- 31.8 mm vs 35mm bars who will win?
Will one standard eventually be abandoned? I’m getting a new stem and bars and don’t want to end up with an old standard.Posted 2 months ago
I suspect 35mm will win for no good reasonPosted 2 months agoGaz.dickSubscriber
Will it ruin your ride if you do end up with old standards?
Get what is pretty/cheap/strong (insert requirement here) and enjoy 🙂Posted 2 months ago
I’m still buying 31.8mm and I suspect they’ll be available for a long time yet.
Not a “standard” to fret about IMO.Posted 2 months agoscotroutesSubscriber
I have one bike with 35mm, just because it came like that. Will likely be going 31.8 on it as the sweep I want isn’t available in the larger diameterPosted 2 months ago
What’s wrong with ending up with an old standard? If it works functionally, what difference does it make?Posted 2 months ago
I have gone from 35mm to 31.8 last month and despite 20mm wider bars, the torsional rigidity seems identical, ie extremely high. The bars are 19g heavier though.andytherocketeerSubscriber
Will it ruin your ride if you do end up with old standards?
Yeah, 26″, 27.2mm, 25.8/26.0mm all stopped working, as did anything with a front mech, or an angle steeper that 63deg 😉
Not sure if it’ll be the clamp diameter or the whopping 60mm length (for a frame designed for 70mm) that’ll be the cause of mine to be no longer usable. 😉 Had to change the extra wide bars to what are now too narrow, but are 50mm wider, else the bike would have been unrideable.Posted 2 months agohols2Member
33.4 mm seems like a sensible compromise.Posted 2 months agoroverpigSubscriber
35mm has been around for quite a while now but doesn’t seem to be gaining much traction, so I’d stick with 31.8mm for now. But it’s not my money of course 🙂Posted 2 months agoJonEdwardsMember
Being at the skinnier end of the spectrum, I’ll be trying to stick with 31.8 for as long as possible. I’ve yet to hear anybody say anything actively “good” about 35mm, and there seem to be a few manufacturers (Hope and Oneup) come to mind claiming to be making 35mm bars that are “as comfortable as 31.8” (so why not just use 31.8??). It feels like a “standard” for the sake of selling MOAR STUFF!!
Anecodtally – I ran a 660×25.4mm carbon Monkeylite on my hardtail for ages, then having got used to wider bars on my full sus, swopped for the identical 685×31.8 version. It was horrible in comparison – no yield or damping in it at all. I was genuinely shocked at how much difference it made.Posted 2 months ago
25.4 is still working fine for me 🙂Posted 2 months ago
“as comfortable as 31.8”
Yep, I’m mainly sticking with it for this reason, but also for my existing Garmin and light mounts. And because I never change a stem and bar at the same time.Posted 2 months ago
I’m currently running a 31.8mm Hope AM stem with 35mm length and an 800mm 50mm rise Spank Spike Vibrocore bar.
I wanted to try the 820mm wide Vibrocores for the extra width. They only come in a 35mm clamp and the rise is only 25mm, so I was going to get a little rise back by changing my stem.Posted 2 months agoP-JaySubscriber
I think they’ll probably coexist for years more at least. 25.4 was still around for years wasn’t it?Posted 2 months ago
What’s wrong with ending up with an old standard?
In the case of my >20yr old road bike it’s 1” steerer and 26.4mm (I think) clamp are seriously hindering my desire for a change of stem without the cost snowballingPosted 2 months ago
I wanted to try the 820mm wide Vibrocores for the extra width.
What grips are you using?
DMR Deathgrips add a bit of width, so my 780mm bar now measures 800mm.
Just sayin’.Posted 2 months ago
1” steerer and 26.4mm (I think) clamp are seriously hindering my desire for a change of stem without the cost snowballing
So you can fit a new stem for as little as £6, which I’d say isn’t quite “snowballing” 🙂Posted 2 months ago
You are right Bez, it’s just the inertia of collecting all the bits and worrying about the steerer shim being an OK solution/fitting the depth of the stem OK.
convert it from a quill, if you have a threaded headset
If it were threaded/quill I’d just hoist it up and be happy, the even older standard would have worked better for me!Posted 2 months ago
Stem are very very cheap as far as I can see. I had to spend all of £14 for a new 31.8 50mm Nukeproof stem. I sold my old one for £19. Some snow balling…Posted 2 months ago
I suspect 31.8. When Renthal released their 35mm stuff they didn’t even say it was lighter/stiffer/stronger, they said both were made to the right level of stiffness and equal strength, IIRC the 35mm came out a touch heavier but accidentally farting on it probably makes more difference to the weight.Posted 2 months agojoefmMember
It’s not being adopted across all the bike manufacturers so for once it seems even they think there’s no difference or they offer the rider a worse ride as they’re too stiff.Posted 2 months agoNobeerinthefridgeMember
I honestly couldnt tell you what diameter my bars are!
