cav551:
Unfortunately my computer sound has packed up so it is difficult to comment at the moment. However the Bristol K series 4 and 5 speed boxes have a reputation for being ‘difficult’, the saying goes that once you think you have mastered them you find out that you were wrong. I can’t find the actual ratios anywhere but they are definitely wide ratio. 1st and 2nd are sliding mesh and have usually suffered from years of abuse and burred teeth. I’m sure we can all relate to a bad Fuller example which just won’t change cleanly. I haven’t driven a K5G but I have the more powerful K6A several times. However high an opinion of one’s ability, a surreptitious few miles of pratice is in order before picking up critical passengers. Jumping straight in on a bus change over leaves you open to rather unwelcome close scrutiny. Things are not helped by the cramped cab and the pedals being virtually under the seat. There is a definite knack to selecting 1st and letting the engine virtually stop and then acting very fast is the solution to a quiet change, trying to anticipate and giving it a bootful of revs while it is still going resonably well in second just doesn’t work.
Exactly which gear did he shift into at 2.35 was it 3rd to 2nd ?.
He obviously needed whatever the next gear down was to negotiate the junction safely anyway and to make the climb ahead regardless.
It shouldn’t have been going ‘reasonably’ well at that point in fact I’m surprised they haven’t put a stop sign on that junction.
So he had to drop down at least two gears on that approach from 3rd ? to 1st ? not just grab 2nd ? at the last minute on arrival at the junction which was too high in any event.
Going by the rest of the video it certainly looks like a driver who is averse to sequential downshifting in good time on the approach to hazards or holds it in the wrong too high gear until the verge of the engine running out of steam and then having to make a panic downshift as at 4.33.
Or as in the case of the roundabout no downshifts on the approach at all.
Which leaves the strange upshift made at the top of the hill before the descent into the crossing pedestrians and parked vehicles.I’m guessing he went to default reliance on the brakes at that point ?.
It’s obvious in the case of wide ratio gearboxes that the brakes sometimes need to be used to remove the momentum sufficient enough to get down to the correct road speed for the next lower gear down without leaving the downshift until the engine is labouring to an almost stop and as opposed to the unsympathetic rushed downshifts made at 4.33 and 7.30.
The technique shown on the approach in the Atki video seems relevant in all cases regardless of the closeness or otherwise of the ratio steps or constant v sliding ?.
I would never dream of driving anything in the way shown in the vid although might be wrong.
Froggy55:
0Bernard was better known for their trucks, but did also produced a few coaches, like this one which is waiting for its passengers in Nevers in the late '30s.
Bernard also produced stationary engines,very robust engines they were/are too Froggy.
David
I have two in the garage, one is being restored at the present time.
Pete.
I didn’t realise at first that the stationary engines you mention (and own, Pete), have nothing to do with Bernard trucks! The firm was known as “Bernard Moteurs”, and still exists. Firm history with the list of the main productions and a few pictures here (in French, of course): fr.wikipedia.org/wiki/Bernard_Moteurs
They still produce stationary engines for electric generators or gardening applications, and if ever you need spares, they’re still available: bernard-moteurs.com//produits
They had a factory in St-Satur, at 15 kms from my home; factory sold to Canadian, then Chinese, and finally closed down some 15 years ago.
Camions Bernard (Bernard Trucks) also produced stationary engines, but only big ones used to power generators for circuses or fun fairs.
Carryfast:
Exactly which gear did he shift into at 2.35 was it 3rd to 2nd ?.
He obviously needed whatever the next gear down was to negotiate the junction safely anyway and to make the climb ahead regardless.
It shouldn’t have been going ‘reasonably’ well at that point in fact I’m surprised they haven’t put a stop sign on that junction.
So he had to drop down at least two gears on that approach from 3rd ? to 1st ? not just grab 2nd ? at the last minute on arrival at the junction which was too high in any event.
Going by the rest of the video it certainly looks like a driver who is averse to sequential downshifting in good time on the approach to hazards or holds it in the wrong too high gear until the verge of the engine running out of steam and then having to make a panic downshift as at 4.33.
Or as in the case of the roundabout no downshifts on the approach at all.
Which leaves the strange upshift made at the top of the hill before the descent into the crossing pedestrians and parked vehicles.I’m guessing he went to default reliance on the brakes at that point ?.
It’s obvious in the case of wide ratio gearboxes that the brakes sometimes need to be used to remove the momentum sufficient enough to get down to the correct road speed for the next lower gear down without leaving the downshift until the engine is labouring to an almost stop and as opposed to the unsympathetic rushed downshifts made at 4.33 and 7.30.
