I don't ride brakeless. I'm at 46 x 18 - which is spinny most of the time except when I'm climbing. Hills here are not huge - just rollers. I start the bike with my body weight as well. Given all those things, is it likely that my knees will suffer? I'll go to 42 x 18 if anyone things that'd be better. I'd rather be spinny and safe than mashy and regretful.

46/18 is a really good gear to spin with. Id say that 42/18 is going to be to low. You will not like it on the flats or downhill at all. Id suggest stick with the 46/18 for now.

I ride 52/16. It makes the climbs a little torture some but its a really nice gear otherwise. I did experience knee pain but found out it was just an adjustment in my cleats.

Gearing will not hurt your knees, a bad bike fit will.

I quit riding fixed when I got laid of back in January, but I rode 42-18. My knees would act up if I went much higher than that on the flats and agony going uphill. My cadence on the flats was around 120rpm and I could spin up to about 160rpm. My commute had 400ft of elevation chance, so I would drag my front (disc) brake a bit going down.

I just built up a bike for a trip to Portland that ran the same gear range and found it perfect for myself on around that flat town. My spin was about the same, but I'm out of practice on my skidding. I'm thinking it might be time to stop riding the gearie...

+1

Most knee issues are due to bike fit issues. Even for older and/or heavy riders.

49x16. over 40. Great bike fit. If I spend time off the bike then the first time back the knees don't like it for a time. Brakeless. They only complain for a short time.


Use it or lose it.

Actual evidence of this?

Yeah, I'm 37 and weigh well over 200lbs. I ride more miles than most. I train and race on bikes 5-6 days a week.

Improper seat height/placement is the reason for knee problems, as well as pedaling technique. Gearing has nothing to do with it. Years of my experience and any other fitter is evidence.

But is it true that a lower gear (thus, spinning) promotes elasticity in the knees? (I remember hearing about this in another thread a while back.)

Maybe but I can tell you the only time I ever had knee/leg pain was when I was spinning high rpms but with my seat too high and the high rpms were making it worse as that meant more repetitions of an irritating range of motion...

I'm 55 and do most of my miles on fixed gear (46 x 17). No big hills here; just a couple short, steep ones but I haven't had problems with my knees yet.

I'm about to be 44/16 from 48/16, which is a little higher GI than yours. I feel like 48/16 wasn't letting me spin enough, most of my commute to school is uphill, I hope it's alright.

I'm calling bs on this.

vw addict is right.

Think about it, when a road rider has issues with his knees, no one suggests, "Stay out of your 53t chain ring" as a solution.

Depends on what forum

I'm sure there are other place on bikeforums where people would hear 53t chain ring and say aha there's your problem.

Anyways it seems like all you hear these days is keep rpms up at all times or your knees will explode. Doesn't mean it's necessarily right, but...

To me it is simple, overstressing your knees by trying to push a monster gear is bad...

You think that mashing up a hill with a moster gear and 30rpm is the same on your knees as cruising up on a lower gear and say 70 rpm?

Your body will tell you what you can and can't do. A gear I can push up a 8% grade may kill someone else, so basically listen to your body.

Guys, if we take any statement to it's extreme, it can be bad. For example:

[Person A] "Drink water"
[Person B] "But, you can die from drinking too much water."

If you guys don't take words out of context or to an extreme, then it will all make sense.

but this is bikeforums, everyone has to be right.

spinning with a bad fit is worse than standing up and mashing.

I guess this is as good a place to ask as any, as it's fairly on topic. I'm looking to switch out chainrings as my current set up is too steep for my area and level of conditioning. Trouble is I'm not sure how drastic of an effect going from my current 48t (16 rear) to something like a 38 or 40 would be.

How much of a difference would a drop like that make? Speak slowly, I'm new and stupid

I agree.

A bad fit is a bad fit and it might manifest itself as pain or irritation no matter what gear is used.

Some people are young and malleable enough that they don't notice when things aren't aligned properly. I have a friend who doesn't care how her no-float cleats are placed on her shoes. She says that she can't feel the difference. I, on the other hand, am the Princess and the Pea when it comes to bike fit.

48/16 is considered by most to be "high" for street use. It's cheaper to buy cogs than chainrings. Buy an 18t cog and you should be set.

48/40 = 1.2 => your 48 is 20% higher/harder than the 40.

Edit: Also 40/16 is about equal to 48/19...