PDA

View Full Version : single speed gear ratio


Cecil M
11-21-2006, 05:35 PM
I just ordered a new wheel set and want to switch up my gear ratio. My current gear ratio is 46/16. I am looking for a little easier of a gear. I am sticking with 46 and thinking of getting a 17 tooth freewheel. Will that make a big difference? I am looking for an easier gear to pull hills, but don't want to spin too much.
Is there an effective tool cyclist use to find which gear ratio work best for their needs?

peace

Jonathan Maus
11-22-2006, 10:43 AM
I'm looking for the same info!

My new bike is a 42-16 and it's killing my knees. I live in North Portland so I have a hill to contend with almost every time I ride.

I'm looking at an 18T cog.

This is my first-ever singlespeed so I'm a newbie at all this.

any info would be appreciated.

mizake
11-22-2006, 11:14 AM
I recommend a 44/18 ratio. It won't kill your knees, spins fast enough, and works on hills.

fetishridr
11-22-2006, 01:26 PM
for general riding, most road riders (dudes and dudettes in spandex) ride a 42 18 or around 63 to 65 inches. this allows for 80 to 100 rpms at 15-20 mph.
i ride this for hours on end. you do need to spin like a mofo going downhills, but thats good for you. you shouldnt have knee problems (tendonitis) with this small of a gear.
If you do have to climb, and you ride this bike for more than 20 minutes at a time try to keep the gear ratio around 65 (thats what lance trained on).
this ratio is smaller than what most messengers ride on, but riding an 85 inch gear is for the track, not for traffic.
another plus of the small gear is that its easier to break loose and skid.
if you do like to grind a lot (bad for knees) try 70 inches. i rode a 59 inch gear for a long time for road riding, untill i switched rings. thats like a 39 18. if you want to ride fast (ie speed of traffic) its a little short.
And what are these inches you are speaking of,
a good website is
http://www.fixedgeargallery.com/resources/gearchart.jpg, also check out sheldon browns site (google it)
it will give you all the ratios you can ask for.

tessturbo
12-05-2006, 12:02 PM
I just ordered a new wheel set and want to switch up my gear ratio. My current gear ratio is 46/16. I am looking for a little easier of a gear. I am sticking with 46 and thinking of getting a 17 tooth freewheel. Will that make a big difference? I am looking for an easier gear to pull hills, but don't want to spin too much.
Is there an effective tool cyclist use to find which gear ratio work best for their needs?

peace
I use the gear calc on www.bikeschool.com to calculate gear inches. Formula for the DIY crowd is wheel circumference multiplied by number of chainring teeth, divided by number of cog teeth.

I run a 39 X 16 fixed, about 66 inches, but I'd run lower on a freewheel SS.

And yes, that one single gear tooth difference in the back is a significant change. Tooth number of the cog has a much larger effect on overall gear inch than chainring tooth count.

patrick_barber
01-03-2007, 02:55 PM
i have been riding a fixed gear for about two years now, and here's what I know about gearing.

-- prepare thyself to experiment with some combinations. What works best for you really varies according to your riding style, cargo, terrain, etc. Surly makes a decent, cheap-ish fixed cog that you can afford to experiment with. Shimano makes decent cheap-ish freewheels. And suddenly all those used chainrings start to look pretty attractive.

-- with that in mind, if you get a 1/8" chain, you'll open yourself up to more options w/r/t used cogs, etc, since 1/8" chains work on both 3/32" and 1/8" teeth. You can get an expensive 1/8" chain (the track race kind) or a really, really cheap 1/8" chain (the BMX kind).

-- Every time I lowered my gear, I liked it better than the previous higher gear. I'm guessing this is because the more you ride, the better you'll get at spinning, so the more you'll be able to appreciate a lower gear. I also ride mostly with my partner, who is slower than me, so a lower gear allows us to ride side by side without killing my cadence. Also, I got into climbing some ridiculous hills on my fixed, so a lower gear was a welcome thing... and I got better at spinning, like I said.

My fixed gear bicycle is set up with 42/19, for about 60". I started with a 48/18 (72", I think) and descended from there over the course of about a year and a half.

gabrielamadeus
01-09-2007, 02:15 PM
This is what I've found to be the most comprehensive gear calculator:

http://sheldonbrown.com/gears/


It takes into account wheel size and crank length two other important factors. I had to do some experimenting to find what I like best. (I've forgotten what it was though!)

Also keep in mind many of the replies were about fixed gears, which should be lower than a single speed bicycle.

mizake
01-10-2007, 03:27 PM
It's hard to know who to listen to with so many experts.

Cecil M
01-12-2007, 06:33 PM
Thanks for the help. I did switch to a 46/17. My back stopped hurting the week I switched and I can get anywhere I need to go. Most people I spoke with said they have collections of cogs and chain rings from all the ratios they have had. I guess with all the formulas and calculations it really depends on the riding you do and how your body responds.

peace