The technique shown on the approach in the Atki video seems relevant in all cases regardless of the closeness or otherwise of the ratio steps or constant v sliding ?.
I would never dream of driving anything in the way shown in the vid although might be wrong.
I have looked at this again with sound: the driver obviously knows this vehicle well and what it is capable of. My guess is that this is not the first run of the day, a usual running day event would entail four ‘rounders’. The video is slightly misleading because the camera is considerably lower than the driver’s eye level and also about 2 feet behind him. What is not obvious without having driven a Bristol K is that the lever travel between 1st and 2nd is about two and a half times greater than it is between 3rd and 4th. The LW hits the governor much sooner than you possibly expect and is very slow to die down. The downchange to third at 3.52 is the earliest he can make it without exceeding maximum revs in the lower gear. As mentioned this driver knows the vehicle, both in the town and when meeting the bus coming the other way (at 1.45 and 5.00) he ■■■■■■ changes from 1st to 2nd, but he does more than that: just before changing he backs off the throttle to prevent the revs building up as soon as the clutch is depressed.
As for the approach to the first junction and hill he is in 3rd gear and changes down to 2nd. Given his better view he can see at 2.52 that the gradient eases very slightly from just before the lamp post on his left (from the pot hole on) at this point he knows he will get over the crest in that gear. Yes at first viewing it does look iffy I agree.The slightly larger capacity and freer revving AEC 7.7 in a K6A will respond to a more press-on driving style if you aim to hit maximum revs in the lower gear, but this video reinforces the saying that ‘you can’t hurry a Gardner’. The nearest you can get to it is at 7.33.
Carryfast:
Exactly which gear did he shift into at 2.35 was it 3rd to 2nd ?.
He obviously needed whatever the next gear down was to negotiate the junction safely anyway and to make the climb ahead regardless.
It shouldn’t have been going ‘reasonably’ well at that point in fact I’m surprised they haven’t put a stop sign on that junction.
So he had to drop down at least two gears on that approach from 3rd ? to 1st ? not just grab 2nd ? at the last minute on arrival at the junction which was too high in any event.
Going by the rest of the video it certainly looks like a driver who is averse to sequential downshifting in good time on the approach to hazards or holds it in the wrong too high gear until the verge of the engine running out of steam and then having to make a panic downshift as at 4.33.
Or as in the case of the roundabout no downshifts on the approach at all.
Which leaves the strange upshift made at the top of the hill before the descent into the crossing pedestrians and parked vehicles.I’m guessing he went to default reliance on the brakes at that point ?.
It’s obvious in the case of wide ratio gearboxes that the brakes sometimes need to be used to remove the momentum sufficient enough to get down to the correct road speed for the next lower gear down without leaving the downshift until the engine is labouring to an almost stop and as opposed to the unsympathetic rushed downshifts made at 4.33 and 7.30.
The technique shown on the approach in the Atki video seems relevant in all cases regardless of the closeness or otherwise of the ratio steps or constant v sliding ?.
I would never dream of driving anything in the way shown in the vid although might be wrong.
I have looked at this again with sound: the driver obviously knows this vehicle well and what it is capable of. My guess is that this is not the first run of the day, a usual running day event would entail four ‘rounders’. The video is slightly misleading because the camera is considerably lower than the driver’s eye level and also about 2 feet behind him. What is not obvious without having driven a Bristol K is that the lever travel between 1st and 2nd is about two and a half times greater than it is between 3rd and 4th. The LW hits the governor much sooner than you possibly expect and is very slow to die down. The downchange to third at 3.52 is the earliest he can make it without exceeding maximum revs in the lower gear. As mentioned this driver knows the vehicle, both in the town and when meeting the bus coming the other way (at 1.45 and 5.00) he ■■■■■■ changes from 1st to 2nd, but he does more than that: just before changing he backs off the throttle to prevent the revs building up as soon as the clutch is depressed.
As for the approach to the first junction and hill he is in 3rd gear and changes down to 2nd. Given his better view he can see at 2.52 that the gradient eases very slightly from just before the lamp post on his left (from the pot hole on) at this point he knows he will get over the crest in that gear. Yes at first viewing it does look iffy I agree.The slightly larger capacity and freer revving AEC 7.7 in a K6A will respond to a more press-on driving style if you aim to hit maximum revs in the lower gear, but this video reinforces the saying that ‘you can’t hurry a Gardner’. The nearest you can get to it is at 7.33.
I think I can understand the problems presented by the seeming too wide ratio box.
