So you go for the Manly Man (Womanly Woman??) 55 ring!! What is the smallest inner ring that will work? I am thinking a 42 will be fine (13 tooth drop). but want to be sure.
Also, with a 55 ring and a 10 speed cassette can you use big/big so as to avoid a potential dropped chain or just because thats where you end up. Ive never used a 55.
USA Masters National Time Trial looks like its got a screaming 2 ot 3 mile finish. Unless its a headwind a 53x11 “looks” too small. And what the F#@$ is up with Masters TT being only 24k and the day after the road race? Potentially less than 13 hours apart for those with late starts.
55 front should go to a 44 or 42. I’m riding a 44 x 56 and an 11 x 23 for TT races. I ride a 42 x 54 for triathlon with a shorter crank arm as I’m a bit older now.
Thanks guys. Whats the crossovers without the chain hitting the big ring (42x13??) and can you use the 55x23 if need be? Assuming a 11-23 cassette again.
… can you use big/big so as to avoid a potential dropped chain or …
That is going to be an ugly chain line (friction) and likely result in your RD cage being beyond (forward of) vertical…
Yeah-thats what I thought, thanks for confirming.
I’d probably wait for someone to confirm what the course is actually like. According to the Delorme map (which seem to often be wrong), it looks like 22 percent for the last 1/2 mile. If it’s anywhere close to that, pedaling would be a complete waste. For that matter, if you’re legitimately spinning out a 53/11, I think you’d be better off getting into a full tuck rather than pedaling–even at the finish. I’d stick w/the 53.
I did it in Map My Ride (still not that accurate, but usually Conservative on grades) and it looks like 2 to 3% for 3 mile descent. But who knows!!
Remember last year? The first Delorme map made the course look like the hardest road race course ever with these never ending steep hills. My buddy and i were talking about using our road bikes. Turns out guys were averaging 27 to 30+Mph. sadly I was in the 27mph camp, not the 30mph camp.
yeah, I’m not even sure why I bother looking at those things. It also shows a 6-8% descent into the turnaround?? I’m guessing that’s not happening either…
At 3% with a bit of a tailwind, I still think I’d go with the 53 and a butchered cluster (11-28 8 speed) and scrap the small front ring. Call me paranoid, but someone’s going to end up dropping his or her chain–don’t let it be you…
yeah-my buddy and I who did it last year are not that impressed. Sure-same for everyone!! but still. I just started racing when the 7 Springs courses were run, but didnt they learn their lessons with short courses at nats?
or starting in the small ring and having 1 second cost you a podium spot. doh!
judging/guessing from that map, if there are any 6-8% points on that course they’ll be about 50m long.
and chain rings are one place we disagree - i love the 55. at ccc or something hilly i’d probably swap out for an 11-25 in order to avoid repeat of above.
I’ve been using a 55/39 for about a year now with the occassional chain drop. In general it works fine, it just isn’t perfect. I’m planning to switch to a 42.
FWIW, I just did a 16 mile TT this weekend. Out and back, 9 miles out, 7 back. 400’ gentle ascent between the start and turnaround.
Check out my splits: 33:23 to the turnaround at 9 miles! 10:00 for the 7 miles back to the finish. On a 1% descent I averaged 42.6 mph for 7 miles. Highest speed was 48.6 mph at over 120 rpms in the 55x11. Average cadence for the 7 miles was 107 rpm. I never shifted once on the return. My teammate did a 9:00 on the return with a 58x11.
Weather station at the nearby airport recorded wind speed at 31mph gusts to 40mph during race time. Wind direction was perfectly down the course, no crosswind at all. I did the entire course last year in 36:25. 43:23 this year with the wind.
Definitely the most interesting TT I’ve ever done.