Ok folks, I have a question for the bike mechanics out there. I have a friend who is trying to convince me to switch my crank to a 54/42, however I am really not sure on the difference besides the number of teeth. Any help would be appreciated.
Why are they saying to do that?
What is your power output, races you’re targeting and cassette range.
they say for more power…?
are you maxing out your current setup? as in cadence of like 100 in 53-11?
comfortable about 150 watts=6 intensity, currently have a few more olympics lined up, and full IM in november. Will the larger crank help me?
cassette is 12/25
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chances are it will hurt you. I would keep your current setup.
a bigger gear allows you to go faster, if you have enough power to do so. If you currently ‘spin out’ with a 53 big gear all of the time, a 54 would help. It should be noted that Fabian Cancellara, the greatest time trialist ever, uses a 53T front gear when it is flat. you are not him.
a bigger inner ring has basically no advantage at all except to make steep climbs or horrible head winds harder than they already are.
ok, thanks. That is what i figured, I will stick with what I got.
I’ll add a caveat that if you find really low cadences to be preferable, you might want to go bigger on the chain rings.
Ok folks, I have a question for the bike mechanics out there. I have a friend who is trying to convince me to switch my crank to a 54/42, however I am really not sure on the difference besides the number of teeth. Any help would be appreciated.
Are you on 650 wheels?
no, 700
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no, 700
Keep your 53/39. I do a lot of TTs and am around 57-58 minutes for a 40k and there has only been one time that I spun out of in my biggest gear 53/11. And that was downhill with a bit of tailwind.
I have a 54T ring I break out when I’m riding/racing in places with long downhills. I have not used it yet this year.
In a 53/12 - 90 RPM will take you to about 31MPH
in a 53/11 at 90 RPM you get to 33.9
in a 54/11 you get 34.5
you can play with ratios and cadences at http://cycleseven.org/bicycle-gear-inch-calculator
Unless you spend significant time over 30MPH - not much reason to get new gearing.
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of course you can get a 54 and keep the 39
which I do because nobody makes a 53T aero chainring anymore
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FSA, Rotor, Vision, Highpath, all make aero 53s. They can be hard to find and pretty spendy though.
Styrrell
I have both set-ups, which I’ll swap depending on courses. Of course you don’t really need a bigger chainring, but I think looking at it from the standpoint of potentially spinning out in your smallest cog is not really the most applicable way to look at it. More realistically, on a flat course, you’ll spend most of the time in the 12-13-14, depending on wind. All else equal, I’d rather be in a bigger ring and the 12 than a smaller ring and the 11 (the other side of this same argument comes up when talking about running a compact 50x36 in front, too), so you can keep a straighter chainline. Of course that’s predicated on being able to maintain your desired cadence in either case. The 42 (or even a 44) just makes for a smaller jump to the big ring for a slightly easier shift, since you don’t need a smaller small ring if there’s no climbing, only for warm up/down and possibly at the very start until you get up to speed.
So how much does having the straighter chainline help? Surely not much, maybe a watt or perhaps even less, I dunno, but what I do know is I can hear the difference in the workstand between having the chain on the 1st or 2nd cog. Not enough to hear while riding of course, but I know it’s there, and you know it’s metal-on-metal contact that’s making the sound so for certain less = better. Most folks don’t bother with having multiple gear combos and that’s fine (I’ll also swap cassettes if there are more/bigger climbs) but neither is it a total waste of time/money either. Slight extravagance, yes, but less silly than some other bike-related extravagances IMO.
I don’t know any super fast triathletes, but do have a pal who is a top notch Master’s cyclist and has been on the podium at Nats in his younger days. Let’s just say there was never a time I could even suck his wheel he is such a monster. I watched him ride a 52ish 40K before I moved to FL. He rides a 50-34 compact with an 11.
Yep - I just swap the big ring.
The bike shifts like crap on the stand with a 54-39, but with a little load on it, it works fine on the road if I shift careful. I wouldn’t
recommend it (the big tooth difference) for road racing where you’re shifts are important and unpredictable…but none of us will
be trying to respond to a Contador attack during a race.
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