Gear ratios...ULTIMATE noob question
 

Please explain how this works even though I'm sure most is due to personal preference.

I ride 46 x 17 and find I spin out sometimes. If I want just a bit more tension in my pedal stroke, what should I do? Chang the cog, chainwheel, or both?

I would ask this at my one of my LBS's but I live in Philly and most (not all) of the people who work in the shops here are self-righteous *****les who would act snarky and then tell me to check online.

Thanks in advance

You can either increase the size of your chainwheel, or decrease the size of the cog.

Cogs are usually cheaper, so I would recommend you decrease the size of the cog.

Don't go too crazy. Try 15.



Now get ready for a few people to link sheldon's website (or maybe use lmgtfy) because they have nothing else to offer.

46x17 is very reasonable. I think you're better off learning how to spin properly than compensating for a poor spin by increasing your gearing and trashing your knees.

46x17 is a fine all around gear. If you're spinning out on the downhills learn to spin fast or whip skid occasionally to slow your speed down.

Also true, but it depends on when you're spinning out.

If you spin out at 140 RPM, then don't worry about it. You do not need to learn to spin faster than that, ever, for any reason.

If you start bobbing in the saddle at 100 RPM... then yes, you've got problems and need to practice.

140 is pretty low dude. Track racers are easily into the 200+ range with practice, and I can spin 180 going downhill. For a short sprint I can probably crank up to 160 which I think is well within the reach of most cyclists.
And if you can sprint at about 160 rpm, you can run a lower gear for cruising, have more stamina, climb faster and STILL have as fast a top speed as someone who runs a heavier gearing and struggles at 140. When I ran 48x18 on our fast rides I'd beat everyone on the uphills, then on the downhills me and the fastest rider would be hitting 59 kph on the way back down.

please excuse us mere mortals.

See this always comes up when people talk abou spinning, and I think mediocrity has become so entrenched that you guys have a hard time believing that competence on your bike is even possible. It's like saying "yeah right, hercules" when someone tells you they just rode 50 miles on their bike.

If Keirin and other track racers can hit 240+ rpm, and if there isn't likely a single amateur track racer in EXISTENCE ANYWHERE who can't spin 170+ even if they lose every race they enter, why is it hard to believe that an average person can't learn how to be competent on his bike as well

elTwitcho:

The OP doesn't know what a gear ratio is.
I reiterate: he does not need to spin faster than 140 RPM.


What you're saying is like telling a guy hacking at the driving range with rental clubs that he shouldn't be satisfied until he can hit drives 250 yards down the middle of the fairway, because any less is to be satisfied with mediocrity.
I'm saying you're silly, and he's probably better off learning the difference between an Iron and a Wood first.


That said, I should have been more clear. What I meant was:
I, for example, have no interest in racing track backs and thus would never for any reason ever need to spin faster than 140 RPM.

No, I agree, everyone on these forums is constantly talking about "spinning out" and that phrase doesn't really mean what they think it means. Most of the time, the problem is not that they're spinning out that gearing, they just can't spin fast enough.

I still had to call you out for boasting though.

Wait, what does "spinning out" mean if not "the highest cadence you can maintain?"

No gearing has a "spinning out limit" built into it... it is always the rider which limits the maximum cadence.

Well, I did beat 12 messengers out of a field of 25 in my last alleycat... ;)


But I don't see why saying you can't do something now means you should never do it. Like I said, if you can spin faster, you can run a lighter gear while still maintaining a fast sprint speed or downhill speed. That's useful. The faster you learn to spin, the faster your top speed is going to be.

You're telling the guy basically not to bother learning to spin, and instead get a heavy track gear and mash slowly. Aside from obvious knee problems, this is going to guarantee that he's never going to develop a good pedal stroke and he'll ALWAYS be slower than someone who ran a lower gear and can spin faster than him. Forgive me if I'm not understanding you correctly but it seems to me that that advice is basically encouraging bad form to get a small immediate payoff instead of working towards the bigger payoff that will take time to get.

I wasn't telling him to get a big gear and mash slowly, I said to find a gear he's comfortable riding at 100 RPM.

Which isn't slow, and is what most cyclists recommend as healthy.

You recommended a 15 tooth cog, that'd give him 24mph at 100 RPM. If he's comfortable as a newbie just cruising at 24 RPM he'd better start talking to some cycling teams who'd probably be pretty stoked to have him.

46x17 at 100RPM is 21MPH. Personally I don't think that's a bad cruising speed at all and it'd probably put him at being faster than a lot of the people on these boards if he can hold that speed for an hour long jaunt around town.

You're being kinda silly.

He asked a really simple question with a simple answer. I answered it, and you added the caveat that he should probably work on maintaining a faster cadence. I clarified by saying that 100 RPM is a good cadence to shoot for.

