A look at the trends in MTBing over the last 10 years and how they've affected the weight

[TheRookie]

Based on the 'evidence' (yes it's not conclusive) of the relative performance of 27" diameter wheels (called 27.5) versus the 28.5" (called 29 - both nominal based on a 2" tyre), I would say it's unlikely a larger wheel will be faster, in fact the optimum (if such a thing can be said to exist given the variety of riders, riding style and terrain) may actually fall between the two.

[icenutter]

I know this is WW, but lighter isn't always better. My 140mm travel 26er is so much more fun to ride when it's steep and rough than the hardtails. Granted on easy paths and roads its a pig haha.

What bike are you rocking? I'm also on a 140 mm 26", in my case an Ibis Mojo SL.

I've got a 2007 or 2008 Lapierre Zesty. It's a great bike; light enough to do XC, but plenty travel and strength for technical riding. I don't feel the need to replace it with a 27.5" or 29" equivalent. I do have a 29" hardtail which is better for XC though.

I've always wanted a Ibis Mojo, particularly after watching this video
https://player.vimeo.com/video/14622333

[jonasd]

Based on the 'evidence' (yes it's not conclusive) of the relative performance of 27" diameter wheels (called 27.5) versus the 28.5" (called 29 - both nominal based on a 2" tyre), I would say it's unlikely a larger wheel will be faster, in fact the optimum (if such a thing can be said to exist given the variety of riders, riding style and terrain) may actually fall between the two.

The only issue I see here is to really say for sure someone would need to build a 30-31" wheel/tire combo and then compare it to other size bikes, otherwise simply linearly extrapolating data from smaller wheel sizes doesn't really prove things. Now, I'm not saying I want this, heck, I'm still running a 26" FS. I'm just saying I think one (or more) brands will try this in the future. It would make most sense initially on L/XL frame sizes. But as materials get stronger and lighter, the case for larger wheels makes more sense. I'm glad that when I upgrade my 2008 26" FS bike to a 27.5 or 29er bike, with some carbon hoops I can have the larger wheels without a weight penalty (except for tires).

[mattr]

There are already 36ers floating about.........

[jonasd]

There are already 36ers floating about.........

But they aren't really mountain bikes (unless you are really into rigid MTB riding). Or maybe I've missed some and there are HT or FS 36ers out there? I think 36er is a bit drastic for people under 6ft, keeping it as a niche product, but a 32er full-suspension or HT... that could go mainstream in the future...

[mattr]

Oh, i know. Nothing more than a gimmick or something fun to play on.

Still, you can get the parts now!

[TheRookie]

A mate has a home built 36er and I've ridden it.

Limitation right now is rims and tyre availability is limited to fairly heavy, he used stretched out 29er tubes as the 36er tubes were 500g (yes heavier than a 26" nobby nic tyre!).

His was sized for a 5'5" women to ride (using an inline seatpost and shorter stem).

It rode OK, inertia was obviously a big issue but once up to speed on local XC/XC+ trails it was very good, hills were OK but forget going 1x (expect perhaps using Eagle), don't ride behind one though as the rooster tail of muck off the rear tyre was off the scale!

[CGT]

I know this is WW, but lighter isn't always better. My 140mm travel 26er is so much more fun to ride when it's steep and rough than the hardtails. Granted on easy paths and roads its a pig haha.

What bike are you rocking? I'm also on a 140 mm 26", in my case an Ibis Mojo SL.

I've got a 2007 or 2008 Lapierre Zesty. It's a great bike; light enough to do XC, but plenty travel and strength for technical riding. I don't feel the need to replace it with a 27.5" or 29" equivalent. I do have a 29" hardtail which is better for XC though.

I've always wanted a Ibis Mojo, particularly after watching this video
https://player.vimeo.com/video/14622333

Yeah, Lopes was killing it on the Mojo/Mojo SL. Insane actually, considering the geometry of the frame when compared to what is considered normal for a trail bike nowadays.

[Lelandjt]

This thread assumes that light XC parts are no longer available. The reality is that you can still build or buy a very light bike that is suited to climbing smooth trails. The change is that this is no longer the norm and the "average" bike is now a heavier and more capable machine that better matches the needs of most riders. It used to be that everyone was on XC bikes even though most people cared less about efficient riding on smooth trails and rather fun on technical trails and that sucked. Now we have options. I have a 17lb hardtail, 23lb 130mm, 27lb 150mm, and 28lb 160mm (all 27.5 wheels). I grab the bike I want to ride that day. Also, I haven't found a singletrack that is faster on the hardtail than the 130mm FS but I'm gonna build a 20ish lb 100mm 29" FS to try to bridge that gap.

[Lelandjt]

I know this is WW, but lighter isn't always better. My 140mm travel 26er is so much more fun to ride when it's steep and rough than the hardtails. Granted on easy paths and roads its a pig haha.

What bike are you rocking? I'm also on a 140 mm 26", in my case an Ibis Mojo SL.

I've got a 2007 or 2008 Lapierre Zesty. It's a great bike; light enough to do XC, but plenty travel and strength for technical riding. I don't feel the need to replace it with a 27.5" or 29" equivalent. I do have a 29" hardtail which is better for XC though.

I've always wanted a Ibis Mojo, particularly after watching this video
https://player.vimeo.com/video/14622333

We should have talked. I just sold my mint Mojo SL frame for $350.

[icenutter]

We should have talked. I just sold my mint Mojo SL frame for $350.

Nooooooooooooooo

[TheRookie]

XC bikes getting bullier isn't new, remember RS bringing in the World Cup Reba in 2006, 200g heavier than the then 28mm stanchion SID, but stiffer and with more travel and a better damper.

[poynt]

As a shortarse. 5'3 and lightweight 53kg is there a real advantage for me to switch to a bigger system from my very light 26" HT

[Lelandjt]

^I would strongly advise you NOT to get 29" wheels but 27.5 will roll a little faster over rough ground without giving you fit problems or too much added weight. Small difference but a benefit for sure.

[poynt]

^I would strongly advise you NOT to get 29" wheels but 27.5 will roll a little faster over rough ground without giving you fit problems or too much added weight. Small difference but a benefit for sure.

At least going to 27.5" would be a minor cost upgrade, ie: rims and a wheel rebuild and still keep and use my old WW stuff.