# 45/18 ratio, what kinda ride?



## Xiorell (4 Jun 2011)

I'm still a bit lost on all this gear ratio stuff. On a SS with a 45t chainring and 18t freewheel, what kinda riding is it gonna be alright with? I know it does depend on rider but I'm talking generally here. With this ratio are hills generally gonna be a bit killer?


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## gaz (4 Jun 2011)

That is about 67.5 inches per rotation of the pedal. Or at 100rpm it's around 20mph.
Can you get up hills. There is only one way to find out!


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## Bensbikespares (4 Jun 2011)

|Whats your Wheel size 

Front chain ring (45) Divide by freewheel (18) = 2.5 so 2.5 x your wheel size so say if its 26" it will be 26 x 2.5 =65

the higher the number the quicker (speedwise) it will go

The lower the number the better acclertaion it will go


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## Scruffmonster (4 Jun 2011)

I ride a 50/18 and it's fine. The hills around here are for the most part v.steep/short or steep/long and I've not had a problem yet.

That's SS though, not fixed. I dont know if I'd say the same if I couldn't coast the downs...


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## Alien8 (5 Jun 2011)

That's a pretty much run-of-the-mill ratio verging on the low side - but you know already that you really need to give it a go and see what suites you. I run 48/16 which gets me over the mountains in the fens.


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## alecstilleyedye (7 Jul 2011)

46 x 18 is quite versatile ime, if a little spinney on descents…


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## fossyant (7 Jul 2011)

I use 46 x 16 which is about 77.5" and it gets me up hills OK - Well so long as they aren't more than 1 in 10.


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## yello (7 Jul 2011)

Depending on where you live, I reckon that's a fairly safe gearing.

I rode 48x18 (70") around London no problems, and in the home counties without any major problems. I changed to 48x20 (63") around where I live now because it's lumpy, without being mountainous, and 70" was a little too much of an ask.

Edit: I note you're not fixed so spinning out won't be an issue for you.


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## brockers (7 Jul 2011)

I stick 42/18 on for winter (63'') cos it's surprisingly lumpy around NW Kent, and 42/16 for summer as my general utility gear. I actually find that a bit high, and I think I'll be splitting the difference and going for 42/17 on my new build. I'm getting to the age where I have to start thinking of my knees!


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## tyred (7 Jul 2011)

46/18 user here in a reasonably hilly area. Works perfect for me. When you only have one gear, there always have to be some compromises.


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## spybot (7 Jul 2011)

brockers said:


> I stick 42/18 on for winter (63'') cos it's surprisingly lumpy around NW Kent, and 42/16 for summer as my general utility gear. I actually find that a bit high, and I think I'll be splitting the difference and going for 42/17 on my new build. I'm getting to the age where I have to start thinking of my knees!



42x17 is my favourite too...a 17t is also great for skid patches. (If you're into that kind of thing...)

I've tried other gearings, mostly 75" with 42x15 on a long flat ride to clacton at the end of last summer. It was good to that, but towards winter I found it really ground me down up the odd incline - even the small ones around SE London (Brockley etc).

Clearly I like to spin...


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## brockers (7 Jul 2011)

spybot said:


> ....even the small ones around SE London (Brockley etc).
> 
> Clearly I like to spin...



Glad it's not just me then. Going over Hilly Fields with a shoulder bag full of shopping is an effort on anything bigger than 63''!


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## Ibbots (9 Jul 2011)

Tried a few ratios on single speed and fixed and settled on 48x18 for my commute, a bit lumpy with one biggish hill. Will probably drop it a couple of inches for Winter, the headwind up the last hill before home is a bit of a drag.


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## rustychisel (11 Jul 2011)

yup, perhaps a trifle spinny as mentioned, depending on you/where/what for

Me, currently on 48 x 18 = 30kmh on flat roads for as long as I like.


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