Electronically-controlled air suspension VS air bellows...
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I always thought electronically-controlled air suspension gives the best ride quality..like in Mercedes S-Class with air suspension..it's like magic carpet ride..
But those buses with electronically controlled air suspension in SG like the Volvo B9TL/B10TL, and the Scania K230UBs, their ride quality seems so-so only..
Of course, when compared to other buses like the B10Ms (Mk2, 3 and 4), the Scania N113CRB and the DDs like LO3x and VO3x..the B9TL/B10TLs and K230UBs have a smoother ride..
But when compared to the Merc O.405, i think the 0.405's ride is even better! Even more supple..
But of course, the three buses with electronically-controlled air suspension I've mentioned (B9TL, B10TL, K230UB) has some advantages that other buses don't have..like less lean angles when making turns..especially with the B9TL, it's so neutral and leans so little during a turn..and it doesn't squat and dive as much during acceleration and deacceleration..
The only other bus with electronically-controlled air suspension that I think matches the O.405 in ride quality is the B10BLE I think..
But one thing about the O.405 though, it's ride is smooth and supple definitely..but when the road is bumpy, it's suspension gets caught out and gets a little willowy..
Comments? -
For me, when it comes to suspension ride comfort, i'll classify broadly into just leaf-spring or air-suspension.
For superior ride comfort, it'll take air-suspension.
Ranked from best to worse in suspension ride comfort among the common models here, I'll put it as (best) M-B O 405, O 405 G, Volvo B9TL, Volvo/Leyland Olympians, Scania K230UB, Scania N113CRB, Volvo B10M Mk.4, Mk.2 then Mk.3 (worse !)
I notice the suspension on O 405 & even O 305 while overall is very comfortable can get somewhat bouncy when over excessive undulations. Same too i recall among the other older M-B models like on OH 1627 L.
However, the newer generation M-B O 500 like 1725 etc. tends to be remarkably very stable (with hardly any bounciness left-right or frontwards-rearwards !) whether doing 50 or 100 km/h & just as comfortable as the older M-B air-suspended models. I think on this model you can hold your cup of coffee with the least chances of spillage even @ 120 km/h !
Dislike though is that the suspension is the noisier type, something like on the Scanias BUT without the inferior comfort levels from those.Originally posted by alleggerita:I always thought electronically-controlled air suspension gives the best ride quality..like in Mercedes S-Class with air suspension..it's like magic carpet ride..
But those buses with electronically controlled air suspension in SG like the Volvo B9TL/B10TL, and the Scania K230UBs, their ride quality seems so-so only..
Of course, when compared to other buses like the B10Ms (Mk2, 3 and 4), the Scania N113CRB and the DDs like LO3x and VO3x..the B9TL/B10TLs and K230UBs have a smoother ride..
But when compared to the Merc O.405, i think the 0.405's ride is even better! Even more supple..
But of course, the three buses with electronically-controlled air suspension I've mentioned (B9TL, B10TL, K230UB) has some advantages that other buses don't have..like less lean angles when making turns..especially with the B9TL, it's so neutral and leans so little during a turn..and it doesn't squat and dive as much during acceleration and deacceleration..
The only other bus with electronically-controlled air suspension that I think matches the O.405 in ride quality is the B10BLE I think..
But one thing about the O.405 though, it's ride is smooth and supple definitely..but when the road is bumpy, it's suspension gets caught out and gets a little willowy..
Comments? -
i would put Dennis and Leyland make buses down at bottom of air suspensions list. i have this impression so far, of british made buses having lousy lateral suspension control. such that (especially on dennis trident SG) u rock to and fro left and right ways when bus gg on road.
or could be our roads most of them slope leftwards or rightwards to let rainwaters drain in this humid n wet country causing the bias
ZYX -
Agreed . Thier suspensions aren't that good IMO .Originally posted by ZYX2005:i would put Dennis and Leyland make buses down at bottom of air suspensions list. i have this impression so far, of british made buses having lousy lateral suspension control. such that (especially on dennis trident SG) u rock to and fro left and right ways when bus gg on road.
or could be our roads most of them slope leftwards or rightwards to let rainwaters drain in this humid n wet country causing the bias
ZYX
Next on the list are Scania city buses . The coaches are fine , but their city buses suspension really suck. First the N113CRBs , then the L113CRLs , can't say abt the L94UB since i havent take them before and the latest K230UB .
The best would still be Volvo and MB . -
Is it? I don't really think Leyland/Volvo Olympians have a good ride..Originally posted by Scania N113CRB luver:Agreed . Thier suspensions aren't that good IMO .
Next on the list are Scania city buses . The coaches are fine , but their city buses suspension really suck. First the N113CRBs , then the L113CRLs , can't say abt the L94UB since i havent take them before and the latest K230UB .
The best would still be Volvo and MB .
Maybe because the suspension of VO3x/LO3x will rattle a lot especially the older ones..maybe the rattling will give me an impression that the suspension ain't that supple..and it seriously makes me feel for the health of the bus..
Same for a few B10M Mk4 DM on svc. 27..have seriously bad case of rattling suspension at the rear axle..sounds like the whole rear axle might give way and fall off..
