COMPREHENSIVE INNER TUBE ROLLING RESISTANCE DATA

UPDATED

(CONTINENTAL / MICHELIN / SCHWALBE / CHALLENGE / HUTCHINSON / TUBOLITO / VITTORIA)

 

INTRODUCTION

 

Cyclists have long known about the importance of rolling resistance in selecting tyres for racing, group rides or even general training. A high rolling resistance will require more power to travel at the same speed, whilst low rolling resistance requires less power.


We performed a test on a large number of different inner tubes to see how they affected rolling resistance. Construction varied from plastic (Tubolito), latex (Challenge, Vittoria, Michelin) as well as butyl (Continental, Schwalbe, Michelin, Hutchinson)

We used a Continental GP 5000 clincher tyre in 25mm to perform the test, and you can see how the GP 5000 clincher performs here: GP 5000 DATA

The goal of this test was to evaluate the rolling resistance performance of different types of inner tubes.


THE TUBES

Having previously tested a variety of tyres, it's also important to make sure your inner tube choice is also correct as this also affects your rolling resistance. In this test we kept with one model of clincher tyre - the Continental GP 5000 in 25mm.


All the inner tubes and tyres were mounted on a shallow section aluminium rim, with an external rim width of 24.7mm and an internal rim width of 19.6mm, and inflated to 90psi.
 

Vittoria Latex

Weight 72g

Challenge latex

Weight 74g

Michelin Aircomp latex
Weight 81g

Continental Race Supersonic

Weight 55g

Continental Race light

Weight 78g 

Continental Race

Weight 104g

Michelin Ultralight
Weight 76g

Schwalbe Extralight

Weight 80g

Hutchinson Airlight
Weight 80g

Tubolito

Weight 40g

 

WEIGHT

The Tubolito inner tube was by far the lightest on test, weighing 15g less than a Continental Race Supersonic inner tube, and 64g less than the heaviest tube (a Continental Race. 64g saved per wheel over a Continental Race tube gives a wheelset saving of 128g, which irrespective of rolling resistance will be a little faster - for a flat course 128g will be a minimal to no real saving, but if travelling uphill at 16kph on a 10% gradient, a 128g weight saving would equate to 0.6w saved, or a speed increase of 0.02kph. However - rolling resistance has much more of an impact than weight, read on to see the difference in rolling resistance.


 

ROLLING RESISTANCE RESULTS

In order to test rolling resistance, we used the same tyres and swapped between them as a rider rode a bike on rollers, measuring power output and speed, as well as atmospheric conditions and bike/rider weight. This allows us to calculate what is known as the Coefficient of Rolling Resistance (or "Crr"), which can be used to model the power output required to travel on a normal road. A lower Crr is better - in that it requires less power to travel at the same speed.


The updated results of the roller testing are shown below, as well as a chart showing weight differences:

 

The Vittoria latex tube and the Challenge latex tubes were the fastest, saving over 7w for a pair of wheels compared with a standard butyl Continental Race inner tube. 


All latex tubes were faster than other tubes (Butyl & Tubolito).


An extremely light Continental Race Supersonic was heavier than a Tubolito tube, but faster overall as the rolling resistance was less. The difference between a Continental Supersonic / Continental Race was 4w for a pair of wheels.


At 45kph, the difference between the fastest and slowest inner tubes would equate to around 12sec over 16km/10 miles.

 

SUMMARY

In this updated test we found that there was a large difference in rolling resistance between different models of inner tubes, with standard butyl tubes being the heaviest and the slowest on test.

Latex inner tubes outweigh any small penalty from ultra light tubes like Tubolitos or a Continental Race Supersonic as the rolling resistance with a latex tube is so much lower (better). One small drawback with latex tubes is that they lose air overnight and require pumping up before a ride - so if you want to have an inner tube that's a little bit faster than a standard butyl tube and doesn't require daily inflation, Tubolito or Continental Race Supersonic would be two alternatives.