Living out here in the countryside most of my journeys of any distance seem to end up with a train of traffic following me and me looking for lay bys to pull into to let them all pass.
My bus seems to want to travel at about 36 to 38 is this about what everybody else is doing or should I be able to get more out of her.
We avoid motorways purely because we have visions of somebody rear ending us.I don't want to set the world on fire but should we be able to get along faster.
2478 has the Cummins engine and original gearbox and diff as far as we know.


Graham

My bus number (if any): RML 2478

Hi Graham,

I think there’s no getting away from the fact that it is a 1950’s Double Deck stage carriage bus, designed for pottering around town. 30mph would have been it’s intended maximum and normally in town you wouldn’t be anywhere near that. I know there were Greenline Coaches and the BEA buses but they were special and adapted to higher speed operation. I can remember driving back to Upton Park at 01.00 in the morning down the Commercial Road and pushing 30 in a standard RML and it felt like bits were starting to fall off!

I know there’s been a lot of changes over the years with engines and running gear and some people are happy on the motorway at 60 but in all honesty if I was travelling cross country between 30 & 40 I’d think I’d was doing ok.

What Danny has said really sums up the situation regarding speed attainment. Unless it was initially built for higher speed running or subsequently adapted for such, the standard Routemaster wasn`t a fast bus. It didn`t need to be. Don`t forget that many central area routes went entirely along roads where the maximum speed limit was 30mph. There was nowhere along the 9 road where a greater speed was legal. Bus stops were so frequent and traffic often so heavy that going above 30mph was rare and schedules had to reflect this. Most RM`s and RML`s were capable of doing 40mph but in service rarely hit it with the exception of some routes that had outer London sections on faster roads and with greater distances between stops. But RM routes didn`t generally fall into this category. With a few exceptions such as the 134`s between the outskirts of Potters Bar and Hadley Highstone, where 40mph was attainable for around a mile or so. On the 237`s it was permissible to do 40mph over Hounslow Heath and if two consecutive request stops didn`t need to be served, the magic 40mph might just be reached but it was so unusual as to be exhilarating!

I know it seems embarrassingly slow to be doing 38mph on a Motorway with everything else belting past but in RM / RML terms it`s actually quite normal. When we took RM`s to a rally out of London we thought doing nearly 40mph over a distance was really going some. The Summer Sunday staff outings to the coast were generally constrained to sixty miles from base - unless extended with special permission - and also by the fuel range which was, in turn, relevant to speed. And as I`ve mentioned on here before, at Mortlake the three RM`s used for staff private hires had special tyres fitted to reflect longer distances constantly run at normal attainable top speed ie: 40mph max.

Whilst agreeing with Neil and Danny about designed speeds etc, "standard" RMs (even Mortlake's !) could go a bit faster than 40mph, not much and a top speed of 45mph was doing well, it all depends on how the fuel pump is set up and when the cut off cuts in, the RT and RM staff buses we had were not tuned or anything, but all could do over 40mph with a load.
I n France on our journeys to campaigns, we aim to do around 60kph - 38mph, for safety and fuel economy!

The problems of holding up traffic on roads is one we face on all our jobs, particularly with RTs, we avoid Motorways where possible due to our slow speeds on hills. The only thing that you can really do is to keep looking in the mirror for queues behind and find lay-bys to let cars pass if you can.

My bus number (if any): RTL 960, RM 1585, RMC 1485 and several RTs

Quite true, RM`s could do over 40mph and running back dead from Mortlake to Stamford Brook along the A316 proved that. The LT pump set up was, as I recall, to a maximum of 44mph. The occasional set up failure could produce some exciting results such as RM 873 at V (which was a horrible bus to drive) but would happily go way past 40mph. And I once had RM 2121 `off the clock` along the A316. That was almost frightening and I ran out of road before I ran out of speed! It, like RM 873, had a DPA pump. RT`s were quite capable of speed too. My school bus route involved a two mile section of the Barnet By Pass and in my usual seat behind the driver I often saw the speedo go beyond 50mph!

There's been discussions about this on here before. I've had RML2532 for a number of years now and about 10 years ago had the pump set to original Cummins spec of 2200rpm. The LT spec was about 1800 rpm which with a bus diff and 11R225 tyres gives about 38-42mph.

The extra 400 rpm gives a top speed of around 54mph and more down hill. This is ok and comfortable providing your gearbox, diff, prop shaft joints and suspension are in tip top condition; otherwise the vibration set up in the drive chain makes a very uncomfortable ride and will cause component failure.

I've actually had over 56 out of 2532 at times and it is comfortable at that speed. I used to run it almost every weekend from Ashford to London for private hires (not loaded) at that sort of speed with no problems.

But that is with a bus maintained to class 6 spec. With a bus on class 5 spec, I'd be very wary of driving at that sort of speed.

What you have to remember as well is that though the bus may be capable of going that speed, are the brakes capable of stopping it quickly from that speed?

Many years ago I had an Iveco DMS; we had that pump re-done to Iveco spec and it went up Reigate Hill at 38mph in 3rd gear; on the M23 it was capable of well over 70!

My bus number (if any): RM967 (Driver/Restoration consultant)