I have a 36T front ring and am wondering if an 18T would be a good pairing on the back? In the past I have run 32/16 and was wondering what the difference will be?

Its exactly the same…

32/16 = 36/18 so you won't notice much diffference at all…..except maybe a teeny tiny little bit less wear as there are more teeth to spread the load

just an ever so slightly heavier way of achieving the same ratio.

Thanks for the quick responses guys.

I have gone to a 34/17 because I find big rings seem to roll better, maybe because the chain bends less than arround smaller rings

but small rings offer more BB clearance 😀

I like 36/19 (but I'm quite old).

I use 44 /20 because it was what I had lying around

I use 32:17. Because 17 is a prime number, it means that the chain will load on a different tooth every time round and when coupled to the 32T front that is further extended so the chain to chainring to sprocket arrangement only comes round every 32 X 17 = 544 revolutions. At a s/speeding cadence of 75 (averaging out 30 on the climbs and 120 on the downhills) that means the same combination arises only once every seven minutes and 15 seconds (assuming no freewheeling), or put another way for a 26" wheel every 1233 yards (ditto).

If you do the same maths for 32:16 (or 36:18, they're the same 2:1) the combination will recur every 32 revolutions (36 for 36:18) hence the chain and sprockets will wear 544/32 = 17 times faster on 32:16 compared to 32:17

Either that or Brant was out of stock of 16's when I last bought one?

bloody hell my head almost fell off with that last post

But I can hear where you are comming from sort of

I think that setup is what we used to call a hunting tooth.

34:18 because those were the parts in my spares box at the time I built it…

38:16 on the cx bike nice balance for both on and off road. Thats how it came.

It may change to 44:18 fixed when the weather gets better and use more for road duties but again only because thats what I already have as i know its not a huge gear difference