Why the move to compact cranks?
 

This may not belong in this forum, but we often discuss upgrading our C&V bikes with modern components. I currently ride a 1x6 with Campagnolo Nuovo Record cranks, a single 52t outer ring, and a 13-24 freewheel. I live on a flat island and only use the 2-3 smallest cogs on the freewheel. It's so flat here that I used to exclusively ride fixed gear, but I wanted those extra gears for when I am riding into the wind.

Modern bikes seem to be moving toward compact cranksets with smaller chain rings and larger cassettes. Why is this? I was told it had something to do with pedaling efficiency and maintaining a steady cadence.

I am toying with Rivendell's Sugino XD2 compact crank which is 40t x 26t with a chain guard on the outer ring (https://www.rivbike.com/products/sug...rank-40t-x-26t. I'm not sure if I can get a larger freewheel for my Shimano 105 rear hub. I'm not even sure why I want to do it except I am intrigued... and I like the idea of pedals that taper out.

So what is the argument for smaller chain rings and larger freewheels/cassettes?

You can get a wide gear range without a triple.

This is a good piece on the topic, http://www.bikehugger.com/posts/the-...compact-crank/

Hills? Being a flat-lander myself I found out the hard way, when I took my touring bike with a 47 x 22 lowest gear for a ride in the Ardennes a few years ago. Walked most of the day.

My latest build sports this combo. 49/28 and 14-32:

https://myalbum.com/photo/5tyJRtVyX3IX/1k0.jpg

People are weak.The day that I will use anyting smaller than 38(130bcd) x28 is the day I die.And yes I do mountains( cat. 2 max here)

A lot of rock and roll musicians had the same attitude. Some of them got old, and are still enjoying life.

39 x 26 was my cutoff, and I did the Markleeville Death ride in my late 20's with that.

35 lbs later and, er, a few decades later, I still enjoy riding. A 25 gear inch low end keeps me going up the same hills, just slower.

Hopefully you'll get there someday.

#1) Mountain bikes and the low gears allowed a lot of folks to climb hills comfortably if slowly.
#2) Higher cadence is recommended by some cycling efficiency theorists.
#3)A 110 bolt circle provides a lot of chainring options.

I got one for my CX bike but I doubt it made me faster and I have one now on my utility bike that pulls a trailer with 60 to 80 pounds of groceries up a short hill to the house.

Ride what you want to ride. There is no right or wrong. If someone is riding hills with a 39/24 and they are happy, they are fine. Don't take someone else's gear decision personally or to mean that your decision and thought process is somehow flawed. It's like asking what is your favorite color and arguing about it.

love to see you pull my trailer loaded with two bikes up main street hill in peoria il. with 38-24. if you can do it you are the man or woman!

Sounds like you already have a great setup for flatland riding. (Knock the chainring down to a 48T and I could be very happy with it around here.) Not sure if you'd ever find much use for the super-low gears you'd get with that Riv crank.

This view is heartily endorsed by my right knee :P

I suppose it's OK to talk tough while ya gots the stuff, but man, most of us get old before we die, and most of us still want to keep riding.

Compact cranks are just another choice, lots of people like them, choice is good. That's why they make chocolate and vanilla.

My regular ride. My middle gears get hardly any use.

https://lh3.googleusercontent.com/wz...-=w574-h951-no

I (finally) moved away from big 52 and 53 rings a few years ago and am quite happy with the compact set ups I have on many of my bikes. Yeah, I still have big rings on my Paramount and Freschi, but those bikes would be weird with little chainrings. My ability to spin now outweighs my (passing) ability to mash. I think there's likely a similar train of thinking with the growing popularity of compacts...that granny sure is fine when you want to keep spinning smoothly!

Maybe related, maybe not - but I was on a group ride this weekend and noticed a HUGE number of riders with REALLY tiny chainrings. Maybe I've had my head in the sand, but I was only just at this moment paying attention to how many were riding singles up front with - oh, I dunno - maybe a thirty tooth or smaller chainring? I mean, just nutty small stuff.

http://www.reactiongifs.com/r/lucille-portable.gif

Wasn't that the theory behind "micro drive" around 1990 or so?

Ranger Station?

Compact cranks aren't new for bikes set up for touring. I've seen literature from the 70s describing TA pro-vis-5 cranksets configured with 45/28t rings and a 5-speed block.

