Just looking at my stats on Veloviewer and I noticed that I have over 50 hours of data for five different mountain bikes. That should be enough to start to smooth out variations in day to day fitness, weather etc and start to get a feel for the relative speed of each bike. So, here are the average speed results in order.

Solaris (29er hardtail) ———————- 7.1 mph
Solaris Chubby (same bike with plus tyres)—- 6.8 mph
Smuggler (full-suss 29er) ——————– 6.6 mph
Surly ICT (5″ rigid fatbike)—————— 6.5 mph
Five (26″ full-suss) ————————- 6.3 mph

For comparison the average speed on the road bike is 15.3 mph (what can I say, it’s hilly up here).

Since they are average speeds they will be mainly affected by climbing speed. Make of them what you will, but I was surprised by how little variation there was between the bikes. I’d expected the fatbike to be significantly slower, to be honest.

Did you ride them all on the same trails in the same conditions or would each be favoured for different rides and/or conditions?

Do you do the same type of rides on all the different bikes ? I tend to pick whatever one I think would be most suited to a particular ride. Hence my average speeds vary greatly from bike to bike.

As well as the above variations, are your builds identical, riding positions identical?

I tend to be motivated to pedal harder on better climbing bikes, so vastly exaggerate the difference between different bikes (conversely on the big bike particularly I often finish descents more out of breath than I finish the climbs).

Well, I’m not planning on publishing this in Nature or anything, but there are no obvious biases. The bikes all tended to be ridden on the same trails (North-East Scotland XC bimbling) and the weather conditions will tend to average out. I don’t really favour a particular bike for a particular type of trail. In fact I quite enjoy riding things on inappropriate bikes, just for a laugh.

That’s probably why the average speeds are so close to each other. If one bike tended to get used on nicer days or smoother routes or something, the differences would probably be bigger.

As for effort, I basically like to ride up a hill as fast as I can whatever bike I’m on. It might not be that fast, but it’s usually as fast as I can manage.

There does seem to be a nice trend with tyre size: going from “normal” to plus drops the average by 0.3mph and then going to full-fat drops it by another 0.3mph. However, going from a hardtail to a full suss seems to incur a larger penalty than a fatter tyre and a 29er comes out a bit faster on average than a 26″ bike.

But, of course, this is all just average speed, which will be dominated by climbing speed. If all you care about is the time taken on the descents then this is irrelevant!

I have a full sus 26″ bike, a carbon 29er hardtail and a fatbike.

After riding them all on my local south downs routes, I’ve been very surprised at how the fat bike has compared. Average speed is a little lower but nowhere near as much as I thought it would be and it’s the fastest bike downhill.

VeloViewer fun…

Focus Cayo (carbon roadie) – 24.8
Cube GTC Agree (carbon roadie) – 24.6
VN Amazon (Ti tourer) – 19.8
Salsa El Mariachi (Steel 29er) – 14.5
Burls Ti 29er – 14.3
Pact Wildcat (Ti B+ hardtail) – 14.0
Onion (Ti 26er hardtail) – 13.8
9ZERO7 (Alu 4″ Fatbike) – 12.6
SC Blur Carbon (XC FS ) – 12.0

(all in kph btw)

Other than the Blur, it seems like a reasonable progression from skinny to fat and I’m not sure how to explain that anomaly.

That stat wouldn’t be useul for me 🙂 Average speed on my Patriot is likely to be far lower, because I winch it up to the top of big things, stop to catch my breath, check out some lines, and then launch down it. The rigid 29er gets used for long mixed road/off-road trails, and the XC bike (if I were still riding it) got used exclusively for XC races!

The Strava times should be moving times, not total times, so that would remove any hanging around waiting for slower riders 😉 It does seem like a reasonable analysis though. My Blur doesn’t get used at all these days for long XC type routes through the countryside.

I’ve got overall times to do my local loop on strava. My fastest time is on my farley and the other bikes are a 29 and 650b plus hardtail, 650b full suss, a 29er and a 650b hardtail. The margin was nearly two minutes.

Damn, I should have quoted the speeds in kph 🙂

Yes, all moving times. Interesting to see another example of a fatbike not being slowest, 29ers being faster than smaller wheels and full-suss incurring quite a penalty.

On my local mountain road circuit:

4.8″ fat bike: 9.1mph
Road bike: 10mph

Can you provide a break down by geometry, tyre pressure and colour?

And stem length

Damn, I should have quoted the speeds in kph

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