I see on the web that some buses had twin front axles in the past.
en.wikipedia.org/wiki/Bedford_VAL
What was the reason that, this design did not continue?
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...What was the reason that...
Didn't these have a front mounted engine and gearbox?
Perhaps the two axles were to carry the weight concentrated at the front of the coach, although I'd have thought a single axle would have been sufficient.
I worked on a similar style of coach which had a mid-mounted engine and only one front axle.
A post on here some time ago said the twin steering axle coaches were dreadful to drive, but I can't remember if the poster said why.
Last edited by: Iffy on Wed 16 Mar 11 at 12:08
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I would guess it was to do with maximum axle load.
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Don't know if that was part of the reason for the design but the VAL also had smaller wheels than other coaches of the time, resulting in a lower floor. This enabled it to be used as a transporter in later life in many cases, including of course Mr Caine and his Mini Coopers.
I believe it also makes them more maneuverable, the driver of the last one I rode in, in Liverpool reckoned it was easier round corners in suburban streets than many modern coaches.
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Not sure but I think the engine was still in the middle on them iffy, the Stock Car boys used a fair number of them to cart the F1s around...
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The engine on the VAL was definitely at the front, a big lump right beside the driver
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And to prove it:
www.flickr.com/photos/22455491@N02/4799590937/
Time playing with my mind again... I'm sure i saw the driver underneath the side on his coach... Must have been a different make!
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put
'twin steer coaches'
into youatuber
or click
www.youtube.com/watch?v=4gUWlx-LwHY
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They were awfull to drive. very heavy steering, used to have to stand up to turn the wheel when parking. I also belive the twin axles were to support the weight of the power train. The last time it came up for discussion was the italian job! Great film
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I thought at least some of them had power steering, certainly in the one in Liverpool on the Beatles tour the driver didn't appear to be struggling
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They had what was called semi power steering !
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I can just about remember these, my primary school closed during 1989 as they were fitting a new roof so we had to be transported to another building 1.5 miles away. The coaches used were old bangers and they had a couple of late 60's VALs.
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Istr the reason for three axles on a coach was (at the time) vehicle length ie: you could have a longer bus with three axles. Two axles at the rear can cause a problem with tyre wear, so Bedford put two at the front.
The rules then changed, allowing a longer bus on two axles, so the design fell out of fashion.
Modern three axle coaches (think National Express) get round the tyre wear issue by having a steering rear axle, which is only active at low speed. This may have contributed to a motorway coach crash some years ago when the rear axle became 'unlocked' at speed.
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Looking at the British Bus Conversion website, they say this about the Bedford VAL:
"But why did Bedford go for the twin steer arrangement? One key factor was those small 16in diameter wheels. 20in had been virtually universal on both buses & coaches for many years, but there had been, for 15 years or more, a trend in the field of private cars towards the use of relatively smaller wheels. Such refinement led to reduced weight - not only in the wheel itself, but in its associated suspension & steering gear - & to more available space. On a bus or coach chassis the use of two front axles make smaller wheels practical, & allows the floor height to be lowered eliminating wheel arch intrusion. The arrangement brought with it improved ride quality, & moreover, Bedford was able to use existing parts from their TK truck range, obviating the need to develop a new front axle."
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Maybe the designer was influenced by Lady Penelope's pink Rolls Royce?
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Bus with twin front axles - Iffy
