lupo68288

My FTP is at 211

hubcyclist

you dont need a 52-36 to race with your power. my ftp is 305 and I ride a compact and rarely am ever at the highest gear, and even when I am I'm not spinning out. and this applies to both racing and non-racing riding I do

Maelochs

This could be the most favorable information in the thread---essentially, OP, just buy your bike and ride it a lot and everything will be fine.

wheelreason

We are missing the point somewhat. It's not all about having bigger gears, it's where the gears lie in your power band. In a straight block, or single tooth changes as found near the chain stay. As you move to smaller cogs, the difference between each shift will be greater. so if you are in a 53/15 (my al time favorite gear) a shift to the left or right will give you a smaller change than if you were on a similar gear with a 50 ring and the corresponding adjacent cogs. This negates or reduces that too big/too small feel when you shift, specially if you are at or near upper effort limit...

tomato coupe

True in principle, but the differences are pretty insignificant. For instance, shifting down one gear from the 53/15 causes a 6.7% gear drop, whereas shifting down one gear from the (nearly) equivalent 50/14 causes a 7.1% gear drop.

chaadster

Yes, you are right, and part of the explanation is to do with torque at the pedals.

Torque is the force we apply at the pedals, and is the best measure of what we feel, our perceived pedaling effort. Assuming the same rear cog and same crank arm length, a drivetrain with a lower tooth count (i.e. smaller) front chainring will require less torque to pedal through a rotation. Depending on the particular make-up of any given rider— like ratio of fast twitch muscle fibers to slow twitch, their body mass, pain tolerance, aerobic and anaerobic capacities, etc.— the range and amount of torque they like to work with will be variable.

We can move around the gear range in the cassette to get equivalent or similar ratios with different chainring sizes, but how they feel at the pedal is largely a function of the leverage created by the crankarm length acting on the diameter of the chainring. It’s calculable, measurable, and tangible.

As somewhat of an aside, I used to be more familar with torque values because the old Powertap analysis software, PowerAgent, used to display torque, but since that went away— well, it’s no longer supported/updated— I haven’t looked at it at all, but I know Golden Cheetah will display it, so that’s a good resource for cyclists who are interested in understanding that aspect of their performance and gaining insight into optimal gearing choices.

tFUnK

I ride 50/34 and don't ride fast anymore but if I were racing or interested in speed I'd definitely go with 52/36 or the 53/39. The differences may be small but they're there. The 52 or 53 just feel better if wanting to go fast on the flats or the descents. It could be due to the slightly smaller jumps when shifting up and down the cassette, or it could be that marginal drivetrain efficiency improvement when pushing 53/12 vs 50/11, or which cog positions the chain spends the most time in while in the pack. Incidentally, I also feel I was able to pedal smoother on a 53t vs. a 50t. On paper I wouldn't have thought there would be such an appreciable difference but the legs and the Strava do not lie.

If crit racing is the game then I would go with a 1x setup.

And nowadays with 11 or 12 speed and 32t+ cassettes, you can still maintain those close gaps in the taller gears. I'm still riding 10 speed and hate having to choose between keeping my 16t or having a lower climbing gear.

genejockey 

One thing I keep reading on threads about gearing is that you won't spin out a 50x11, or you'll never use a 52 or 53 x 11, because nobody who doesn't race professionally could push that gear on the flat, etc. But, you know, sometimes you want to go fast without your legs whirling like an eggbeater. I'm not really a huge fan of spinning at 120 rpm, though I can do it if I need to.

For example, there's a half-mile, straight, 3.5% descent on my Sunday ride, where I can generally get up to about 35-38 mph with a little effort. (Then the momentum carries me part way up the next rise, which is more like 6%). I end up in my highest gear at a low cadence, gently adding force to the acceleration of gravity, precisely because I can turn the pedals over slowly. It's after an almost mirror image climb, which I tend to push hard on because of the descent waiting at the top.

Anyway, "spinout" speed is only one factor.

jonathanf2

The nice thing if going 1x, is that you can really fine tune your cogs as well especially on an 11-12 speed cassette and/or even adjust chain line with spacers or an offset aero chainring to create an optimal sweet spot. If I was building an exclusive flat course race bike, I would keep it very minimalist.

Broctoon

I don't know about torque at the crank and how hard a rider has to push on the pedals as a function of chainring size alone. To me, a given gear ratio (in gear inches or whatever units you prefer) is the important thing. I think you're trying to say that some riders can better achieve a given level of power at higher cadence and low torque, vs. other riders who produce the same power at low cadence and high torque. This is true. Claiming there's a difference between two sets of gears, different sizes but with the same overall ratio? I'm not buying it. Some components of the bike might notice a difference. The drivetrain's efficiency will be a little less or little more--hardly enough for any rider to notice. To the legs, 75 gear inches is 75 gear inches (with a given wheel size and crank arm length).

