42x18
#1
Senior Member
Thread Starter
Join Date: Mar 2021
Posts: 1,995
Mentioned: 24 Post(s)
Tagged: 0 Thread(s)
Quoted: 2700 Post(s)
Liked 486 Times
in
351 Posts
42x18
Hey guys, I recently got a single speed and its gear ratio is crazy low at 42x18. This seems lower than most riders, the fixie kids would laugh at me. My first thought was to up the ratio, but im having to spin super fast in order to keep up on the group ride and I wonder if this is good training, I kind of think it is. Does anyone else run a low ratio like this for training purposes? they say spin to win...
#2
Full Member
Depends on your goal. I ride a 42x16, but that is a touring rig in mountainous/hilly terrain with full load. For mountain bike riding I use a 32x16.
If trying to keep up on a group ride, what gear-inch do you spend most of your time then get a single speed around that and see how you do!
Good luck!
If trying to keep up on a group ride, what gear-inch do you spend most of your time then get a single speed around that and see how you do!
Good luck!
#3
Senior Member
Join Date: Jul 2002
Location: Sacramento, California, USA
Posts: 40,865
Bikes: Specialized Tarmac, Canyon Exceed, Specialized Transition, Ellsworth Roots, Ridley Excalibur
Mentioned: 68 Post(s)
Tagged: 0 Thread(s)
Quoted: 2952 Post(s)
Liked 3,106 Times
in
1,417 Posts
I tend to mash, so I intentionally keep my ratio low on my SS/FG bikes to force myself to spin. It's easier on the knees in town and it's good to get comfortable at a higher cadence out on the road. Typically, I'll do 42x16 for the road FG. My SSCX is at 41x18, which really makes me spin on flat tarmac, but it's as high as I can go on dirt and grass.
#4
Cheerfully low end
Join Date: Jun 2020
Posts: 1,978
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 646 Post(s)
Liked 1,044 Times
in
667 Posts
Hey guys, I recently got a single speed and its gear ratio is crazy low at 42x18. This seems lower than most riders, the fixie kids would laugh at me. My first thought was to up the ratio, but im having to spin super fast in order to keep up on the group ride and I wonder if this is good training, I kind of think it is. Does anyone else run a low ratio like this for training purposes? they say spin to win...
Turns out that the internal power requirement is independent of the external power delivered to the pedals but strongly dependent (as we would expect) on pedal RPM. This makes sense because it’s just the work we have to do to move the mass of legs, feet, pedals and cranks around as we pedal.
So, we spend more W/kg spinning our legs fast than we do spinning them slow. For example, at 110 RPM, the internal work runs about 1 W/kg, which is already significant and it is a sharply increasing function at this point. By comparison it will only be about 0.1 W/kg at 50 rpm.
So, in addition to protecting knees from greater forces and strain, you will also work your body somewhat harder at a higher cadence (for the same actual speed on the bike).
Otto
Likes For ofajen:
#6
Cheerfully low end
Join Date: Jun 2020
Posts: 1,978
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 646 Post(s)
Liked 1,044 Times
in
667 Posts
I recently changed my Schwinn road bike from 42/16 (70.9 gear inches) to 40/16 (67.5 gear inches) and I think if anything I’m riding faster and stronger overall at the lower gear.
I made this change to help reduce long term strain on my knees, but it seems to also be just as effective. Also, our trails are a lot rougher after massive flood damage and repairs, so average speeds tend to be down a bit and there is a benefit to slightly lower gears in negotiating those routes.
Thinking about also changing the RockHopper from 42/16 (68.3 gear inches) to 42/17 (64.2 gear inches) and see how that goes.
Otto
I made this change to help reduce long term strain on my knees, but it seems to also be just as effective. Also, our trails are a lot rougher after massive flood damage and repairs, so average speeds tend to be down a bit and there is a benefit to slightly lower gears in negotiating those routes.
Thinking about also changing the RockHopper from 42/16 (68.3 gear inches) to 42/17 (64.2 gear inches) and see how that goes.
Otto
#7
Senior Member
Thread Starter
Join Date: Mar 2021
Posts: 1,995
Mentioned: 24 Post(s)
Tagged: 0 Thread(s)
Quoted: 2700 Post(s)
Liked 486 Times
in
351 Posts
So, we spend more W/kg spinning our legs fast than we do spinning them slow. For example, at 110 RPM, the internal work runs about 1 W/kg, which is already significant and it is a sharply increasing function at this point. By comparison it will only be about 0.1 W/kg at 50 rpm.
