in a pinch, but didn’t want to risk it in what was a very important race to Neil. The only chain I could find was a Shimano DuraAce. Luckily I had my chain tool in my tool bag.
With the new chain and derailleur installed and adjusted, it seemed like the shifting was better on my repair stand (the overhanging kitchen island), so we took it out for a test ride. Neil reported that the shifting was much improved, which was good, because at that point, I was going to be out of ideas.
On race day, Neil discovered just how improved the shifting was, as she got to ride the last 19 miles of the course for the first time and discovered how technical it was. It all worked out in the end — after being 4 minutes back out of the water, she gained 10 minutes on the bike, and although 3rd place gained 2 minutes on her on the run, she widened the gap on 2nd by another 5 minutes, and secured her Las Vegas and Kona slots.
Happy days, but only after a lot of gnashing of gears. :)
I wonder if farm-raised vegetables taste as bad as farm-raised fish, but we’ve just been eating them so long we don’t know any better?