And does anyone have this impression that the suspension travel of most Volvo buses very minimal? Like when it goes over bumps, it feels like the suspension can't compress enough..O405's suspension travel seems very generous..so much so that it bobbles when the road gets rough..
And for Volvos, I rank B9TL as the most comfortable and the B10M Mk4 DM3500 second..but I remember 2734 on svc. 27 (and a few other DM3500s) had a bobbling front axle when stationary..you can hear hisses and the front suspension will lower itself a bit..then hisses again and it raises back up..is it a problem or is it due to some settings? -
Yes, i forgotten about the Dennis Tridents here & their 'left-right' movements ! Find it somewhat unique in the air-suspended category such undesirable behavior. As for the air-suspended Leylands here such 'left-right' movements not so obvious however.
But i recall sitting on the spring-suspended Leyland Atlantean gives one the shake all over, especially on the upper deck !! More difficult to read newspaper when moving on this !Originally posted by ZYX2005:i would put Dennis and Leyland make buses down at bottom of air suspensions list. i have this impression so far, of british made buses having lousy lateral suspension control. such that (especially on dennis trident SG) u rock to and fro left and right ways when bus gg on road.
or could be our roads most of them slope leftwards or rightwards to let rainwaters drain in this humid n wet country causing the bias
ZYX -
I encountered the same observations regarding the Scanias.
While i notice all the Scanias i sat on have noisy suspensions, the lower floor city-bus models tend to have a 'rough' ride with minimal damping ?!
Seems no improvements whether on the 1989 or 2007 models. Perhaps it's not an area of priority for them to work on ??
However on the high-floor Scanias the suspension ride comfort is far better but still not quite as overall comfortable as on the MAN & M-B, in that order.
M-B has been very consistently superior in this area, whether in the spring or air-suspended categories. Volvo has made huge improvements in this area, from the B10M era to B9TL although i believe the mid-engine placement on the B10M is a major reason for the over light hence lively rear end, thus resulting in poor suspension comfort especially over there.Originally posted by Scania N113CRB luver:Agreed . Thier suspensions aren't that good IMO .
Next on the list are Scania city buses . The coaches are fine , but their city buses suspension really suck. First the N113CRBs , then the L113CRLs , can't say abt the L94UB since i havent take them before and the latest K230UB .
The best would still be Volvo and MB . -
The rattling i believe is coming from the wheels not the suspension.
Wheel-tyre maintenence due ?
Hissing is the sound of the compressed air. Perhaps that vehicle has kneeling function which lowers the front region for lower height boarding ?
Agree with your observations the suspension travel seems less on the Volvo & more on the M-B. On the Volvo the 'landing' tends to be harder while on the M-B it's softer.Originally posted by alleggerita:Is it? I don't really think Leyland/Volvo Olympians have a good ride..
Maybe because the suspension of VO3x/LO3x will rattle a lot especially the older ones..maybe the rattling will give me an impression that the suspension ain't that supple..and it seriously makes me feel for the health of the bus..
Same for a few B10M Mk4 DM on svc. 27..have seriously bad case of rattling suspension at the rear axle..sounds like the whole rear axle might give way and fall off..
And does anyone have this impression that the suspension travel of most Volvo buses very minimal? Like when it goes over bumps, it feels like the suspension can't compress enough..O405's suspension travel seems very generous..so much so that it bobbles when the road gets rough..
And for Volvos, I rank B9TL as the most comfortable and the B10M Mk4 DM3500 second..but I remember 2734 on svc. 27 (and a few other DM3500s) had a bobbling front axle when stationary..you can hear hisses and the front suspension will lower itself a bit..then hisses again and it raises back up..is it a problem or is it due to some settings? -
Definitely not from rims and tyres..I can't see how the rims and tyres will cause rattling noise..Originally posted by hseochin:The rattling i believe is coming from the wheels not the suspension.
Wheel-tyre maintenence due ?
Hissing is the sound of the compressed air. Perhaps that vehicle has kneeling function which lowers the front region for lower height boarding ?
Agree with your observations the suspension travel seems less on the Volvo & more on the M-B. On the Volvo the 'landing' tends to be harder while on the M-B it's softer.
Sounds like it's coming from the whole suspension subframe more..
And the problem with the DM3500, I doubt it's due to the kneeling function..it's like the electronically-controlled front air suspension can't control itself more like..it sometimes goes up, sometimes go down..when you sit somewhere near or over the front axle, it can get a little dizzy..
And it only happens when the bus is stationary, whether the door is opened or not..this happens even at traffic lights.. -
Ever seen before how a rolling disc or hoop wobble when rolling? Thats how a wheel wobbles , but at higher speed.Originally posted by alleggerita:Definitely not from rims and tyres..I can't see how the rims and tyres will cause rattling noise..
Sounds like it's coming from the whole suspension subframe more..
And the problem with the DM3500, I doubt it's due to the kneeling function..it's like the electronically-controlled front air suspension can't control itself more like..it sometimes goes up, sometimes go down..when you sit somewhere near or over the front axle, it can get a little dizzy..
