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New technology in buses
#1
Following regular references to bus engines, Euro ratings, hybrid technology and a mention of it by G-Cptn, thought it worthwhile setting up a dedicated thread.

On the forum, there are regular comments about buses being underpowered and unsuitable for the routes allocated, whether it is specific to the E400's, B7's cascaded from London, newer B5's, gas buses and the oft forgotten Designlines.

The big three operators have all embraced new technology in their fleet, purchasing a hotch potch of vehicles - using different pots of taxpayer money, to supplement their outlay.

What are peoples thoughts on these vehicles? Are they going to last the length of time, the initial outlay would indicate they should?
Who will purchase the vehicles at the end of their frontline life in the North East?
'Illegitimis non carborundum'
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#2
My initial interest was the now-defunct DesignLine gas-turbine-engined vehicles used by Stagecoach on the Quaylink service.

Apparently they cost £5000 per week of operation (and were scrapped after 6 years service).

I suspect the current hybrids will be more reliable and last longer, but what about the whole life cost and the running costs?

Several operators seem to have tried them and rejected them as not being as cheap to run as they hoped.
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#3
Basically, we need a double deck vehicle manufacturer that will come up with a vehicle and chassis combination that will provide for routes where a heavyweight single deck such as the B8RLE hasn't got the capacity but the investment of a coach couldn't be justified due to financial and operational reasons (cascading vehicles). Ideally, we need a low floor double deck vehicle that:

- Meets Euro legislation
- Has at least a 9 litre engine with 270bhp or more
- Has a gear box with tall gearing ratios for constant high speeds
- Is double deck and low floor
- Is priced at around 200k mark or less
- Will last 7 years on a demanding route (X15 or X18)
- Will last a further 7 to 8 years on slightly less demanding routes (X14 or X20) whilst acting as a backup for previous demanding route (X18) with the very final 2 years before 15 year life span coming to an end backing up on routes such as 35, X14, X20, X21 and X22
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#4
(23/03/2014, 00:12)Davey Bowyer Wrote: Basically, we need a double deck vehicle manufacturer that will come up with a vehicle and chassis combination that will provide for routes where a heavyweight single deck such as the B8RLE hasn't got the capacity but the investment of a coach couldn't be justified due to financial and operational reasons (cascading vehicles). Ideally, we need a low floor double deck vehicle that:

- Meets Euro legislation
- Has at least a 9 litre engine with 270bhp or more
- Has a gear box with tall gearing ratios for constant high speeds
- Is double deck and low floor
- Is priced at around 200k mark or less
- Will last 7 years on a demanding route (X15 or X18)
- Will last a further 7 to 8 years on slightly less demanding routes (X14 or X20) whilst acting as a backup for previous demanding route (X18) with the very final 2 years before 15 year life span coming to an end backing up on routes such as 35, X14, X20, X21 and X22

Can I ask the fascination about 9 litre engines? You can produce the same horsepower (and more) on smaller engine capacities than than.
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#5
(23/03/2014, 00:39)aureolin Wrote: Can I ask the fascination about 9 litre engines? You can produce the same horsepower (and more) on smaller engine capacities than than.

Indeed, reading articles will show that the upcoming Euro6 B5TL will produce 240bhp, which is about what most B9TLs produce (a small number of the Go North East examples have more powerful engines). Compare that to Scania, it ranks 10bhp above Stagecoach's preferred engine choice on the Scanias, the 230bhp (K230 or N230).
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#6
Horsepower is one thing - torque is the other.
Turbocharging increases the torque (though might reduce the spread).

I believe that alternative gearing is already available (from ZF-equipped vehicles).
Both by specifying one of three final drive ratios and/or by double-overdrive (6AP speed) transmission.
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#7
(23/03/2014, 00:42)Kuyoyo Wrote: Indeed, reading articles will show that the upcoming Euro6 B5TL will produce 240bhp, which is about what most B9TLs produce (a small number of the Go North East examples have more powerful engines). Compare that to Scania, it ranks 10bhp above Stagecoach's preferred engine choice on the Scanias, the 230bhp (K230 or N230).

I agree with there however, in comparison to a small engine, a big engine with the correct gearing will hodl the road and be alot smoother at constant high speed. The palatines did exactly that.
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#8
B9 datasheet (includes horsepower and torque figures and available transmission ratios - both final drive and transmission ratios):-
http://www.volvobuses.com/SiteCollection....09.12.pdf

I'm searching for comparative datasheets for other models.
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#9
A quick comparison of current Euro6 engines from Volvo http://www.volvobuses.com/bus/na/en-us/_...uage=en-gb

Looking ay the discussion re engine size and bhp - my last two cars have been 1.6 and 1.9 respectively. One a Ford engine, the other a VW.
Both put out a similar bhp, emissions, fuel economy etc and both cars are of a similar size/design.

When humping them up and down the motorway, usually at a similar sort of speed, the 1.6 version needs to work harder than the 1.9 by virtue of its design and size.

If you compare the B7 to a B9, are you not going to have the same issues?
If two cars are performing different and there is just under a 1/3 of a litre between them, what sort of difference will there be between two buses which have a 2litre variance?
'Illegitimis non carborundum'
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#10
Many, many years ago, Jaguar ran a 3.4 litre in convoy with a 2.4 litre (obviously dictated by the performance of the 2.4 litre).
The 3.4 litre returned better fuel consumption (no doubt due to the longer gearing than the 2.4 litre and lower overall revs).

This could mean that, for the same performance, a larger capacity (and suitably geared) B9 could better a B7 for consumption.

Of course this would depend on the relative degree of sophistication of the emission control.

Lifetime of the smaller capacity engine might be lower than the larger, less-stressed engine (or, expressed differently, the larger capacity engine might be less troublesome in later life and therefore last longer).

Just saying. Actual experience would depend on route performance duty.

A good biggun will beat a good littlun.
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