livedarklions

Expensive Shot Emojis? K-Pop band name!

xroadcharlie

There are basically no hills here, Mostly paved overpasses, So my needs are limited as much by wind, which is probably average as hills,

On my typical 20 - 25 km casual ride I usually use only 5 of the 12 distinct, reasonably well spaced (<15% increase) gears obtained with the 3 x 7 speed drivetrain, from 49 gear inches (GI) against some wind to 78 GI, for riding speeds of between 15 kph @60 rpm cadence to 26 kph @70 rpm. That's a GI range of 160% of the 300% available. I seldom use the 89 GI high gear, And the only time I use the 30 GI cogs is climbing a short steep gravel trail near my home.

There's also an insanely low 21 GI option with the Shimano Megarange cassette that is handy for climbing that short steep gravel trail if I'm feeling lazy. But unfortunately nothing between it and 30 GI. I think I would really like something in the 25 - 26 GI range. Though it too would seldom get used.

Cougrrcj

I live along the southern shores of the glacially-scoured/scraped lower Great Lakes.. The only hills around here (within 25 miles) are river valleys, and even the Cuyahoga River (Cleveland) valley 25 miles south of Lake Erie is at most 200' deep. If I were to ride west from here, I could ride (and I actually have ridden) from here to Chicago - 350 miles - and not vary more than 200' in elevation. My work commute is 12.5 miles each way. The biggest 'hills' are highway and railroad overpasses, so maybe 30' of short hill-climb. So let's just say it is very flat here.

My bike gearing is - Fuji: 27x1-1/8 tires, 28/38/48 with a 13-21 six-speed freewheel. The Univega Viva Sport: 27x1-1/8 tires, 42/52 with 13-24 six-speed freewheel, and the Miyata: 700x25f/28r tires, 42/52 with a 13-21 six speed freewheel.

I generally ride in gearing that puts me somewhere between 75-85 Gear-Inches, with my normal cadence of ~90, that equates to a riding speed of right around 20-21mph. Of course the nine stop signs/stoplights tend to drop my average door-to-door speed down to around 17-18mph (42-44 minutes to ride the 12.5 miles) and that includes the slower speed for the last two miles as a 'cool-down'

BTW, this is coming from a 63+-year-old borderline 'Clyde' riding vintage steel bikes of somewhere between 24 and 30 pounds (depending on which bike I ride) as ridden including tool kit, spare tube, water bottle, pump, lights, etc.

freetors

Sounds like you'd have a good application for a single speed, especially if you're riding solo most of the time.

ofajen

We have flat, glaciated lands on the north edge of town, with modest hills in town and tumbling down about 200 feet to the river flood plain to the south and west. So some hills and some relatively flat terrain.

I won’t say it’s best, but for over a year now, both my bikes have been single speed. This summer I geared down just a tad, so the road bike is about 67 gear inches and the MTB is about 64. It’s been loads of fun and definitely provides a challenge!

Otto

mstateglfr 

Wheel diameter with specific tire size does play a factor in gear inches.
Sheldon disagrees with your arm length claim. Enter whatever arm length you want, the gear inches stay the same.
https://www.sheldonbrown.com/gear-calc.html

A longer arm does create more leverage, thats for sure true.

Jumpski

I live in Northern Thailand - 50/34 and 11-40 cassette.

Cougrrcj

Nope, ain't gonna happen... If SS is your thing, go for it by all means.
I use three gears as I accelerate up to speed. Trying to start out in a 85GI would put too much strain on the knees, and mine are shot. I'll also gear down a bit to climb those 'huge' overpasses for the same reason. I am a spinner, not a masher.. Besides, it is nice to have choices depending on wind strength/direction.

burnthesheep

Last night was repeats on our group hill loop. Gentle 2% grade up/back for a mile. The 56/42 combo was key to maximum smiles on the TT bike. So, 56/42 and 11-30 for the TT bike is 'just' right for me in this area. Plenty easy uphill and plenty fast down.

SpeedyBlueBiker

If I had to gear down to 34/40 I'd probably be on a hill that I shouldn't be on! 555
Having said that, I have climbed Doi Suthep on my LeMond triple, 52/42/30 with a 12-25 cassette.

CAT7RDR

I did a ramp that reached 24% on a 34x34. It was not fun, but those types of ramps do not come up often.

Frankly, it is the descents that concern me more at times.

Moisture

Leonard Zinn.

Moisture

Please do explain, if you do not mind.

I'm sure you and your physiotherapist are correct, im not questioning your observations or experience.

The Chemist

Here in the Yangtze River delta, it's pancake flat, with the only climbs of any note being inclines up on to bridges - these are neither particularly steep nor particularly long. I run a 1x9 setup with a 46t chainring and an 11-32 cassette, and it's more than enough gear range for my needs.

Branko D

He doesn't have proof that exactly 21% which he now advocates and sells, or 21.3%, is optimal, either. The few actual studies published on the topic which put trained cyclists on cranks of various lengths and found a small decrease in sustainable power only at extreme crank sizes. It's worth also keeping in mind that he sells people custom frames because extra long cranks on a mass produced frame which is designed for 170-175mm cranks reduce pedal clearance and change the handling.

The problem which is alluded to is, even if we agree taller cyclists would benefit from longer cranks in principle, the question is how do you get the ideal number. The numbers given by Zinn such as 21% and 21.3% suggest that I should be riding 175mm or 177.5mm cranks. 177.5mm? Yeah, no thanks!

​​​​Personally, when I was replacing a 175mm crankset with one with a power meter on one of my bikes, I went with 170mm cranks and the comfort is slightly better. I sometimes ride a bike attached to our turbo trainer with 172.5mm cranks and I can't say I produce any more or less power on it.

So, why not 20.4%? Or any other number in that range? Why not a range, say 20%-21%? Putting a precise number to it suggests that it's an exact science, and there is just nothing of the sort in it.

Anyway, on topic, within the confines of mass produced bikes and cranks (which, if you fall within 99% of the population height wise are appropriate for you), crank length doesn't have a meaningful impact on gearing selection.

Squeeze

My answer is under my screen name.

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burnthesheep

Lots of folks look at it only from scaling body dimensions and not consequences like hip angle.

Hip angle can affect power output.

Moisture

Branko D

From my own findings, which i have extensively detailed on this forum, something from 20.5% to 21.6%(max) seems to be a sweet spot, Its generally okay to go down a bit below 20.5%, but certainly not past 21.6%.

tomato coupe

Yes, you would certainly never want to go to 21.7%. That extra 0.1% would be almost 1 mm -- no way anyone could safely ride a bike like that !!!

PeteHski

My current road bike has a Shimano 50/34 compact crankset and 11-34 cassette. It's actually not a bad setup for my local roads, which have a lot of short but very steep climbs (20%+) and not much flat terrain. But I'm seriously thinking of moving to a 1x setup with something like a 40T chainring and 9-42T cassette (Campag Ekar).

My mountain bike has a 1x 30T chainring and 10-50 cassette. It's just about perfect for all-round trail use with super-steep climbs

Moisture

Try it yourself first, then come back 😑

livedarklions

Your own findings? Let me guess. N=1?

Moisture

And of course, you have nothing constructive to offer , right?

tomato coupe

No way. It's too risky.

1. Don't piss into the wind.
2. Don't cross the beams.
3. Don't exceed 21.6%.

livedarklions

I'll offer this--I suspect people vary enough in the proportions of their leg bones and hip bones that the idea that there's a universal ideal ratio seems pretty far-fetched.

I don't doubt that ratio works well for you, I just don't see how anyone could accept that as a generalizable finding.