But firstly the junction at 2.30 followed by the climb is an at least one gear lower situation than the one which was obviously pre planned for and selected seemingly, as I thought, 3rd to 2nd.
When it should have been back off/brake it down for the downshift from 3rd to 2nd at around 2.20 then repeat at around 2.30 at which point the vehicle is now in first at a much slower approach speed ready for the junction and the climb at around 2.32.Bearing in mind that the gear also needed to be the correct one to pull away in if the junction had required him to halt anyway.
IE that had to be a two downshift approach as opposed to the excessively high gear and approach speed chosen.If for no other reason to assess the blind junction to the left before the right turn let alone the climb after it.
As for what followed again every situation seems to have been approached in at least one gear higher than it should have been at the time.Or in the case of the roundabout at 10.08 that looks like he approached it in 4th ? rather than downshifting it to 3rd ? at the brow of the incline at 9.50 then using the resulting engine braking and the brakes to bring the speed down again for a downshift to 2nd ? at 10.02 by the tree on the right.Bearing in mind that is a blind roundabout entry he doesn’t know what’s entering it from the right.
As for the right turn at 7.33 that looked like either he downshifted from 4th and made the turn in 3rd ? gear.Couldn’t possibly have block changed it from 4th to 1st ?. Either way another poor show.
When that approach should have been along the lines of the Atki video.
That was easily a two downshift approach starting by backing off and braking it down at 7.25 at the latest then downshift from 4th ? to 3rd ? at 7.28 just before the road signage and slow sign then bring it down again for another downshift from 3rd ? to 2nd ? at 7.33.You could hear that the box protested at that downshift made too late at a too high road speed and a too high gear at that on the exit 3rd ? because he didn’t give himself enough time to drop sufficient gears on the approach for the situation.
My guess is that there would have been enough there to fail the test on approach and use of gears.Having said that examiners brought up with brakes to slow gears to go who knows.
TruckNetUK . Old Time Lorries . Buses,Motorcoaches & Lorries,Pages 66,67. Bristol K6B/ECW Double Decker Omnibus,KUO 972 Film - Videos .
St.Patrick’s Day,Wednesday,17th March,2021.
CAV551:
There doesn’t seem to be much video of vehicles through the windows posted so, since there has been some comment on another thread, here is one of a Bristol KS5G from the front n/s seat. There is regretably some distraction from passengers talking however a good apprecitation can be had of driving a fully loaded underpowered vehicle with sliding mesh 1st and 2nd gears along a challenging route. The driver has got ■■■■■■ changes off to a T. Volume required.
Thanks for the above John G.Lidstone film-video I’ve linked another John G.Lidstone film-video in this post;the film has been divided in to three parts (for whatever
reason or reasons) by John Lidstone on YouTube:-
Part 1.
The first part of the film-video shows preserved Bristol K6B/ECW Double Decker Bus,KUO 972,Western National,959 giving a joy ride to a full load of passengers - many
of whom are Bus & Motorcoach Enthusiasts,going up a fairly steep hill and coming to an ungainly halt - because it’s engine needed a major re-build in my opinion youtube.com/watch?v=5wLB-ap90lw
Part 2.
Part two shows the passengers walking up the hill as the driver tries to get the Bristol to proceed up that hill…even without it’s passengers the Bristol struggles
to go up the hill - a sure sign that all is not well with the engine because it’s seriously down on the manufacturers’ specified power and torque !
It is obvious that outwardly (the exterior of the bus) and inwardly (the interior of the bus ie.passenger areas and - from what can be seen of it - the driver’s cab)
this Bristol has been beautifully restored. No doubt the Bristol AVW Diesel Engine will probably look as polished as the rest of the bus,but it’s polished appearance
is almost certainly hiding the real possibility that this engine is in need of a major re-build: re-grinded crankshaft;new main crankshaft,big end and little end
re-built this engine will be as good as new and fully perform to Bristol’s specifications …and able to go up that hill without any trouble!
In the comments section of this YouTube film-video John Lidstone virtually makes every excuse under the sun as to why this Bristol failed to go up that hill:-
QUOTE:The Bristol AVW engine does not have good torque at low revs and the driver, who was very capable, just got caught out by not quite changing down early enough and with the gradient, the bus didn’t have the guts to keep going without having to stop. That was also difficult to make a standing start on a very steep gradient that tested clutch and engine to the max. AVWs sing along better at top end than a Gardner does but they lack pulling power at low revs.UNQUOTE.