35mm seems a bit like 29ers, heavier for no real world benefit. 🤔😁Posted 2 months agoAkersSubscriber
I just choose on the shallow basis of aesthetics. To my eye 35mm looks better on fat tubed carbon frames while 31.8 bars look best on slimmer steel and Ti tubed frames.Posted 2 months ago
I’m using the spank 33 grips which are super long. I tried the fatter Deathgrips but they are too short and too hard for me. If they were mushroom all over I’d like them better, and about 10mm longer.
My spank grips add about 10mm either side as did the SC Palmdales which I also liked. I’d love a palmdale that wasn’t tapered in towards the bar.
If Oury grips where 20mm longer I’d be very happy also.
Ideally I want a 1000mm bar that I can cut down until I like it. 800 just feels too narrow.Posted 2 months agoratherbeintobagoSubscriber
Ideally I want a 1000mm bar that I can cut down until I like it. 800 just feels too narrow.
Wasn’t someone doing a yard-long bar?
For most riding, I’d be pretty sure 35mm is aesthetics; presumably there is a stiffness benefit (or a weight benefit for the same stiffness) but would anyone actually notice in the real world?Posted 2 months ago
presumably there is a stiffness benefit (or a weight benefit for the same stiffness)
If it were to be a bar with no clamp, yes.
In reality, you end up getting local deflection of the bar around the clamp, which will become significant (or add significant weight to avoid) once the diameter reaches a certain point.
e.g. imagine holding a metal cup, then imagine holding a coke can – the wall just folds in as you squeeze on the latter. (more comparable, if you took small enough diameter tube made out of coke can you wouldn’t feel any give when you squeezed it).
Edit – don’t know why I didn’t say it first but the real solution is 1 piece bar and stem for both weight and stiffness. But pricey/limited choice/limited adjustability.Posted 2 months ago
31.8 bars, 35mm stem + shim. All the bases covered then.
I think they’ll probably coexist for years more at least. 25.4 was still around for years wasn’t it?
Kinda, although new bikes swapped pretty much straight away as it was both lighter and stiffer (both of which were good things). And aftermarket stuff seemed to change pretty quickly. I bought some 1″ bars years later, but they were bottom of the range and described as “oversized” which I assumed meant 31.8 but didn’t and CBA sending them back as i had a stem that would fit them.
35mm on the other hand has been around for years and doesn’t seem to have become the default, especially away from #enduro.Posted 2 months ago
Sounds like you’re way ahead of me OP.
Out of interest, are you really lanky/orangutan armed?Posted 2 months agokelvinSubscriber
My favourite bars are 35mm… but it looks like any manufacture can produce whatever they want with either clamp size, so we might as well stick with one or the other. Don’t care which. But no need for both.Posted 2 months agoreggiegasketMember
I’m more fussed about sweep, rise and suppleness.Posted 2 months agoretro83Member
31.8 and 35mm are boring. I want somebody to bring out 33.4.Posted 2 months ago
Almost as laterally stiff as 35mm with the vertical compliance of 31.8.ta11pau1Subscriber
35mm is so 2019, its all about the 36mm bars now…
Posted 2 months agoprezetMember
I think they’ll both remain. 35mm seems to work better for carbon bars where they can be made lighter and stronger, and can offset the increase in stiffness by how the layup is done (or playing with shapes like OneUp have done).
31.8 is perfect for alloy bars – some 35mm alloy bars are far too stiff and the extra width has no advantage, but I guess they’ve been created as an alloy version of carbon offerings.Posted 2 months ago
or playing with shapes like OneUp have done
Why’s it taken this long to do what roadies have had for at least a decade? Even the alloy bars on my road bike are shaped.Posted 2 months agosquirrelkingMember
it was both lighter and stiffer (both of which were good things).
Say what you like about the flex but Protapers were fantastically comfortable.
31.8 will be around a while yet I think, 35 doesn’t seem anything like as popular for the length of time its been around.Posted 2 months ago
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