That tyre selection can have an effect on the amount of fuel used by a tractor has, one suspects, been a notion many would concur with. But, until now at least, there has been little if any solid evidence to substantiate such claims.

So a series of trials, organised by Michelin’s contractor panel in association with Claas, to provide proof that fuel consumption can be reduced if greater attention is given to tyre selection and operating pressures, is perhaps one to be welcomed.

Held in a field near Claas UK’s headquarters at Saxham, Suffolk, the trials also called on the expertise of Scarlett Research to gather test data and to provide the final analysis.

The trials comprised two basic components: a tractor coupled to a seven-furrow plough working with different tyres and two identically loaded trailers shod on different tyre types.

For the ploughing trial, a Claas Axion 820 was equipped with electronic equipment that produced five key pieces of data – the amount of pull produced by the tractor, the operating speed, the wheel slip percentage, the power used and the volume of fuel used.

This first trial saw a comparison between the Axion fitted with Michelin’s Agribib tyres, which the company describes as its ‘standard’ offering, and then with it using Ultraflex Xeobib tyres which provide a larger footprint.

Working in dry, light soil conditions – which, it was conceded, were not going to provide the best results in terms of performance differences – the tractor set forth with the Lemken plough. As it did so, Scarlett Research’s electronics whirred into action to record and display each and every drop of fuel consumed.

The full results of the test can be seen below, but the most interesting one is that, on this occasion, fuel use for the Xeobib tyres was 1.15-litres/ha less than when the Agribib tyres were fitted – 11.61-litres/ha rather than 12.76 litres, which equates to a 9% reduction.

Other notable differences included a reduction in wheel slip by nearly 5% and an increase in forward speed.

All of which would appear to make a strong case for Xeobib tyres which operate at less than half the pressure of Agribibs. This feature, combined with the larger footprint, also reduces compaction, according to Michelin.

There was similar news in the trailer trial where one of the trailers was fitted with the ‘conventional’ 385/65R22.5 Super Single tyre operating at its recommended 90psi and the other with 560/60R22.5 flotation tyres running at 32psi.

Pulled by a Claas Arion 640 running on Multibib tyres, the results were quite significant with fuel savings calculated at a massive 45.8% when the flotation tyres were in action.

The draught loading recorded to pull these similarly loaded trailers on flotation tyres was half that required when on they were on conventional tyres (The gross weight of tractor, trailer and load was just over 24t).

While the flotation tyres clearly cost significantly more – about £1500, says Michelin – the company points out that the saving in fuel and the reduction in soil compaction and all that entails – make them a better deal overall.