I used to have a 26lb singlespeed that was rideable with 32:16 around the local hills but which eventually knackered my knees. After a singlespeed rest period I now have a 22lb singlespeed that I’m thinking of running 34:16. Do you think that is about right to balance out the weight saved higher gearing with knee safety? I am trying to get it right first time as changing anything is a bit of a faff (34:16 looks perfect from a chain length point of view too).

Same wheelsize? If so then a 34:16 is going to be harder by about 12% than a 32:16. The weight difference of the bike is hardly worth worrying about as a proportion of the combined weight of you and the bike.

Hmm – yes, same wheel size. I was originally going 34:18 to make life easier but thought a 22lb bike would skip up hills and so thought a higher gearing would be good for the easier bits. If weight makes faff all difference I go back to this.

edit*: your maths is rubbish.

(*as i’m too slow)

a 34:16 is going to be harder by about 12% than a 32:16.

Isn’t it about 6%?

As already mentioned, how much has the weight of bike+rider changed?

a 22lb bike would skip up hills

It will with the right gearing. I’d stick with 32:16 particularly given the previously shonky knees.

Oops 😳 Just read the fraction off. Ratio goes from 2 to 2.125 so 6.25%

Weight of bike and rider has changed by 2% – I didn’t think about it that way. Same or slightly easier gearing it is then (goodbye magic ratio).