I’m thinking about upgrading to a crankset with a 54T big ring, but is that a good size for a triathlon? I know people use them for TT, but wouldn’t a 54T make you more tired in a tri?
Pros:
Cons:
THANKS!
How would your chain ring make you more tired?
Bigger chainring would cause you to apply more force to more it, would it not?
This is why I’m asking for the pro’s and con’s.
Right now I’m deciding between a normal 53T SRAM Red Crankset or a 54T TT SRAM Red Crankset.
Are you regularly “spinning-out” your 53x11?
I run a 50/34 Crank right now.
I don’t spin it out unless i’m going down hill, which there are a lot of seeing out I live in Virginia (not the flat part either!).
I have a 54 tooth “Q Ring”. I could probably get by with a 53 but when I’m riding with a 25 mph tailwind in a local TT even that’s not enough.
So you are thinking of switching from compact crank to a more “standard” configuration? What gears are you or do you plan on running in the back?
If you are frequently riding in the 26-30 mph range and like to ride lower rpm’s, maybe a larger ring would help you get a straighter chainline, is this what you are looking for? Simply changing the gearing won’t change your speed, you could have a 90 tooth chainring and would just need to be in a larger cog in the back to maintain your race day speed and rpm’s.
It’s just a matter of what rpm’s you need to ride to make most power, what speed you ride and what gives you a good chainline, nothing more than that.
Go here and look at the gear calculator. You can play with different gearing combinations and see what speed you will travel at any given RPM.
http://www.sheldonbrown.com/gears/
for example with 175mm cranks, 90RPM in an 53x11 = 33.9 mph. switch to a 54x11, you are at 34.5mph. Not a huge difference.
11-23 - 9 Speed Dura-Ace Shimano Cassette
.
I run a 50/34 Crank right now.
I don’t spin it out unless i’m going down hill, which there are a lot of seeing out I live in Virginia (not the flat part either!).
What is your typical cadence? What gear combination would you say you ride in “most of the time”? I truly love the range I get with the 50. It suits my power range better than a larger ring, meaning I can use a wider selection of the cassette than with a 53 or larger.
Lets say you are typically in a “50/18”. With a 53, you’d be higher in the rear to achieve the same gear ratio, maybe the 21. You’d have a decreased selection of gears available to you in your power range than you do with the 50. Just slapping on a bigger ring really means nothing as you’ll just seek a corresponding gear ratio to what you’re comfy with in your 50.
If the goal is to spin a constant RPM of about 90 or so, bigger front chainrings would be sort of limiting in that respect - you’d have to go to the small ring more often. The way I’m set up I can stay in my big ring and spin fast on everything other than truly steep climbs.
Like others said, unless you are spinning out your 53-11 or rather your 50-11, than a 54 ring isn’t for anything more than show and bragging rights .
Since you are on a compact crank right now, you would need an entire new crankset if you want a 53 or 54 tooth big ring. keep that in mind.
Just don’t let Dev Paul see this…I think he rides a 48t big ring and i think he’s in the 2:10-2:20 HIM bike range…suffice to say, a 53-54t ring is probably not what’s holding you back.
I have a 57. I would ride the exact same way if I had a 54 or a 50 as I would simply be choosing a different cog in back to account for the terrain. The only difference is I don’t spin out as quickly on the steep downhills.
Chainring size? It depends. All have 11-23 cassettes.
Daily driver and climbing bikes have compact cranks. 36x50 except on hill climb day. Then I add the 34.
Crit bike - 39x53. TT - 44x54. No hills on the TT and I have a little more umph on race day.
Do I use the 11s? Rarely and never on the TT, but I. But I’m more comfortable with a 54x15 than a 53x14.
Based off the number of people I pass in races with my 50x14 high-end, I would say that 99 percent of all triathletes are overgeared. With a run at the end, once you pass about 25 mph there is no sense to even pedal with any effort. I’ve used a 48 often enough for duathlons where I’ve averaged 24 mph. Pro cyclists need a 54, maybe some really good time trialists who don’t run afterwards; nobody else does.
Chad
when yer kid asks you “WHEN AM I GOING TO USE MATH/PHYSICS IN THE REAL WORLD”
you can tell him, if you ever become a cyclist or automotive enthusiast, learning this will allow you to be one of the few people that understand gearing. allow you to crush dreams and make fun of ignorance on the interwebs.
using a bigger chainring won’t make you more tired. it simply affords you a higher top speed for a given cadence, and rear casette, and also a higher ‘minimum’ speed.
There is no chainring that is “Good for triathlon”. The ideal chainring depends on your minimum and maximum speeds in a given event, and your rear casette.
you gotta do the math
in general, you don’t need a 54 if you are using 700c wheels, even if you are fabian cancellara. exceptions: you prefer a very low cadence, or are doing a course with extended downhill sections.
dude, in the events coming up i plan to be past 25mph the whole time!
still wont need a 54 though
Based off the number of people I pass in races with my 50x14 high-end, I would say that 99 percent of all triathletes are overgeared. With a run at the end, once you pass about 25 mph
Chad
in general, you don’t need a 54 if you are using 700c wheels, even if you are fabian cancellara. exceptions: you prefer a very low cadence, or are doing a course with extended downhill sections.
For the ToC this year, Cancellara did use a 54/44 for the prologue TT 
But it was a flat 4km course with 90 or 180 degree corners.
Anyway, for my legs, I don’t need more than a 50x11 unless I’m hitting mid 30mph for extended periods of time (5 min +)
I use a 55/42 with a SRAM Red 11/26…it is fine for everything except 15% grade or higher.
“dude, in the events coming up i plan to be past 25mph the whole time!”
I know I’m not telling you anything you don’t already know but last year at the Austin Triathlon there were only about 4 guys that averaged better than 25 mph. If this is one of the events on your schedule good luck and I’ll really be impressed if you actually do that.
I haven’t looked at the results from last year but I’m sure averaging 25 mph at the Longhorn 70.3 will be no walk in the park either.