Gearing - Do I need a compact

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rowdysluggins
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by rowdysluggins

I tried a compact and didn't like it. Maybe I just didn't use it enough to get used to it, but it didn't seem to shift as well, and the front shift required too many rear shifts to compensate. When I built my R1, a little over a year ago, I decided to try the newly available DA 9000 52x36 up front (kind of a compromise between compact and regular). I initially combined it with a 11x25 in the rear (I used a 12x25 on my 10sp setup), and I really liked the wider range of gearing. It gave me a higher high (52-11 vs 53-12) and a lower low (36-25 vs 39-25), and seemed to shift much better than my experience with the compact. I'm a decent climber, and I regularly do climbs that sustain over 10%. I practice a lot of out-of-the-saddle climbing, and always pull it out of my bag of tricks when the going gets rough, or my quads need a break from sitting. Just recently I decided to try an 11x28 (so it skips the 16). I've ridden it a couple of times, including one of my regular mountain routes, and although I only used the 36-28 a few short stretches, it was nice to be able to sit and spin for a change, when I would have otherwise had to stand. I didn't miss the 16 on the varied terrain I was on. It might be a different story on a flat ride where I really wanted to sustain a perfect RPM. I ended up setting a PR on the 6 mile climb.

NiFTY
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by NiFTY

I would say it depends on your climbing style. I also climb a lot and run a standard, I am 72kg. Until recently I rode 25 as my biggest sprocket. I now have a 28 on one of my two bikes as a bailout gear for steep stuff (ie 15% grade)

Looking at a few of my climbs I did a 7km 5% climb in the 23 and 25, averaging a cadence of 85 @ 333W
5.7k @ 5% in the 23 and 25 at 89 @ 339W
A 4.6k climb at 8% in the 25 and 28 predominately at average cadence of 81 at 335W

I used to really grind (before i had my powermeter when i was stronger), my PB on the local hill 2.2k at 9%, was set on 39x21 slipping occasionally into the 23. I don't have a power/cadence for this as it was pre-stages. But probably a cadence of 75 dipping to 70. My closest recent effort (17 seconds slower on a 7:33 climb) was 397W at 85, in the 23 and 25.

In terms of compacts and endurance I everested a 7km 6% climb (short ramps to 12%) (22.5 reps) on a 39x28. 320K, 8.9 vertical k's. Compacts are not necessary but that said i have entertained the idea of a 52/36 for the sustained steep stuff (ie >5K at 13% or steeper) and think it would increase climbing speed on those gradients.
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HillRPete
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by HillRPete

OP: the cost pov is a strong one. For like half a year just get a cheap cassette by all means.

Generally I'm amused that so many cyclists are still trying to get away with the hardest bottom gear, the narrowest tyres and the highest pressure that works for them, in this day and age. Tradition is strong. But when you're not cruising close to 40kph most of the time, a compact will give you a better chainline and save front shifts.

Finally on the argument of cadence -- aerobic vs muscular strength -- isn' that just old lore? Where does the muscular strength for a climb of any significant length come from? From the aerobic metabolism, clearly. There is no other way. Masher vs twiddler it's a personal preference.

NiFTY
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by NiFTY

Pete, low and high cadence obviously both utilise aerobic metabolism. But the amount of mechanical "work" done to generate the same watts at a high or low cadence is the same. So it comes down to how one prefers to generate that work. Some people swear by high cadence, BUT as the elevation in respiration is not generated by elevated blood CO2, decreased blood O2, but in fact by muscle stretch receptor activation/joint movement feeding into the brainstem it depends on peoples reactivity to such stimuli as to how they will react to low cadence high load, or high cadence low load. We all know that a higher cadence tends to lead to a higher heart rate and presumably helps clear lactate, BUT a higher heart rate does not necessarily increase oxygen delivery to tissues. This is why rapid heart rates such as in SVT or AF with rapid ventricular response make people blackout.

Finally one only needs to look at two 2 pro-cyclists that have vastly different approaches - contador and froome for instance, with similar outputs and results. Froome rarely out of saddle and higher cadence, contador pushing a bigger gear at a lower cadence (tends to run a large cassette to stay in the big ring longer), out of the saddle more often
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fromtrektocolnago
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by fromtrektocolnago

eric wrote:I do a lot of climing and climbing races. Cadence is a personal preference. Some people do best at higher cadendces, others can handle lower cadences. Low cadence tends to tire the muscles faster. But some of the faster climbers I know use relatively high gears and low cadence.

Generally heavier riders seem to prefer higher cadences and lighter ones can get away with lower cadence but that's a gross generalization.

Also realize that doing a single climb when you're fresh is different from doing the same climb after 4000 meters of climbing that day and 4500 the day before.
And getting up the climb is different from racing it like the (race leading) pros do in a mountain stage of the tour.

You have a lot of room for lower gearing with your current chainrings. Unless you're planning on doing some big climbing rides or steeper climbs or some other large increase in your climbing you can get by with a larger cassette. If you find that's not low enough then get the compact.


I do a fair amount of climbing, on a 53-39 and 11-28 set-up. It's served me fairly well, and the non-compact set-up has never really prevented me from going up any hill. I've even gone up hills such as Devil's Kitchen in the Catskills which is Cat 2 with peak grades in the low 20's. That said my cadence is definitely slower as a result of the gear selection, which suits my riding style(spinning for long periods tires me out more than grinding). I do think that in attacking something like Devil's Kitchen a compact would have been an interesting tool for the task as my cadence in that segment was low for me, even by my standards. I don't view a non-compact set-up as tiring me out over a hilly day, as I'll combine this type of training with centuries.