So, in addition to protecting knees from greater forces and strain, you will also work your body somewhat harder at a higher cadence (for the same actual speed on the bike).
Otto
Likes For LarrySellerz:
#8
Habitual User
Join Date: Jan 2020
Location: Altadena, CA
Posts: 7,986
Bikes: 2023 Niner RLT 9 RDO, 2018 Trek Procaliber 9.9 RSL, 2018 Storck Fascenario.3 Platinum, 2003 Time VX Special Pro, 2001 Colnago VIP, 1999 Trek 9900 singlespeed, 1977 Nishiki ONP
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 4946 Post(s)
Liked 8,087 Times
in
3,826 Posts
What singlespeed riding has taught me...
You're always in the wrong gear. Deal with it.
You're always in the wrong gear. Deal with it.
__________________
"Swedish fish. They're protein shaped." - livedarklions
"Swedish fish. They're protein shaped." - livedarklions
Likes For Eric F:
#9
Full Member
Join Date: Aug 2018
Posts: 303
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 99 Post(s)
Liked 115 Times
in
78 Posts
My bike is a road bike fixed with flip flop, set up as 42 x 18/16.
42 x 18 is good all round ratio for on and off road, speed control without braking or skidding, and good for short bursts of up to 28 mph or even 30 mph downhill.
42 x 16 is easier on the downhills, bit less acceleration, not so good off road or up hill.
On a 700c x 28mm, these are not especially low gears. I find myself doing similar average speeds to what I achieve on my 2 x 10 although admittedly that is heavier and less aero.
42 x 18 is good all round ratio for on and off road, speed control without braking or skidding, and good for short bursts of up to 28 mph or even 30 mph downhill.
42 x 16 is easier on the downhills, bit less acceleration, not so good off road or up hill.
On a 700c x 28mm, these are not especially low gears. I find myself doing similar average speeds to what I achieve on my 2 x 10 although admittedly that is heavier and less aero.
#10
working on my sandal tan
Join Date: Aug 2011
Location: CID
Posts: 22,629
Bikes: 1991 Bianchi Eros, 1964 Armstrong, 1988 Diamondback Ascent, 1988 Bianchi Premio, 1987 Bianchi Sport SX, 1980s Raleigh mixte (hers), All-City Space Horse (hers)
Mentioned: 98 Post(s)
Tagged: 0 Thread(s)
Quoted: 3871 Post(s)
Liked 2,568 Times
in
1,579 Posts
42/18 is the winter gear on my FG. Usually by this point in the season I've changed it to 45/16, but I haven't gotten around to it yet.
Spin it smoothly at 25+ MPH and people won't be laughing at you, they'll be impressed.
Spin it smoothly at 25+ MPH and people won't be laughing at you, they'll be impressed.
__________________
RUSA #7498
Originally Posted by noglider
People in this forum are not typical.
Last edited by ThermionicScott; 07-21-21 at 12:41 PM.
Likes For ThermionicScott:
#11
Clark W. Griswold
Join Date: Mar 2014
Location: ,location, location
Posts: 13,519
Bikes: Foundry Chilkoot Ti W/Ultegra Di2, Salsa Timberjack Ti, Cinelli Mash Work RandoCross Fun Time Machine, 1x9 XT Parts Hybrid, Co-Motion Cascadia, Specialized Langster, Phil Wood Apple VeloXS Frame (w/DA 7400), R+M Supercharger2 Rohloff, Habanero Ti 26
Mentioned: 54 Post(s)
Tagged: 0 Thread(s)
Quoted: 4355 Post(s)
Liked 3,994 Times
in
2,665 Posts
If the kids are laughing at you, you should take it deeply to heart and internalize it heavily.
To those who are looking for serious help and wondering about gear ratios, ride whatever works for you and don't worry about anyone else. It doesn't matter what anyone else rides, it just matters what works best for you and your situation. 42/18 56/15 38/24 or anything in between or outside of that so long as it works well for you.
To those who are looking for serious help and wondering about gear ratios, ride whatever works for you and don't worry about anyone else. It doesn't matter what anyone else rides, it just matters what works best for you and your situation. 42/18 56/15 38/24 or anything in between or outside of that so long as it works well for you.
