Single speed gearing

[BikerB]

I have looked at the "official thread"and noticed people seem to run smaller front rings..32
I had a ride out the other day,a couple of hills,the ratio i found that was good is 42/17.
Is there an equivalent using a smaller front ring?

 

[kipperthedog]

Re:

http://www.bikecalc.com/gear_ratios

Should find it for you.....make sure you enter the correct wheel size though.

 

[mattr]

On of off road, fenlands or peak district?

All makes a (big) difference.

 

[hamster]

42/17 is a very common setup for a road singlespeed. However I suspect that you would struggle offroad.
Offroad tends to be around 2:1, so 32/16. This makes a good starting point, although as mattr says a huge amount depends on where you ride.

 

[BikerB]

Thanks for the help ,it mainly for towpaths and a few light hills.
I have a geared bike for the rough stuff..

 

[one-eyed_jim]

32:13 is close, as is 37:15

42/17=2.471
37/15=2.467
32/13=2.461

 

[02gf74]

Re:

Unless you are a top professional cyclist, if you can get up hills with 42/17, they cannot be hills.

 

[FluffyChicken]

Re:

If you hadn't gathered you just do a little mathematics.

42 ÷ 17 = 2.47

Then you just work up from the rear cog size and times by 2.47 and see which front cogs fit

11x2.47
12x2.47
Etc
Assuming you can run 11 and 12 as single speed, most start at 13.

But why bother if what you have works for you? You have more chain overlap so the setup should last longer

 

[mattr]

That's one reason track riders tend towards bigger rings ands sprockets.

Less friction, less wear. (Plus they can fine tune the ratios much more effectively)

 

[JamesM]

Thanks for the help ,it mainly for towpaths and a few light hills.
I have a geared bike for the rough stuff..

Why do you want to change to a smaller front ring? The 32:13 equivalent will wear out quicker and will only have around 6 teath engaged on the rear sprocket.