Broctoon

That's exactly what I have on my road bike currently. I had a 52/36 for about three years, but now 53/39, because of reasons that belong in another thread.

I am not very strong. And yes, I go up some fairly steep climbs sometimes. I mostly ride just for fun and fitness, but I enter the occasional race, various formats. You really can't go wrong with that cassette range and either a road standard or mid-compact crank.

chaadster

You misunderstood, as I explicitly said I was assuming same cog, same crank arm length, but different chainring tooth count, so that cannot be the same gear inches.

PeteHski

Like @Broctoon said, it doesn't matter how you achieve an overall gear ratio. Obviously a larger chainring makes all the gears on the cassette taller. In this case there is so much overlap between a 52/36 and 50/34 that it only makes a difference for the lowest and highest gears. If there are steep climbs involved I would prefer the 50/34, otherwise I wouldn't care either way.

chaadster

Again, I was explicitly stated the terms were about different gear ratios, which is exactly what one gets if they change only chainrings. I was directly addressing TiHabanero ’s observation that bigger and smaller chainrings do, in fact, feel different because of how leverage affects torque application. Simple physics, I think, and not at all mysterious, just oft overlooked. But, we can introduce changes to crankarm length to the discussion if you guys want to talk about gear inches and feel…

Eric F 

Of course it requires less torque to pedal through the rotation. It's a smaller gear.

Trakhak

A highly successful track and road sprinter I knew decades ago once told me that he was delighted when the other guys started switching to 53-tooth big rings for road and crit races. "I've used a 50-tooth ring for years," he said. "This'll just make it that much easier for me to get the jump on them at the end of the race."

chaadster

To people like us, sure, but this discussion is proof it ain’t so for everyone:
Anyway, to restate the context again, I was addressing the comment about being aware, but unable to explain fully, why rings feel differently to the legs.

Eric F 

I would bet it worked for him because it fit his style - high rpm and (probably) an explosive late jump. I could never complete with those guys if I waited to play their game. For me, a fast leadout, and crushing a 53x11 while everyone else was still waiting to jump was much more successful. Being the first one to go made everyone else have to react and play the game my way, where I was using my best weapon. Once I figured that formula out, wins started coming. My way worked for me, with the way my muscles are most effective, and the way I trained my strengths. For others, a smaller gear may be a better choice.

tomato coupe

My comment preceded anything you wrote, so the context of your statements has no bearing on mine.

chaadster

Correct, I used your comment in regard to a different point. I can see the way I wrote the post made that unclear. Sorry.

Maelochs

Just leaving this here for when everyone else is finally tired over picking nits and such ......

Of course, the same was in Post #3 and mentioned elsewhere in the thread .... but we aren't here to spread knowledge or share wisdom ... it's the internet, dang it, and if it ain't porn it's an argument!

Of course this might all be some sort of abstruse porn and I am simply not refined enough to be excited by it ....

Broctoon

Sorry. I missed that part. And yeah, obviously there’s a different feel when your gear ratio changes because of a change in chain ring size.

This is the part that made me scratch my head:

”We can move around the gear range in the cassette to get equivalent or similar ratios with different chainring sizes, but how they feel at the pedal is largely a function of the leverage created by the crankarm length acting on the diameter of the chainring. It’s calculable, measurable, and tangible.”

Um, no. It’s not a function of the chainring diameter. It’s a function of the ratio of chainring teeth to cog teeth. Any explanation more complicated than that is a waste of words.

chaadster

Well, it’s a matter of simple physics, that’s all there is to that. Look it up; leverage is really a very basic concept.. I mean, you could go and spin the crankset of your bike with your finger both in the spider as close to the spindle as you can get, and then again out at the end of the crankarm; you should easily be able to feel the difference in force required to turn it at each location. It’s the same thing that happens at the pedals, just that the forces are larger, acting over a force range (i.e. torque) of something like 10nm to 190nm.

The ratio of chainring teet to cog teeth does not at all describe the amount of force required to turn the geartrain.

tomato coupe

Yep. Chain ring size doesn't change the torque at the pedals if the gear ratio is the same, as long as the crank arms are the same length. (Assuming everything else remains the same, of course.)

SpeedyBlueBiker

52/34 would be a very wide range of gearing. Would a 11-34 cassette work with this kind of set up?
As to the OP's original question, I think 52/36 would be better for racing.