To drive a motorhome over 7,500 kg should require a category D License. At the moment to drive a Motorhome over 7,500 kg you need a C category on your driving license.
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The max legal length is 12 metres. But if you hold a D license (coach pvc) you are not allowed. I find that very unfair as the average Coach is 12.5 mts and can be more than 14,000 kg without passengers (with 52 adult passengers the total weight would be approximately 18,000 kg on average).
Coaches also have a higher speed restriction on motorways at 100kmh (62mph) compared to HGV class 2 at 96kmh (60mph). This is unfair and needs to be changed.