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Old 30th July 2007, 21:46   #16
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Originally Posted by Mpower View Post
All Class 8 trucks in the US and Western Europe are 100% air suspension in the rear tandem axle and all trailer axles. Only the front suspension is mechanical. Intercity coaches and large RV are also air. Next time you see a big rig, take a peek
You mean the Semi's? Ok that wont be difficult!! I will surely take a peek and post pics!
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Old 30th July 2007, 22:14   #17
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Originally Posted by narayan View Post
i think gas filled shocks may not be same as air suspension bcos even bikes like pulsar and enfied have those..

I don't know about enfield but the so called gas gilled shock absorbers in pulsar is a scam. I had a pulsar without it and currently own one with it and I feel the older one is better .

Bala
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Old 30th July 2007, 22:16   #18
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Quote:
Originally Posted by Mpower View Post
All Class 8 trucks in the US and Western Europe are 100% air suspension in the rear tandem axle and all trailer axles. Only the front suspension is mechanical. Intercity coaches and large RV are also air. Next time you see a big rig, take a peek

Not in India for a long time
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Old 31st July 2007, 12:51   #19
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Most of the mercs,audis have air suspension . Advantages of air suspension is

you can increase the ride height

you can either make the suspension stiffer or softer \

there is less of mechanical wear and tear -

disadvantages are

needs a compressor to drive the air baloons

Needs frequent servicing /changing of the baloons /they get punctured easily

Needs a fair bit of electornics to control the suspension .
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Old 31st July 2007, 12:57   #20
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Quote:
Originally Posted by fiery enzyme View Post
I don't know about enfield but the so called gas gilled shock absorbers in pulsar is a scam. I had a pulsar without it and currently own one with it and I feel the older one is better .

Bala

are u sure , u have not put on too much weight from the time u used the earlier pulsar - that cud negate the effect of the gas filled units
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Old 31st July 2007, 13:15   #21
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Utility-wise air suspensions are a direct fit into luxury cars where plush ride is the car' USP. Personally I prefer my suspensions to be stiff and great handlers instead
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Old 6th August 2007, 19:33   #22
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Originally Posted by 1100D View Post
You mean the Semi's? Ok that wont be difficult!! I will surely take a peek and post pics!
pics posted as promised in this thread

http://www.team-bhp.com/forum/522877-post185.html
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Old 6th August 2007, 21:17   #23
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BMW now has an R series DP bike (motorcycle) with rear air suspension. No compressor..need to top up just like your tires.
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Old 6th August 2007, 23:08   #24
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Air suspensions cannot withstand sustained hard riding on bad roads(the bellows fail after some time). They are primarily built for a pliant ride on good roads, not the lunar surfaces that we have as roads.

On cars, they would drive up the costs too much and be cause of so much service woes for the manufacturer.
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Old 7th January 2008, 13:34   #25
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After hearing of my cousin's air-suspension woes (S-Class), I am glad they aren't standard on all cars yet. Forget cost and complexity, they really need to work on reliability first.
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Old 7th January 2008, 14:39   #26
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Off-topic:

Arjun, the indigenous tank developed by our DRDO, has air suspension (hydro-pneumatic) too. IIRC, it's the only MBT in the world with this type of suspension. It is known to be problematic.
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Old 8th January 2008, 13:51   #27
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Well, some older cars were made with air suspension. One of my uncles had bought one such car second-hand through his father-in-law (who operated a garage). Unfortunately, I dont recall the make as this incident relates to 20 years ago.

Well, the shock absorbers/ suspension needed to be topped up (like the tyres) every fortnight or so. The air pressure required was 200 PSI (if I recall correctly). And petrol bunks do not have this pressure. So he had to specially find a guy willing to fill that air at that pressure and ofcourse that chap charged for his premium service.

Eventually, he sold off the car.
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Old 9th January 2008, 01:28   #28
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My versions in bold

Quote:
Originally Posted by narayan View Post
i think gas filled shocks may not be same as air suspension bcos even bikes like pulsar and enfied have those..

Here the springs continue to exists, only the damper charge is Nitrogen or any other inert Gas instead of oil.

i think air suspension refers to an air balloon/membrane on which the body floats . this holds air and the air itself acts as the spring unline a gas filled shocks where the gas provides the damping alone...

Here the spring is replaced by air bellows, which act as both the spring and the damper
Quote:
Originally Posted by fiery enzyme View Post
I don't know about enfield but the so called gas gilled shock absorbers in pulsar is a scam. I had a pulsar without it and currently own one with it and I feel the older one is better .

Bala

I would like to offer a small clarification here:

A typical suspension setup consists of two key components.
One is the Spring (Leaf/Coil in the Normal sense), which effectively takes the entire load( sprung mass of the vehicle).
In rough patches, the flex of the spring will provide a better ride than a rigid direct connection, by absorbing the shocks (by effecting changes in the potential energy of the spring)
Second compoent is the Damper, whose function is to control(dampen) the oscillations which would result, in this Energy conversion at the spring.(Before i get too technical, let me also say that, the main function of the damper is to act as an energy dissipator)


In an Air-matic suspension(MB) both the spring and damper has been taken care of , by variable air bellows.The main advantage here is that we have infinite no: of spring ratios that too electronically controlled , so more pliant ride (analogous to CVT Vs Normal gearshift)

And hence the cost factor is prohibitive. And more over the air bellows are akin to the one you can notice in many a musical instruments(although much more robust polymer rubbers), Steel coil springs have, on any given day more life and resilience and hence reliability

In a nitrox( or whatever as in those bikes) , The difference lies in the damper alone and the springs are not done away with.Only the damping fluid here is Nitrogen or some inert gas instead of our normal oil.


Hope this clears the confusion.Sorry if it was too technical , I simply couldn't help it.
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Old 9th January 2008, 07:25   #29
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Quote:
Originally Posted by aravindwarrier View Post

And hence the cost factor is prohibitive. And more over the air bellows are akin to the one you can notice in many a musical instruments(although much more robust polymer rubbers), Steel coil springs have, on any given day more life and resilience and hence reliabilit
Hope this clears the confusion.Sorry if it was too technical , I simply couldn't help it.
The Merc air suspension very much has a separate damper.

Last edited by GTO : 9th January 2008 at 10:02.
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Old 9th January 2008, 11:11   #30
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Quote:
Originally Posted by Mpower View Post
The Merc air suspension very much has a separate damper.
Is it so ? Can u provide some more detail
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