A couple of months ago I bought a '16 Specialized Diverge. I immediately replaced the compact crank, which I despise, with a 52/39. One member, a youn 'un I'm sure, replied with a smart ass comment saying I should ride in the Tour de France or something like that. The new generation actually believes a 39T is too big. They wouldn't have made it when most road bikes came with a 42. Some groups didn't even have an option for smaller than a 42 (Campy, Biopace, ect).

On one of my Univega's I bought a new Sunrace freewheel. They only come in a 14-28, which is mountain gearing IMO. I swapped out the 39 for a 42 because it just works with it better. And I'm about to turn 50.

And don't forget the sales benefits of the "latest and greatest"!

My wife thoroughly enjoys her compact Ultegra setup (11-40 11-spd cassette, 34-46 rings), and although a frequent and strong rider, especially for someone in her 6th decade after two bouts of breast cancer, rarely uses the big ring, which is a strong tailwind/pedal downhill (rarely) set of gears for her. I think she appreciates the simplicity of just shifting the rear. The 11-spd setup became a requirement in order to get the hydraulic discs that she needs with arthritic hands in a hilly environment. Her gearing range is intentionally the same as her previous bike (12-30 8-spd, 24-38-48 rings).

For me, I enjoy the thinking (and doing) process of shifting my triple (12-30 8-spd, 24-36-46 rings), and the small steps between my flat road gears on the custom cassettes I assemble. And I'm pretty heavily invested in my 8-spd Sachs brifters!

It bugs me when I see comments about "the weight penalty of a triple". The only extra weight is the granny ring and it's bolts! I wouldn't be surprised if the weight of those larger cassette cogs and the longer chain to accommodate them on a compact double is greater.

My other personal beef with compacts is that my typical cadence and desired speeds would have me cross-chaining extensively and making lots of front shifts with corresponding multiple cogs in back. But I'm old.

Anyone using a derailleur is weak.

And I don't do mountains. That's disgusting.

Aye, to be 50 again!

And here's a 40/24 from 1947, if I'm right in counting the teeth. :)

https://janheine.files.wordpress.com...sech1147_0.jpg

P.S. Come to think of it, Campagnolo hadn't even started making cranks yet. ;)

It's good to be ahead of my time...:D

Back in the '70's I ran this on my Bottecchia. Looks like a 52-32? I had a somewhat wide 5 speed freewheel too, looks like about a 30 on there. Lots of mountain riding in those days. That was really the point of a wide range double, a gear for pretty much anything. The gaps could be a bit big but that bike could do whatever I wanted to do. I think now, with all the gears available the smaller chainwheels work. You can put more in the back, and run a 12-whatever, which when paired to the front still gives you speed gears and the ability to climb.

I'd sure like to have this crankset now, and the rest of the drive train for that matter!

https://farm6.staticflickr.com/5475/...1dd635fe_b.jpg1979 Bottecchia 004 by Ed Lutz, on Flickr

https://farm6.staticflickr.com/5626/...38527846_b.jpg1979 Bottecchia 002 by Ed Lutz, on Flickr

This may be close to the truth: Cyclists used to handle 42/23-4 all the time. I'll admit that I am tired on the last hills of a 60-mile ride on my standard 39/28 setup, but it is not the bike's fault that I am too lazy to do my pre and post ride stretches and isometrics.

Also, the reason compact cranks came out was the same reason disc brakes, integrated brake-shifters, sloping top tubes and carbon frames appeared: Because bike designers needed to come up with something that would compel and convince riders that their bikes were obsolete and that they needed new ones. As they say, "The truck backed up.., and everybody got in."

With the help of Frank Berto, I put together this compact system, for loaded touring (early '80s). Rear block is 13-15-17-20-28-34, chainring is 46/32T. Gives me a low 25 GI. This year (I'm 70 now), I put the smallest inner chainring allowed (80 BCD) a 28T, giving me a 22GI. This will keep me going for a few more years, I hope.

With the exception of Campy Athena crank, I have a 34T inner chainring on all my bikes.

This is the original setup. Now I have a 28T inner chainring.
Attachment 580297

Attachment 580298

Last time I did that ride I only used my middle gear. 42 x 17. (Fixed.) I did walk the final steep bit. Coming down caused more pain than going up. But seriously, that is one place triples shine, especially if you are starting out in Alameda (island).

Ben