Aidan Bishop has been riding and racing all types of mountain bikes ever since they were invented. He’s ridden all over the world and on all sorts of bikes – from hardtail cross-country race bikes to full-on downhill rigs – he certainly knows his bikes. Recently he went out to try and conduct his own test to see which was faster around his local singletrack loop.

Cannondale 26″ vs 29″ wheel XC speedtest. from aidan bishop on Vimeo.

Conclusive results? Does the test need to be more scientific? We asked Aidan to tell us a bit more about his riding history and the findings from his test:

“Hi, I’m Aidan Bishop.  I would class myself as a cycling enthusiast.

I’ve been riding and racing mountain bikes since 1989, where did the time go…? I started out XC racing then, then when DH (downhill) racing emerged, I concentrated on the gravity side of things, racing in the Pro category for many years. Recently I have been Masters national series DH champion, but have now turned my attention to riding all disciplines of cycling, concentrating on racing gravity enduros and mass start DH events like the Megavalanche. Cannondale, Mavic, Giro, GoPro, Crank Brothers, RRP, Maxxis and 661 support me.

I started out XC racing then, then when DH (downhill) racing emerged, I concentrated on the gravity side of things, racing in the Pro category for many years.

Next year will be more of the same: early season XC racing for fitness and competition; then mixing up as many gravity enduro events worldwide as I can make it to, especially with the new World Enduro Series now launched.  I’m sticking with the Cannondale Jekyll carbon, Mavic wheels and apparel and my other sponsors, allowing me to race with the parts I want to ride.

During early season I race a fair bit of XC, this year I found myself battling with riders on 29” wheeled bikes and I kept thinking ‘am I working harder than him to keep pace?’. With my local XC races kicking off in the new year I’ve been thinking more and more about whether to make the change from 26” to 29” wheels. I was kindly loaned a lovely Cannondale F29 carbon 1 to try out to see what there are like. Then I came up with the idea to try to directly compare the wheel sizes and see what time difference there is between the two in a simulated XC race lap.

With my local XC races kicking off in the new year I’ve been thinking more and more about whether to make the change from 26” to 29” wheels.

My current XC race bike is a Cannondale Scalpel carbon with 26” wheels.  In an effort to make the bikes as similar as possible (the Scalpel being short travel full sus) I set the rear shock to be locked out; so as to be as close to a hardtail as I could make it.  I then fitted Mavic Crossmax SLR wheels to the Flash 29er (I already run 26” Mavic’s on the Scalpel), these were both fitted with the same Maxxis tyres (Ignitor front, Ikon rear). Both sets of tyres were inflated to 35psi so I had matching pressures, tyres and wheels. So I knew handling, grip and traction would be an identical test at least.  The Flash 29er came with flat bars so I swapped them out for a set of Crank Brothers carbon riser bars as I haven’t ridden flat bars for decades!

Both sets of tyres were inflated to 35psi so I had matching pressures, tyres and wheels. So I knew handling, grip and traction would be an identical test at least.

So with the bikes as similar as I could make them I mapped out an XC lap of my local woods in Crowthorne (I’ve raced Gorrick MBC XC races there off and on for the past 20years). Afterwards the Strava App mapped it out to be 3.6 miles long, consisting of fire roads, singletrack and ups and downs in equal measure.  As a little warm up, so I wasn’t racing the first lap cold, I filmed little clips here and there on both bikes and this was the very first time trying the 29er. I then set out on the first timed lap on my 26” wheeled Scalpel, stopping the clock at 19mins 15secs.  Then it was the turn of the Flash F29 after a 5 min break to recover, the same exact lap done with the time 18mins 27secs. That’s 48 seconds quicker!

As a little warm up, so I wasn’t racing the first lap cold, I filmed little clips here and there on both bikes and this was the very first time trying the 29er.

I am very much a ‘get on and ride’ kind of rider, I can’t say I could notice the difference of 1 degree in head angles or 10mm lower bottom bracket, etc.  So my main comparisons are the more blatant differences I could feel.  I liked the higher cockpit the 29er gave me, I felt more confident going off steep drops or chutes and it felt I was sitting ‘in’ the bike more than ‘on’ it.  The tyres were the same pressure but almost felt ‘flat’ on 26” wheels, I guess this comes down to the volume difference of the tyres maybe?  26” wheels are quicker to react and throw around when you push hard into and around corners over the 29er, that’s not to say the 29” were slow however.

The tyres were the same pressure but almost felt ‘flat’ on 26” wheels, I guess this comes down to the volume difference of the tyres maybe?

A big difference I noticed was on the first quick climb.  You carry good speed up most of it out of the saddle but the last 5 metres or so slow up considerably due to gradient and the 26” wheels struggled for grip on the gravelly surface.  The 29” wheels noticeably carried better speed over the top of the climb, not fighting for traction as much and therefore not working your heart rate as much enabling you to recover quicker and keep speed rolling.

So those were the main differences I noticed, and 48secs over one lap is a considerable margin.  The only regret was that I forgot to fit my heart-rate monitor strap so I couldn’t monitor my average heart-rate over the two laps. A power meter would be the other item that would make the test even closer to monitor as you could see the effort you were putting in and match it for both laps, but as I don’t have one that was a no go.

48secs over one lap is a considerable margin.

I’m now going to sell my 26” bike and get the F29 for racing XC on as if I want to compete I will be at a disadvantage on 26” wheels where most are on 29”. I hope this video might help others who were thinking along the same lines as me, it was certainly informative for me.  I am now seriously considering bigger wheels for enduro racing.”

What do you think about Aidan’s test? Could/should it have been more scientific or is this just the sort of evidence you were looking for? Let us know in the comments below.