He fails to consider that the engine probably needs a major re-build. The Bristol was in service with Western National from 1950 to 1970.How many major engine
re-builds did it have during this period? R & W Pierce, Borough Green (contractor) was the owner of KUO 972 from April 1970 to 1982,it was then sold to bus,
motorcoach and lorry preservationist,David Hoare,of Chepstow. How many major engine re-builds has it had since 1970?
I’ve come across hundreds of preserved motor vehicles of all types and kinds over the years. Some have had ‘from the ground up last nut and bolt restorations’,
while others have had their cabs,bodies,whatever,restored,but the engines and other mechanical units,if in running order,have been left alone,irrespective of
whether the engine needed a major re-build or not
John Lidstone says that the Bristol AVW Diesel Engine does not have good torque at low revolutions-per-minute. Let’s compare Bristol AVW and Gardner 5LW & 6LW
NOTE:Among the things that are clear is that all these of these engines were grossly underpowered!
John Lidstone is obviously wrong: the Gardner 5LW in both original and K versions is both out-powered and out-torqued by
the Bristol AVW engine and produces it’s torque @ 1200 RPM which is lower than the 1300 RPM of both the Gardner 5LWK and the 6LWK.
Where’s both the Gardner original 6LW and 6LWK produce only marginally more power and torque than the Bristol AVW engine.
Here is another comment from the above YouTube page:-
QUOTE:
Rolin224 . Something wrong here.A K6B ought to be able to climb a mountain, as long as it has all day to do it. Either the engine is seriously down on power, or the gearing has been raised to give a higher top speed.A too late “into first” didnt help either.UNQUOTE.
Rolin224 is right!
Bristol was a highly reputable manufacturer of buses,motorcoaches and lorries who built these types of motor vehicle mainly for the State-owned bus,motorcoach
and lorry operators in the Post-War years,and would never knowingly produce motor vehicles that,when fully loaded,were not capable of climbing hills on roads
of all tractable gradients from the bottom to the top!
Since this film-video has been made in 2014 I hope that this Bristol K6B,KUO 672 has now had the major engine re-build that it deserved to have had!
A Daimler Fleetline bus that has been rebuilt as a single decker, after an accident.
I think the original bodywork was by Northern Counties, and the bus is on route 477
from Bury to Summerseat. Details of the accident are not known to me. Not my picture.
Here is another comment from the above YouTube page:-
QUOTE:
Rolin224 . Something wrong here.A K6B ought to be able to climb a mountain, as long as it has all day to do it. Either the engine is seriously down on power, or the gearing has been raised to give a higher top speed.A too late “into first” didnt help either.UNQUOTE.
Rolin224 is right!
Bristol was a highly reputable manufacturer of buses,motorcoaches and lorries who built these types of motor vehicle mainly for the State-owned bus,motorcoach
and lorry operators in the Post-War years,and would never knowingly produce motor vehicles that,when fully loaded,were not capable of climbing hills on roads
of all tractable gradients from the bottom to the top!
VALKYRIE
I’ve reached the conclusion of the perfect storm of at best under powered engines, of unknown condition, totally unsuitable final drive ratio for the terrain, silly wide ratio gearboxes, drivers who have an idea ‘how’ to shift gears but absolutely no idea of ‘when’ to shift em and which ones they need to be using at any particular point even if they had them all to use. .
Back to some sanity.That thing sounds bleedin lovely.Slightly late at 1.54 but unlike the bus it just laughed at it.
Ray Smyth:
A Daimler Fleetline bus that has been rebuilt as a single decker, after an accident.
I think the original bodywork was by Northern Counties, and the bus is on route 477
from Bury to Summerseat. Details of the accident are not known to me. Not my picture.
Ray Smyth:
A Daimler Fleetline bus that has been rebuilt as a single decker, after an accident.
I think the original bodywork was by Northern Counties, and the bus is on route 477
from Bury to Summerseat. Details of the accident are not known to me. Not my picture.
It does have a truncated look, doesn’t it?
This info was on another forum:
"Leyland Fleetline 1697 was a double deck until the early eighties. After an encounter with Wargrave railway bridge at Newton-le-Willows parted the upper deck from the rest of the bus it was thought that its future was doomed.
However, a need for a short single deck at Bury depot for the Summerseat service led to GMT’s engineers to look into using the perfectly serviceable lower deck as the basis of a single deck for the above purpose. Strathclyde PTE used similar converted Atlanteans on an inter station link service in Glasgow and one was inspected [but not used in service] by GMT before making a decision on the accident damaged Fleetline.
The work was authorised and the conversion was carried out by Northern Counties. An extra emergency window was fitted to the nearside and shrouds added over the rear ‘pods’ to give the body strength."
