Is it the seated grinding/mashing that knackers your knees? Should I stand for every climb to give them the best chance of surviving?
My new frame is a little bit smaller than i would ideally have – should i also be changing posture to protect my creaky knees?

it’s more likely to be as a result of a badly fitted bike rather than singlespeeding sat down.

Pushing a high torque gear slowly will not inspire your creaky knees. Gear down or get gears.

I dabbled with singlespeed for 3 years or so, before settling on a decent setup that I now use between around November and March. When the trails are minging, it helps a lot to throw my bike straight in the shed rather than spend ages cleaning it after every ride.

Having tried it on 26, 29 and now 27.5er wheels / frames, I’m happiest with the latter (coupled with large-ish tyres and a 29er rigid fork on a Soul 275).

I use 30x16T, which is definitely on the spinny side – but offers great get-up-and-go when needed. (I’m also now running an easy gear on my commute: 39x18T on a 700c-wheeled drop bar bike). I’d rather spin out than get too many creaks, whether they be from bike or body! 🙂

I stand up for singlespeeds (that should be a t-shirt slogan).

Sit down for smoother spinning sections, but as soon as the cadence drops below about 80 it’s time to stand up and mash.

It’s worth training to spin faster rather than mash the pedals harder though, so as your fitness goes up, try and avoid the temptation to put bigger gears on, you’ll always be able to mash a big gear at 30rpm, but with practice 110rpm is achievable and will increase your range.

1×10 with an 11-36 is 327% gear range, 30-110rpm on a SS is 366%.

(misses the obvious point that you can mash or spin gears too, but I think SS trains you to work outside the optimum cadence range so it’s less of a disadvantage than the maths tells you it is)

Hmm. Definitely need to use an easier ratio. My cruising cadence is nowhere near 80 around my local loops.

knees have more or less been fine, I’m quite happy to stand up though. Lower back can sometimes get a wrenching though.

Round here trails are not normally swoopy, flowy smooth but short sharp hills with and end in sight, quite rough too – so happy to have 32:17 (26″) though dabbled with 32:16 when I was fitter. As above, glad to be able to knock mud off the chain, wipe down and put away. Now if I could just upgrade to disc over rim brakes!

Did run a cross-ish bike, that had IIRC 32:15 – had to hop off on trails and was spinny for road, but quite versatile and fun.

Fixed gear dropped bike on MTB frame has 42:14 I think, which can get me up most stuff, average around 15mph on pootle runs..

A while back I asked for some SS advice.

Several posters suggested gearing down and spinning more.

It’s dead flat around and I was sceptical of giving this a bash.

I went from 32/16 to 32/18.

I certainly spin more and generally it’s a set up that works … For now.

So I would rather sit and spin on a proper fitting bike than stand and mash

standing up is better than straining sat down…

I very rarely stand up and use 30/14 in winter and 30/13 in summer (on a 26″)

I have ridden solely single speed for more than 10 years and my knees are fine. Maybe it is all down to experience/adapting to it after all these years but I am able to spin very high and mash slowly

I find that riding a single speed is easier on my knees/back than riding geared bikes, probably because I’m out of the saddle much more. I would say that 75% of my riding is on my rigid SS and most of that is climbing or descending with very little spinny flat stuff, which is perfect. I don’t think the likes of 30:14 would work well around here, 30:18 more like, which is what I’m using on my Hummingbird.

Why were they never more popular, I wonder? As designed ( as a 69er) it’s the best handling bike I’ve owned.

Definitely learn to spin rather than mash – it takes a few years to develop strong tendons and ligaments in your knees so be kind to them.

Just back from the shed – 34:16 is now 34:18. Spinning here I come.

Last year was my first winter single speeding. Ran 32:19 on a 26er. Able to spin on the flats like crazy and just get up long Chilterns hills. Each ride turned into an interval session – painful but a lot of fun.