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Sit bone width
My last few saddles I've had are meant to be correct for my DIY measured sit bone width. (sit on cardboard method) I measure up as narrow, but can't help feeling that I would be comfier on a wider one.
Has anyone found a significant difference between DIY measured width vs bike shop/bike fit width?
Has anyone just decided it didn't work for them and gone for a wider or narrower saddle than recommended?
WTB have a sit bone width calculator based on wrist circumference. It worked well for me & I ended with a wider saddle than I thought I'd need.
Have a look at the SQLab fit measurement system. Basically the more upright you're sat - most likely on an mtb, cargo bike, tourer etc - the wider your saddle needs to be because your pelvic tilt changes and you then sit on a different part of your sit bones. I ride a 130mm saddle on my gravel bike, but 140mm on mountain bikes. That might explain why your 'correct' sit-bone width feels too narrow, possibly.
I'm correct for a 143mm Specialized but use a 152 or whatever it is and find it splendid.
WTB have a sit bone width calculator based on wrist circumference
Does it still work if I can't get my hand all the way in?
Does it still work if I can't get my hand all the way in?
Bloody brilliant! Well done.
Posted by: OnzadogDoes it still work if I can't get my hand all the way in?
Bloody brilliant! Well done.
Yes indeed, I wish I was that quick 👏
I run an SQlab 611 14cm having done a home cardboard and measure and been OK so far but when I went to a show they were there and doing measurements - came in at 15cm.
Was very dubious but trusting of SQ as had them for ages and bought a 15cm new to me off ebay and (much to my surprise) can feel / tell the difference.
It is exactly the same model / year saddle so otherwise unchanged.
James
Interestingly, bike fit James on YouTube has very strong options on this and says generally people end up with saddles that are too wide. If in doubt, go down.
I'd got with what @onzadog said as my 14cm was fine, until I got measured and tried the 15cm equally fine, but a little more comfortable at the back of the saddle on 4 hour plus rides. Of course all asses are different 🙂
Yeah, although James is a bit marmite I think most of what he says (inc. about saddle width) makes sense. Probably the best way to find the right saddle is to go to a bike fitter like him that has a pressure mapping saddle cover and a load of saddles to test, that will show where your sit bones are actually resting and any other pressure points that you might need a different saddle shape to address. Not cheap though...
Posted by: OnzadogInterestingly, bike fit James on YouTube has very strong options on this and says generally people end up with saddles that are too wide. If in doubt, go down
Interestingly, if you go back to some of his older videos, he's quite often changed his mind quite markedly over the space of a year or two over what does and doesn't work. All of which is fine, but doesn't fill me with confidence over whatever he's suggesting this week. Mostly - and entirely reasonably - he's about getting a good bike fit to nail the basics. And pointing out that a lot of saddle discomfort is down to poor fit and often, seat height being set too high.
On the using different width saddles. I ride a 130mm SQLab saddle normally but was given a couple of 140mm ones by a mate. I can ride the wider saddle okay and on my upright hardtail it's arguably better, though on a gravel bike, the extra 10mm seems to mean I'm more likely too rub occasionally on the edges of the saddle.
Basically the more upright you're sat - most likely on an mtb, cargo bike, tourer etc - the wider your saddle needs to be because your pelvic tilt changes and you then sit on a different part of your sit bones.
I can see the logic, although I'd suggest that 90% of people don't adopt a particularly aggressive roadie position. People who actively race maybe but the other 99% who just do club runs, audaxes, etc just sit up in the same sort of position as MTBers. I only find I need a different saddle when sat completely upright. For the most part I've always used the same saddles on/off road, although offroad I can usually get away with a less optimum saddle as I use it less so it's where the 'almost fits but too expensive to stomach the loss of selling it' saddles go to die!
Just ordered a Selle Italia X(something) to try. Apparently it's flatter across the back than an SLR so should in theory offer better support to the hips if you don't naturally rock, and my hypothesis is that your hips only rock if the saddle is too high so it might be perfect for the off-road where the saddle is frequently lower than full extension.
I can see the logic, although I'd suggest that 90% of people don't adopt a particularly aggressive roadie position. People who actively race maybe but the other 99% who just do club runs, audaxes, etc just sit up in the same sort of position as MTBers.
This. I'm on the med/wide ass border according to Spesh, so I went up on my road and gravel bikes. No complaints on a Spesh BG saddle
Well that's a turn up for the books, the WTB wrist measurement thingy gives me a measurement of 144mm and the Spesh Body Geo measurement gave me a width of 143mm, I ride Spesh 143mm or Prime 143mm short nose saddles on all my bikes
According to my right wrist measurement I'm a 180 wide saddle but only 120 for the left one. I don't know what that is trying to tell me...🤪
Started this season on a Selle Model X - first tours were kind of highway to hell 😬
Just a minor adjustment maybe 1.5 cm to the front an lowered also ca 1-2 cm and it’s all fine now 👍 I thought I would never get used to it..