Likes For veganbikes:
#12
Senior Member
Thread Starter
Join Date: Mar 2021
Posts: 1,995
Mentioned: 24 Post(s)
Tagged: 0 Thread(s)
Quoted: 2700 Post(s)
Liked 486 Times
in
351 Posts
From talking to people I see on the road it sounds like this is actually a smart training method to up my cadence. Think I might get another single speed to ride in a huge gear for strength training. While training to become a fixie monster I was mashing with a 48x14, not sure how effective grinding in that gear is for training, but I met another dude who said he used to train like that. is grinding on a gear that you can't even spin kind of pointless?
Last edited by LarrySellerz; 07-21-21 at 10:56 PM.
#13
Senior Member
Join Date: Jul 2008
Location: Minas Ithil
Posts: 9,173
Mentioned: 66 Post(s)
Tagged: 0 Thread(s)
Quoted: 2432 Post(s)
Liked 638 Times
in
395 Posts
My Swobo Accomplice came with a 42x18. It's a commuting gear. It was my first SS and after a couple of rides I ordered an S300 crankset with a 48T and it's good, my average speed is about the same as on my geared bikes on solo rides. I don't take it on group rides, the gearing would be a little too low for that pace.
#14
Cheerfully low end
Join Date: Jun 2020
Posts: 1,978
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 646 Post(s)
Liked 1,044 Times
in
667 Posts
I did the change to 42/17 on the RockHopper. It works fine. Same overall speed. Easier on the knees. Not entirely used to the higher cadence but I’ll stick with it. I reckon it will grow on me.
Otto
Otto
#15
Guest
Join Date: Sep 2020
Posts: 2,888
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 1346 Post(s)
Liked 3,270 Times
in
1,439 Posts
42 X 18 isn't "crazy low," and if you're even considering what the "fixie kids" will think, you should definitely finish high school.
Fixed gear bikes need bigger gears so you don't spin out on the downhills, but they climb like crap. Lower-geared singlespeeds are much more versatile, IMO.
I live where there are hills, so my SS bikes are 39 X 17 (700c), 40 X 18 (27.5"), and 38 X 16 (26"). I ride with geared riders every week and can keep up just fine.
Fixed gear bikes need bigger gears so you don't spin out on the downhills, but they climb like crap. Lower-geared singlespeeds are much more versatile, IMO.
I live where there are hills, so my SS bikes are 39 X 17 (700c), 40 X 18 (27.5"), and 38 X 16 (26"). I ride with geared riders every week and can keep up just fine.
Last edited by Rolla; 07-22-21 at 07:32 PM.
Likes For Rolla:
#16
Brown Bear, Sqrl Hunter
What are you "training" for? How hilly is your area? Do you actually care if the "fixie kids" laugh at you?
#18
2k miles from the midwest
Join Date: Feb 2005
Location: Washington
Posts: 1,964
Bikes: ~'75 Colin Laing, '80s Schwinn SuperSport 650b, ex-Backroads ti project...
Mentioned: 18 Post(s)
Tagged: 0 Thread(s)
Quoted: 525 Post(s)
Liked 931 Times
in
446 Posts
That was my typical gearing when I was commuting fixed. 14 miles each way, ~800ft climbing. Max rpm on downhill, as calculated by gps speed was 220.
Likes For Dylansbob:
#19
The dropped
Join Date: Oct 2018
Location: Columbus, OH
Posts: 2,144
Bikes: Pake C'Mute Touring/Commuter Build, 1989 Kona Cinder Cone, 1995 Trek 5200, 1973 Raleigh Super Course FG, 1960/61 Montgomery Ward Hawthorne "thrift" 3 speed, by Hercules (sold) : 1966 Schwinn Deluxe Racer (sold)
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 1739 Post(s)
Liked 1,014 Times
in
696 Posts
#20
Senior Member
Thread Starter
Join Date: Mar 2021
Posts: 1,995
Mentioned: 24 Post(s)
Tagged: 0 Thread(s)
Quoted: 2700 Post(s)
Liked 486 Times
in
351 Posts
I hurt my leg today trying to keep up with a group ride, we were going like 25+ on a slight downhill and I was spinning so fast I managed to pull something in my upper thigh/groin. This sucks, since when do you get injured by spinning fast. This bike is a tad small I wonder if that's the reason.
i mention the fixie kids because I am inversing them by riding a smaller gear than I am comfortable with. They all ride in too big of a gear. I'm training to be able to finish the drop rides
i mention the fixie kids because I am inversing them by riding a smaller gear than I am comfortable with. They all ride in too big of a gear. I'm training to be able to finish the drop rides
Last edited by LarrySellerz; 07-23-21 at 09:31 PM.