There isn't a problem here, except that you want to inform everyone how fast track racers can pedal.

i just switched from 46/15 to 46/17 today and im very pleased with it. haven't done a ton of downhill but i did some sprints and i didnt find myself out of control spinning. stick with 46/17 and learn to control your spin. and if you are still spinning out on downhills put a front brake on.
changing the size of the cog makes a much larger difference than changing the chainring. you'll notice a pretty big difference in two teeth on the rear

I'm currently riding 48x19 because it's a fun gear for me around this time of year. I move through 15, 16, 17, and 19 frequently.

Just based on my own preferences, 46x15 is too much. What you have now is a fine gear, a 46x16 cog is about as high I like to go. I would stick with the current gear and put the 15 or 16 on the other side of the hub, if the hub is fix/fix.
I run 48x19 with an 18 on the other side. Occasionally I'll ride the 18 for the hell of it and for fast group rides so I have slightly a higher top speed.

Not taking sides, I just sincerely like this piece of advice. On that note, is it advisable (not really the word I'm looking for, but it's close) to start at a low gear and work on spin/form then work your way up the GI chart? I'm saying this because, as I understand it (from a newb perspective), it would be easier to begin low as it doesn't require as much strength (but a lot of skill: controlling yourself at high speeds) and as you begin to hone your spin/form you are at the same time building strength that will enable you to be able to push 80+ GIs. Just a curious newb question.

I have to agree with dsh.
Reasons you are wrong:
1. We are not all professional track racers.
2. Most of us aren't Lance Armstrong.
3. The slope in a velodrome (0) is not the same as on the streets.
4. Most of us don't train consistently (so your "average" person can be someone within a wide range of cycling capability) but instead ride to commute, trick (even lower ratio), or for recreation.
5. Your foolish assumption that everyone is "entrenched" in "mediocrity" is senseless; almost all of us realize our own level of cycling, and build our bikes correspondingly.
6. We are aware the gearing of track racers, but since they are racing, professional athletes, and ride in the velodrome and the only thing we have in common is we turn cranks, I hardly think that your little analysis of your "average" cyclist is a plausible answer.
7. Yes, you are right if you are describing the human ability to perform that task of higher gearing is physically possible, but "competence" in your eyes, apparently, is that everyone should be on the same level as professional track riders. So you are assuming that the "average" person should be as fit and fast as those racers? I think not.

Most people I have heard who talk about starting track racing (ie, a structured commitment to going fast on a fixed gear) say to start low, learn to spin, then go with a higher gear when your spin is higher. You build your spin, then work on leg strength.

"reasons you are wrong", that's cute.

I never said the average person should be comparable to a professional track racer, however it isn't unreasonable that a person who rides every day and pushes himself/herself cannot become easily equivalent to a mediocre amateur track racer. There are likely a lot of people riding fixed gears who have never seen a velodrome (be they messengers, serious commuters or just people who like to ride hard) who could likely fit right in to track racing and do ok on an amateur level. There's no reason for you to be so stubbornly committed to sucking.

And lastly;

I'm the one arguing for the LOWER gearing, jesus christ.

el Twicho.

We know you are correct. Well I do at least.

I agree, riding fixed, and if you do it everyday and try to push yourself that you can become a good fast strong rider. One of the benefits of fixed riding was the improvement in spinning ability. At first I sucked, but I focused on controlling my legs and quickly learnt to spin fast. Over time, you get stronger and find that you are ready to move up a gear, then build strength and reach a high candence (along flats) and progress some more.

There is a limit, and it depends on the kind of terrain you have to deal with, but it should mean we are better riders because of it.

Ok you've reiterated this like 5 times and it's a really stupid thing to say.

What do you mean "sucking"? Sucking at what? Sucking at commuting? Sucking at staying fit? Sucking at getting to your friend's house? Sucking at having wind in your face? Sucking at enjoying your bike?

I honestly see you going up to a duffer on the golf course who happily shoots his 100's and telling him he "sucks" and is "entrenched in mediocrity" because he hasn't perfected the 3-iron power fade.

I would say a small minority of people riding bikes give two ****s about racing, and you are saying that ambivalence constitutes "sucking". I'll say it again and it's as true now as the first time I said it: If you don't care about racing, you do not need to be able to spin faster than 140 RPM.

In golf if you don't care about being competitive, you don't need to learn to crush drives 250 yards.

In bowling if you don't care about leagues or tournaments, you don't need to throw a hook.

In pool if you don't care about hustling at the bar, you don't need to be able to hit jump shots or masse.


Spinning at 140+ RPM is an advanced cycling skill, and one that is entirely unimportant for the majority of riders. This does not mean people uninterested in learning this advanced skill "suck at bikes", just that they look for different things in the sport.

yeah, but people get competitive, if it's in the car, on the slopes or on the bike, some people like to overtake other people and own them!

Definitely, on that we are agreed.

If you need to be faster than everyone else, you better learn to spin.