And it only happens when the bus is stationary, whether the door is opened or not..this happens even at traffic lights.. -
theres a certain DM3500 on sv27
dunno whther its still there anot
bc got out to tap card b4 gg off or sth
the bus normal height
then bus keeps hissing loudly, the front go lower n lower n lower.
when he came back
he walk right onto the bottom step, like wtf..
as for B10M's. there sure is a suspension noise
but not so much for DM MKIV
its much more for MK III's
especially one of them on sv89
the rear suspension is not only HARD..
every little bump it goes gong..
same for batch 1&2 VO3X and LO3X's
tag axle bangs around loudly..
maybe its cos BC's chiong over humps?
took 161 just now, bc goes slowly over front axle
then accelerates and bumps right over the tag and rear axle. hmm. -
Yeah. I still think the rattling noise comes from the whole suspension frame. It's common on B10M Mk3s and some Mk4 too. Even a few DM3500 is suffering from it!Originally posted by SBS7484P:theres a certain DM3500 on sv27
dunno whther its still there anot
bc got out to tap card b4 gg off or sth
the bus normal height
then bus keeps hissing loudly, the front go lower n lower n lower.
when he came back
he walk right onto the bottom step, like wtf..
as for B10M's. there sure is a suspension noise
but not so much for DM MKIV
its much more for MK III's
especially one of them on sv89
the rear suspension is not only HARD..
every little bump it goes gong..
same for batch 1&2 VO3X and LO3X's
tag axle bangs around loudly..
maybe its cos BC's chiong over humps?
took 161 just now, bc goes slowly over front axle
then accelerates and bumps right over the tag and rear axle. hmm.
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The worst suspension I have tried comes from the tridents.
All the small bumps amplified in all directions.
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That's fairly common to see low-rider MKIV DM3500s....but have you seen a DM3500 MKIV going around like its on stilts? Well I have.
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And they have this weird vibration when the bus is about to come to a halt. Like it's going to stall.Originally posted by SBS3625D:The worst suspension I have tried comes from the tridents.
All the small bumps amplified in all directions. -
nope, those DM3500s with bobbling front axles I've encountered is not in low-rider mode. They are at a normal ride height.Originally posted by SBS3625D:That's fairly common to see low-rider MKIV DM3500s....but have you seen a DM3500 MKIV going around like its on stilts? Well I have. -
That. I asked before and what I heard was that it was due to the engine being disconnected or something.....not sure.Originally posted by alleggerita:And they have this weird vibration when the bus is about to come to a halt. Like it's going to stall. 
This also has to do with the pause everytime the BC sets to N. -
yeah.. dennis tridents.. going to stop alr, then drrrrrrrnnng
everything rattles like gonna stall engine.. LOL.
maybe its the gearbox, cos VSO rpm oso drop very low before stopping, but not so bad till it sounds like going to stall
then the suspension is urgh..
most dd sit upstairs is quite comfy this one is upstairs equally jerky..
but saving grace
at least it doesent have obnoxious suspension noises.. but its jus a matter of time -
sm LO3X/VO3X will rattle tag axle so badly can hear from outside the bus as it goes past, a loud squeaking, then clanging noise..
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This reminds me of the VSOs and gassies . Sometimes when they are going to stop , theres a vibration . Suspect its coming from the brakes . Wonder if they have disc brakes . Some disc brakes have this problem .Originally posted by SBS7484P:yeah.. dennis tridents.. going to stop alr, then drrrrrrrnnng
everything rattles like gonna stall engine.. LOL.
maybe its the gearbox, cos VSO rpm oso drop very low before stopping, but not so bad till it sounds like going to stall
then the suspension is urgh..
most dd sit upstairs is quite comfy this one is upstairs equally jerky..
but saving grace
at least it doesent have obnoxious suspension noises.. but its jus a matter of time -
Gassies? You mean buses with electronically-controlled air suspension? Does the Dennis Trident uses electronically-controlled air-suspension or just air bellows?Originally posted by Scania N113CRB luver:This reminds me of the VSOs and gassies . Sometimes when they are going to stop , theres a vibration . Suspect its coming from the brakes . Wonder if they have disc brakes . Some disc brakes have this problem .
And I've only seen B9TLs having front disc brakes..VSO not very sure..can't see clearly..LO3x/VO3x confirm not disc brakes at the front.. -
At here , gassies = Volvo B10BLE CNG .Originally posted by alleggerita:Gassies? You mean buses with electronically-controlled air suspension? Does the Dennis Trident uses electronically-controlled air-suspension or just air bellows?
And I've only seen B9TLs having front disc brakes..VSO not very sure..can't see clearly..LO3x/VO3x confirm not disc brakes at the front.. -
Oops..my bad..Originally posted by Scania N113CRB luver:At here , gassies = Volvo B10BLE CNG . -
VSO have, VO,LO maybe not really,
dennis tridents = airbellows only, the buses dun have electronic control, cos they dont shift around at stoplights.
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The reason the B9TL doesn't dip under braking is because of the Electronic Brake Distribution which means that the force of braking is equal across the front and rear axles, which still factoring forces of inertia. I prefer less complicated air-suspension because they don't tend to self level all the time.