On 6 Jul, 11:05, Adrian wrote:
Don't forget that the engine is basically just being used as a generator,
therefore can run at optimum revs for the specific output - there's no
requirement for any kind of useful rev range or torque curve.

True , and I suppose that will mitigate it somewhat. However
ultimately that engine will produce less power than a normal bus
engine so when relying on the engine alone its going to be slower
compared to the normal engine running at optimum gearing.

B2003

Boltar ) gurgled happily, sounding much like they
were saying :

Don't forget that the engine is basically just being used as a
generator, therefore can run at optimum revs for the specific output
- there's no requirement for any kind of useful rev range or torque
curve.

True , and I suppose that will mitigate it somewhat. However
ultimately that engine will produce less power than a normal bus
engine so when relying on the engine alone its going to be slower
compared to the normal engine running at optimum gearing.

shrug
How often do bus engines require full power? Not very.

Don't forget that one thing electric motors are very good at is producing
large amounts of torque from rest.

On 6 Jul, 11:16, Adrian wrote:
shrug
How often do bus engines require full power? Not very.

Agreed but when they do need it they really need it. The steep hills
around mill hill, highgate , hampstead and southgate spring to mind. A
hybrid bus with an exhausted battery going up one of those hills won't
be very popular with other motorists.

B2003

Boltar ) gurgled happily, sounding much like they
were saying :

shrug
How often do bus engines require full power? Not very.

Agreed but when they do need it they really need it. The steep hills
around mill hill, highgate , hampstead and southgate spring to mind. A
hybrid bus with an exhausted battery going up one of those hills won't
be very popular with other motorists.

Nor would a diesel bus with an empty fuel tank...

I really don't think it's going to be an issue.

On 6 Jul, 11:35, Adrian wrote:
Boltar ) gurgled happily, sounding much like they
were saying :

shrug
How often do bus engines require full power? Not very.
Agreed but when they do need it they really need it. The steep hills
around mill hill, highgate , hampstead and southgate spring to mind. A
hybrid bus with an exhausted battery going up one of those hills won't
be very popular with other motorists.

Nor would a diesel bus with an empty fuel tank...

I really don't think it's going to be an issue.

A buses diesel fuel probably lasts all day. If these hybrid buses are
anything like hybrid cars then the battery would run down after only a
few miles without topping up which means its quite possible the bus
could be relying on engine power alone on difficult routes such as I
mentioned if the engine doesn't have the surplus to charge the battery
as well as supplying the motors.

B2003

Boltar ) gurgled happily, sounding much like they
were saying :

shrug
How often do bus engines require full power? Not very.

Agreed but when they do need it they really need it. The steep hills
around mill hill, highgate , hampstead and southgate spring to mind. A
hybrid bus with an exhausted battery going up one of those hills won't
be very popular with other motorists.

Nor would a diesel bus with an empty fuel tank...

I really don't think it's going to be an issue.

A buses diesel fuel probably lasts all day.

And...?

If these hybrid buses are anything like hybrid cars then the battery
would run down after only a few miles without topping up which means its
quite possible the bus could be relying on engine power alone on
difficult routes such as I mentioned if the engine doesn't have the
surplus to charge the battery as well as supplying the motors.

But the engine'll be keeping the batteries brimmed as much as possible, so
it'll arrive at the bottom of the hill with full charge - which will be
perfectly adequate for the ascent. Don't forget that the only real
restriction on battery capacity in hybrid cars is the physical packaging
constraints - which just don't apply to a bus.

Boltar wrote:
On 6 Jul, 11:16, Adrian wrote:
shrug
How often do bus engines require full power? Not very.

Agreed but when they do need it they really need it. The steep hills
around mill hill, highgate , hampstead and southgate spring to mind.

Even if the buses were unsuitable for those areas, that's only about a dozen
routes. You wouldn't say that double deckers will never work in London
because of the Rotherhithe Tunnel.

On Fri, 6 Jul 2007 12:26:49 +0100, "John Rowland"
wrote:

Boltar wrote:
On 6 Jul, 11:16, Adrian wrote:
shrug
How often do bus engines require full power? Not very.

Agreed but when they do need it they really need it. The steep hills
around mill hill, highgate , hampstead and southgate spring to mind.

Even if the buses were unsuitable for those areas, that's only about a dozen
routes. You wouldn't say that double deckers will never work in London
because of the Rotherhithe Tunnel.


True, as double deckers have been used in it, haven't they?

Ken Wheatley wrote:
On Fri, 6 Jul 2007 12:26:49 +0100, "John Rowland"
wrote:

Boltar wrote:
On 6 Jul, 11:16, Adrian wrote:
shrug
How often do bus engines require full power? Not very.

Agreed but when they do need it they really need it. The steep
hills around mill hill, highgate , hampstead and southgate spring
to mind.

Even if the buses were unsuitable for those areas, that's only about
a dozen routes. You wouldn't say that double deckers will never work
in London because of the Rotherhithe Tunnel.


True, as double deckers have been used in it, haven't they?

I doubt it... a normal single decker won't fit.

In message , John Rowland
writes

Rotherhithe tunnel

I doubt it... a normal single decker won't fit.

The double-deck route 82 used to run through the tunnel until the 1960s.
Here's one just emerging from the northern exit:

http://www.busesatwork.co.uk/051-100...82_RTL1613.jpg

I have a feeling that the roadway through the tunnel was lower in those
days (as it was in the Blackwall tunnel), giving better height clearance
at the expense of (even) narrower width. Apparently buses on route 82
were equipped with specially reinforced tyres to mitigate the constant
rubbing on the kerb while going through the tunnel.
--
Paul Terry