For comparison however my friend did the same Devil's Kitchen segment in compact and he struggled with it. Gearing can optimize a ride, but its no substitute for training
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Nefarious86
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by Nefarious86

jpanspac wrote:Another factor is how fast you want to go down the hill. You'd spin out a lot sooner with a compact crank. If you're content to coast down it doesn't matter so much.


50x11 is actually taller than the 53x12 a lot of people run, factor in that I can spin to 140rpm if need be and I've never run out of gears before I tuck the top tube.

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bigfatty
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by bigfatty

"Gearing can optimize a ride, but its no substitute for training"
I agree, I will work away at my 39, I am just starting club rides so I have room for improvement. I could lose at least a kilo of my bike and at least 3 or 4 of the bones. this will help me spin up to 80 in the same gear.
regrads 20 degrees and more, this is really not my style, road bike for me is long climbs up to 10% average. any ramps i just will grind through but I think with a 27t I could still keep it in the 60rpm range. I have a mountainbike for steep offroad stuff.

What I am really interested in is the cadence people are spinning on long steady climbs. I feel anybody does not spin much more than 90. Even looking at Froome he seems to ride about 90 when he is not going "all exterestial" on his attacks. This is about 10rpm higher than the average peleton climber, so really not that much in it, not a super high cadence.

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bigfatty
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by bigfatty

From Team Sky camp saying Lower Cadence translates into more power for Wiggins:

http://www.telegraph.co.uk/sport/olympi ... trial.html

Kerrison booted up his computer, did the maths and concluded that Wiggins’s cadence, sometimes in excess of 105rpm, was too high and not all of that power from one of the biggest engines in cycling was getting transmitted through to the bike.

This year Wiggins has dropped the cadence slightly and rides in a higher gear.

“Without boring you too much with the technicalities I averaged 456 watts for 55 minutes at the Worlds last year against Tony and still finished 1min 20sec behind.

"He was fantastic that day but it seemed like I should have been getting more return for my effort,” said Wiggins.

“We’ve dropped the cadence and I am trying to power my way along a bit more, get more distance per pedal stroke. It’s been working well this year and it has helped my strength generally.

"It’s going to be tough but I have a very realistic chance. I’m going for gold.”

NiFTY
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by NiFTY

So bigfatty i would say for 5-7% climb i would be 85-95 cadence. Averaging 90. For a 9-10% i would sit 75-85. Over 10% - whatever i can turn out. I sit 95-100 on the flat. I have never ridden compacts, I am an obligate in the saddle climber unless it is very steep.
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rowdysluggins
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Location: Taylosville, Utah

by rowdysluggins

Nefarious86 wrote:50x11 is actually taller than the 53x12 a lot of people run, factor in that I can spin to 140rpm if need be and I've never run out of gears before I tuck the top tube.


It's still not as tall as a 52x11 or 53x11, (and believe it or not, I use my 52x11 quite a bit, and enjoy having it).

airwise
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by airwise

When compacts arrived on the scene, the largest sprocket on a cassette was typically 23/25 tooth and we were using 9 speed drivetrains.

Now we have eleven speeds and cassettes up to 29/32 teeth bottom gears.

So in reality, it's perfectly possible to replicate the gearing of the original FSA compacts with a modern day standard crankset without inefficient spacing.

Having said that, there's a small weight benefit from running a compact chainset with a close ratio block and I personally prefer that. The times I might lose out not having a 53/11 are so few it's not worth my worrying about. I find myself pushing bigger gears now though. Cadence is only part of the equation - efficiency of the pedal stroke is equally important and if that suffers because you are wobbling around spinning like a top then lowering your cadence will often result in more power being delivered where it matters.

dunbar42
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by dunbar42

rowdysluggins wrote:I didn't miss the 16 on the varied terrain I was on. It might be a different story on a flat ride where I really wanted to sustain a perfect RPM.


FYI, with the SRAM 11 speed 11-28 cassettes you don't lose the 16T cog. I run a Force 22 11-28 cassette on my Shimano 5800 setup. Works fine.

ricey155
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by ricey155

Never had any option always ran compact, I've toyed with going 53/39 but never bothered learned a lesson this week on the burway no39 UK climbs - just make sure you have 1 extra to fall back on

I didn't 36 - 28 but the 28 decided to click the wheel so 36-26 needed to bloody stop which is a killer [THUMBS DOWN SIGN] so 34 is going on for next visit (and no carbon aero wheels this time)

Learn the hard way by trial and error

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rowdysluggins
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by rowdysluggins

dunbar42 wrote:
rowdysluggins wrote:I didn't miss the 16 on the varied terrain I was on. It might be a different story on a flat ride where I really wanted to sustain a perfect RPM.


FYI, with the SRAM 11 speed 11-28 cassettes you don't lose the 16T cog. I run a Force 22 11-28 cassette on my Shimano 5800 setup. Works fine.

On DA you loose the 16 going from 11x25 to 11x28, on SRAM you loose something, I guess you don't know what?

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istigatrice
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by istigatrice

rowdysluggins wrote:on SRAM you loose something, I guess you don't know what?

You lose a bit of dignity running SRAM :lol: [/humour] :wink:

On a more serious note, the SRAM cassette ratio is: 11,12,13,14,15,16,17,19,22,25,28

Compared to the Shimano the back end is quite different: 11-12-13-14-15-17-19-21-23-25-28

The 19 goes straight to a 22, so there's no 21 or 23.

Compact gearing? I'm quite happy with my 53/39 paired with an 11-28, but then again, the hills in Adelaide are more like rollers compared to actual mountains. A few of my friends who've been to France/Italy would recommend a 50/34 for climbs over there, but they run a 53/39 back home. I guess it really depends on terrain.
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