Ray Smyth:
A Daimler Fleetline bus that has been rebuilt as a single decker, after an accident.
I think the original bodywork was by Northern Counties, and the bus is on route 477
from Bury to Summerseat. Details of the accident are not known to me. Not my picture.
It does have a truncated look, doesn’t it?
This info was on another forum:
"Leyland Fleetline 1697 was a double deck until the early eighties. After an encounter with Wargrave railway bridge at Newton-le-Willows parted the upper deck from the rest of the bus it was thought that its future was doomed.
However, a need for a short single deck at Bury depot for the Summerseat service led to GMT’s engineers to look into using the perfectly serviceable lower deck as the basis of a single deck for the above purpose. Strathclyde PTE used similar converted Atlanteans on an inter station link service in Glasgow and one was inspected [but not used in service] by GMT before making a decision on the accident damaged Fleetline.
The work was authorised and the conversion was carried out by Northern Counties. An extra emergency window was fitted to the nearside and shrouds added over the rear ‘pods’ to give the body strength."
Thank you for the Fleetline info Dennis. The location of its " Accident " is about 8 miles from here where I live. Cheers, Ray.
Here is another comment from the above YouTube page:-
QUOTE:
Rolin224 . Something wrong here.A K6B ought to be able to climb a mountain, as long as it has all day to do it. Either the engine is seriously down on power, or the gearing has been raised to give a higher top speed.A too late “into first” didnt help either.UNQUOTE.
Rolin224 is right!
Bristol was a highly reputable manufacturer of buses,motorcoaches and lorries who built these types of motor vehicle mainly for the State-owned bus,motorcoach
and lorry operators in the Post-War years,and would never knowingly produce motor vehicles that,when fully loaded,were not capable of climbing hills on roads
of all tractable gradients from the bottom to the top!
VALKYRIE
I’ve reached the conclusion of the perfect storm of at best under powered engines, of unknown condition, totally unsuitable final drive ratio for the terrain, silly wide ratio gearboxes, drivers who have an idea ‘how’ to shift gears but absolutely no idea of ‘when’ to shift em and which ones they need to be using at any particular point even if they had them all to use. .
Back to some sanity.That thing sounds bleedin lovely.Slightly late at 1.54 but unlike the bus it just laughed at it.
A single deck bus of " Warringtons Bus " waiting to turn right from Ormskirk Road, A577
into Fleet Street at Pemberton traffic lights. It is on circular route 641, this journey takes
about 1 hour and 25 minutes, but is never more than 5 miles from Wigan bus station.
I see that bus chassis production has returned to Leyland with ADL now having their bus chassis being assembled there. I guess that this is temporary but I don’t know how much available space there is at Falkirk anyway to add on the chassis production line. Just the stores alone would take up a large portion of the space needed.
Dennis Javelin:
I see that bus chassis production has returned to Leyland with ADL now having their bus chassis being assembled there. I guess that this is temporary but I don’t know how much available space there is at Falkirk anyway to add on the chassis production line. Just the stores alone would take up a large portion of the space needed.
Chassis assembly has been undertaken at Leyland for several years now.
The buildings area of the former Leyland Truck & Bus Technical Centre became an Industrial Estate. The firm assembling the chassis (amongst other things) is M I Vehicle Integration Ltd who occupy part of the Estate.
Work has recently started on the open land where the Test Track area of the Technical Centre was located to build a further Industrial Estate.
Dennis Javelin:
I see that bus chassis production has returned to Leyland with ADL now having their bus chassis being assembled there. I guess that this is temporary but I don’t know how much available space there is at Falkirk anyway to add on the chassis production line. Just the stores alone would take up a large portion of the space needed.
Chassis assembly has been undertaken at Leyland for several years now.
The buildings area of the former Leyland Truck & Bus Technical Centre became an Industrial Estate. The firm assembling the chassis (amongst other things) is M I Vehicle Integration Ltd who occupy part of the Estate.
Work has recently started on the open land where the Test Track area of the Technical Centre was located to build a further Industrial Estate.
I knew that the right hand drive DAF’s were assembled here and some other export stuff but not bus chassis though (as far as I know) so I thought this would be of interest.
I’ve linked another John G.Lidstone film-video in this post;the film has been divided in to three parts (for whatever
- because it’s engine needed a major re-build in my opinion 
…and able to go up that hill without any trouble! 
R & W Pierce, Borough Green (contractor) was the owner of KUO 972 from April 1970 to 1982,it was then sold to bus,
.