#21
Clark W. Griswold
Join Date: Mar 2014
Location: ,location, location
Posts: 13,519
Bikes: Foundry Chilkoot Ti W/Ultegra Di2, Salsa Timberjack Ti, Cinelli Mash Work RandoCross Fun Time Machine, 1x9 XT Parts Hybrid, Co-Motion Cascadia, Specialized Langster, Phil Wood Apple VeloXS Frame (w/DA 7400), R+M Supercharger2 Rohloff, Habanero Ti 26
Mentioned: 54 Post(s)
Tagged: 0 Thread(s)
Quoted: 4355 Post(s)
Liked 3,994 Times
in
2,665 Posts
Cool story, I guess?
Again for those who actually need help, don't ride a bike that is too small I know it might seem cool or you are aero, bro but in the end get a bike that fits. You don't save money buying a smaller bike and if you are looking to save weight maybe drink one less beer or take a dump before you ride or both or buy a nicer bike.
Brokie Kids for life!
Again for those who actually need help, don't ride a bike that is too small I know it might seem cool or you are aero, bro but in the end get a bike that fits. You don't save money buying a smaller bike and if you are looking to save weight maybe drink one less beer or take a dump before you ride or both or buy a nicer bike.
Brokie Kids for life!
#22
Brown Bear, Sqrl Hunter
I hurt my leg today trying to keep up with a group ride, we were going like 25+ on a slight downhill and I was spinning so fast I managed to pull something in my upper thigh/groin. This sucks, since when do you get injured by spinning fast. This bike is a tad small I wonder if that's the reason.
i mention the fixie kids because I am inversing them by riding a smaller gear than I am comfortable with. They all ride in too big of a gear. I'm training to be able to finish the drop rides
i mention the fixie kids because I am inversing them by riding a smaller gear than I am comfortable with. They all ride in too big of a gear. I'm training to be able to finish the drop rides
If you're a new rider, and they've been riding for a while, there isn't a magic gear ratio that will give you the base miles/fitness. Gear inches is very much preference. If you can't spin, then get a heavier gear. It will be harder to climb with and will be rougher on your knees.
Likes For Jaytron:
#23
Senior Member
Thread Starter
Join Date: Mar 2021
Posts: 1,995
Mentioned: 24 Post(s)
Tagged: 0 Thread(s)
Quoted: 2700 Post(s)
Liked 486 Times
in
351 Posts
Cool story, I guess?
Again for those who actually need help, don't ride a bike that is too small I know it might seem cool or you are aero, bro but in the end get a bike that fits. You don't save money buying a smaller bike and if you are looking to save weight maybe drink one less beer or take a dump before you ride or both or buy a nicer bike.
Brokie Kids for life!
Again for those who actually need help, don't ride a bike that is too small I know it might seem cool or you are aero, bro but in the end get a bike that fits. You don't save money buying a smaller bike and if you are looking to save weight maybe drink one less beer or take a dump before you ride or both or buy a nicer bike.
Brokie Kids for life!
#24
Clark W. Griswold
Join Date: Mar 2014
Location: ,location, location
Posts: 13,519
Bikes: Foundry Chilkoot Ti W/Ultegra Di2, Salsa Timberjack Ti, Cinelli Mash Work RandoCross Fun Time Machine, 1x9 XT Parts Hybrid, Co-Motion Cascadia, Specialized Langster, Phil Wood Apple VeloXS Frame (w/DA 7400), R+M Supercharger2 Rohloff, Habanero Ti 26
Mentioned: 54 Post(s)
Tagged: 0 Thread(s)
Quoted: 4355 Post(s)
Liked 3,994 Times
in
2,665 Posts
That is a large amount of money. Not for a bike for a bike it can be rather cheap but for something rather useless to you it is expensive. Get something that fits sell this one or strip it for parts if the parts are decent (which for $150 probably not) and buy a frame that fits you better.
#25
Senior Member
Join Date: Sep 2012
Location: SoCal
Posts: 1,186
Bikes: 2016 Surly Cross Check, 2019 Kona Rove ST
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 284 Post(s)
Liked 313 Times
in
211 Posts
Man, I guess I'm at the "really crazy low" end of the spectrum on my ss Cross Check. It's currently running 38x19 (700c x 40 tires). But I ride it like a ss MTB here in the SoCal mountains, so it's all a trade-off. I can clean most singletrack and fireroad climbs I frequent, but I sure do coast a lot elsewhere!