UK speed limits for coaches on a Motorway

[shanklyone]

Hi,
I always understood that Coaches (ie your typical national express type coaches) were allowed to travel 70mph on a motorway but having looked in the highway code it distinguishes between buses of less than or more than 12m length. So anything over 12m is 60mph and under 12m is 70mph.
This would make your typical national express type coach limited to 60mph (because I figure these are more than 12m in length).
Am I right?
If I'm wrong then if anybody has the link towards the official legislation then that would be very useful.
Thanks a lot for your help

[AndyB]

Typical rigid two axle bus or coach is 11-12m. I think that only articulated or three axle buses (including Plaxton’s low floor 14m fully accessible coach) get into that realm.

In practice, modern buses and coaches have limiters set at 100km/h (62mph) in the same way as lorry limiters are set at 90km/h (56mph) even though a lorry may theoretically travel up to 60mph on a motorway.

[AndyB]

PS RTRA 1984 Schedule 6

[Alf27]

"a lorry may theoretically travel up to 60mph on a motorway."

Quite correct but I was told that if you did travel above the "limited speed" that you will not be prosecuted for speeding, but for not complying with Construction & use regulations, this includes when gaining speed on downhill sections, most modern digital tachographs will flash a warning if this is done for more than a few seconds.

[AndyB]

Makes sense - the limiter can prevent you using the engine to accelerate above the relevant speed, but it can't combat gravity.

[fras]

Makes sense - the limiter can prevent you using the engine to accelerate above the relevant speed, but it can't combat gravity.

Actually, I think it is more sophisticated and puts the brakes on if necessary.

[avtur]

Makes sense - the limiter can prevent you using the engine to accelerate above the relevant speed, but it can't combat gravity.

Actually, I think it is more sophisticated and puts the brakes on if necessary.

The 'automated' system that would limit speed when overrunning downhill would be cruise control, the limiter is just that, it limits the engines ability to produce power above the preset speed. Engine braking in many instances would simply not be sufficient to restrain the speed of the vehicle when travelling downhill, the only way speed can be controlled is by use of brakes, the more sophisticated ABS systems do interact with braking systems.

[Ruperts Trooper]

Limiters can work in two ways - in their simplest version they simply stop injecting fuel once the set speed is reached, these can overspeed on downhill sections - a more sophisticated version does the same but will apply the brakes through the ABS to prevent the set speed being exceeded.

Cruise controls can equally have two different versions - my VW Touareg uses the simplest version so can overspeed downhill.

[avtur]

Makes sense - the limiter can prevent you using the engine to accelerate above the relevant speed, but it can't combat gravity.

Actually, I think it is more sophisticated and puts the brakes on if necessary.

The 'automated' system that would limit speed when overrunning downhill would be cruise control, the limiter is just that, it limits the engines ability to produce power above the preset speed. Engine braking in many instances would simply not be sufficient to restrain the speed of the vehicle when travelling downhill, the only way speed can be controlled is by use of brakes, the more sophisticated ABS systems do interact with braking systems.

Ooops, need to correct a typo I made in the previous comment, I said 'ABS' I meant 'Cruise control' (been a long and busy day!) The recent HGV 's I've driven all had cruise control which would apply brakes to avoid downhill over speed "if the cruise control was in use", if the cruise wasn't in use then it's down to the driver to apply the brakes to avoid a downhill overspeed. My 12 year old Benz car has brakes operated by cruise control, its not a new idea.

[AutomaticBeloved]

Most coaches these days are over 12m. Megabus use 15m - I think National Express are standardising on 14m for new orders. Also recent rules changes mean you can go to 13m on 2 axles - which I imagine would be a sod to manoeuvre without the steering tag axle

[KeithW]

Limiters can work in two ways - in their simplest version they simply stop injecting fuel once the set speed is reached, these can overspeed on downhill sections - a more sophisticated version does the same but will apply the brakes through the ABS to prevent the set speed being exceeded.

Cruise controls can equally have two different versions - my VW Touareg uses the simplest version so can overspeed downhill.

Most new vehicles have the option of adaptive cruise control which not only controls speed downhill but maintains a variable distance from the vehicle in front. If I opt to use the limiter, which I usually do on S2 roads, then those functions are down to me.

[Ruperts Trooper]

Limiters can work in two ways - in their simplest version they simply stop injecting fuel once the set speed is reached, these can overspeed on downhill sections - a more sophisticated version does the same but will apply the brakes through the ABS to prevent the set speed being exceeded.

Cruise controls can equally have two different versions - my VW Touareg uses the simplest version so can overspeed downhill.

Most new vehicles have the option of adaptive cruise control which not only controls speed downhill but maintains a variable distance from the vehicle in front. If I opt to use the limiter, which I usually do on S2 roads, then those functions are down to me.

My cruise control is basic - no adaptive, no auto braking - but I find it adequate for my needs - adaptive cruise was an option when I bought the car but I didn't think it worth it.

[Fenlander]

My cruise is fixed too, adaptive was a cost option but buried in a pack I didn't want on price grounds. I use cruise a lot, almost as a form of sticky limiter for 30s & 40s as much as NSL. It's a doddle to fine tune it to traffic conditions plus there's always cancel & resume if traffic varies too much. It's much easier to keep the eyes outside than down on the speedo that way.

[Ruperts Trooper]

My cruise is fixed too, adaptive was a cost option but buried in a pack I didn't want on price grounds. I use cruise a lot, almost as a form of sticky limiter for 30s & 40s as much as NSL. It's a doddle to fine tune it to traffic conditions plus there's always cancel & resume if traffic varies too much. It's much easier to keep the eyes outside than down on the speedo that way.

Yes, I find it useful for all speed limits from 30 upwards - mine's not smooth when set to 20 so I don't use it there.

[Fenlander]

20 is the lowest I can set mine too but I never really come across any situations where that would be useful, much below 30 and traffic tends to become turbulent start & stop stuff anyway. The other speed control aid I used to use was tickover in 2nd in my previous diesel manual, I found it (approx 7mph) was the perfect speed to smooth out the start & stop surges in the queue on the road that leads to my house at 5PM. Now I've gone automatic creep is too slow to do that.

[rhyds]

My Focus' cruise control (retrofitted by me) won't activate under 30mph, however its great for 50mph average speed sections.

[Piatkow]

With only basic cruise control I prefer to use the limiter in heavy traffic. It doesn't cancel if I have to change down and seems to give better fuel consumption as I can adjust the pressure on my right foot.

[Ronnie]

My (Vauxhall) cruise control will hold the car at 16mph but no lower than that. After we leave the EU will coaches and lorries still need to have speed limiters or can these be removed?

[A9NWIL]

My (Vauxhall) cruise control will hold the car at 16mph but no lower than that. After we leave the EU will coaches and lorries still need to have speed limiters or can these be removed?

I imagine they have cut and paste the laws regarding motoring into UK law, they likely have no reason to change them. Unless of course a backwards government decides to change the both to 60mph instead of 90km/h and 100km/h.

[Ruperts Trooper]

My (Vauxhall) cruise control will hold the car at 16mph but no lower than that. After we leave the EU will coaches and lorries still need to have speed limiters or can these be removed?

My understanding is that all EU law has been enacted into UK law so nothing changes until we change it - I've not heard any support for removing truck/coach limiters.