[OSH]

I travel daily by BEST,but a few days back i came across something quite unusual.

The bus(Ashok Leyland) was on the main road,doing around 30-40 km/hr.I was standing near the front gate,casually looking towards the driver(in his mid 40's) as he had his left foot resting on the engine cover.I first thought that the bus must be coasting in neutral and that is the reason he does not need the leg on the clutch,but i was in for a surprise when he changed the gear without using the clutch at all.There was no grinding noise etc and the bus shifted perfectly to the next gear.I even asked him,"clutch ke bina kaise change kiya aapne",he replied "clutch nai chahiye hamesha".

I would really appreciate if someone can explain how he managed to pull this off perfectly,is it some kind of technique used in heavy vehicles ?

Thanks in advance.

[binaiks]

Originally Posted by OSH

I would really appreciate if someone can explain how he managed to pull this off perfectly,is it some kind of technique used in heavy vehicles ?

It generally works as long as you do the gear shifts at the correct rpm. It works even in your vehicle (a trial is NOT recommended, obviously).

[OSH]

Originally Posted by binaiks

It generally works as long as you do the gear shifts at the correct rpm. It works even in your vehicle (a trial is NOT recommended, obviously).

Thanks,that means he was perfectly rev-matching ?
Glad to see such techniques being used,I guess it is just another way to not get bored of your job.Hats off !

[binaiks]

Originally Posted by OSH

Thanks,that means he was perfectly rev-matching ?
Glad to see such techniques being used,I guess it is just another way to not get bored of your job.Hats off !

Generally commercial drivers are experts in Rev matching. You would see this happening a lot on State transport buses.

[dreamliner17]

Question: What does BEST do with roughly a couple hundred 'loss making' Cerita AC King Long buses in Mumbai ??


The Cerita King Long in the background

Answer: Spend some more money by painting it red and black, put regular windows and Voila ! You have a 'non ac' Cerita King Long !


Just saw this converted non-ac Cerita King Long Bus outside Churchgate station, today evening. According to newspaper reports, BEST was mulling to convert these buses to non ac and plying them on the fort ferry route in South Mumbai. Will people like me, now want to travel in the Ceritas? Oh yes!

[silversteed]

Originally Posted by dreamliner17

Answer: Spend some more money by painting it red and black, put regular windows and Voila ! You have a 'non ac' Cerita King Long !

The BMTC of Bangalore had a similar species, but from Tata - a low-cost AC bus built on TM's LPO 1618c RE chassis, and fitted with AT. After frequent breakdowns, the corporation decided to scrap all 98 of them. But they did convert a couple of them (or was it only one?) to non-AC and tried that option too.

[blackwasp]

Originally Posted by OSH

I would really appreciate if someone can explain how he managed to pull this off perfectly,is it some kind of technique used in heavy vehicles ?

Generally, the bigger engines in buses, trucks etc have lower engine speeds than our cars. The driver can match speed of the gearbox and drive shaft (synchronise) and once they are at same rpm, gears can be changed without the use of clutch.

Even in our normal cars, you can do this, but there should be no grinding noise. I've tried this a couple of times on our old 1.2 Punto, and I found that I could shift at around 2250 rpm. For downshifts blip the throttle to increase the revs and for up shifts let off the throttle so the revs fall.

This clutch less gear changing is more used by truck drivers/race car drivers because they need to always be in the power band.

[dreamliner17]

Originally Posted by silversteed

After frequent breakdowns, the corporation decided to scrap all 98 of them. But they did convert a couple of them (or was it only one?) to non-AC and tried that option too.

If something like this could happen to TATA buses, i am shocked. Perhaps, the Bus industry isn't quite agile with implementing multiple/rapid technological advancements, in the same go. Say for example Cerita giving you AC + Air Suspension + CNG based engine + AT, in an all-in-one package. I remember my school days (in the 90's) when Power Steering or the Turbo charged engine was made a mandate (and suitably advertised via stickers) in commercial vehicles, and it was brought-in one advancement at-a-time. If my memory holds true,'Automatic' written in yellow paint on the side-body panels (just beside the inlet for the diesel tank), signifying the use of an automatic gearbox, was a feature that existed in the BEST buses even in the 90's. I have no clue how reliable they were at that time.

Enter the Volvo era in buses in India, and all bus manufacturers wanted to make their product a 'Volvo'. But it was much more than simply copy pasting the headlights or tail lights or VOLVO name, on the regular buses. Cerita failed because it genuinely lacked quality in all aspects. If TATA or Ashok Leyland or Eicher would do the same due to 'peer pressure', i would be highly disappointed.

Originally Posted by blackwasp

Even in our normal cars, you can do this, but there should be no grinding noise. I've tried this a couple of times on our old 1.2 Punto, and I found that I could shift at around 2250 rpm. For downshifts blip the throttle to increase the revs and for up shifts let off the throttle so the revs fall.

I try this quite often in my Spark and have been following this technique for quite some time now. It is much easier when you have to downshift (say when you are approaching a red signal and you gradually press the brakes without the clutch and slowly ease-out the gear to neutral). Upshifting without the clutch is much more difficult and requires high precision, or you will be causing much more harm than benefit! The technique is to slowly and gradually apply pressure on the gear lever till it slots-in perfectly. I do not use blipping since majority of the times it leads to an excessive grind. So i avoid it. Does this technique cause any harm? Well..soo far, soo good! Also, i have tried this on the Dzire and have had very less luck. Maybe the newer 'slick' gearboxes do not support this!

Originally Posted by blackwasp

This clutch less gear changing is more used by truck drivers/race car drivers because they need to always be in the power band.

I would think of this to be a very tricky situation. In the higher revs, the gear teeth are firmly locked into place and i do not think that they can be got apart, merely by just pressure on the gear lever (without too much damage)

[OSH]

Originally Posted by blackwasp

Even in our normal cars, you can do this, but there should be no grinding noise.

This clutch less gear changing is more used by truck drivers/race car drivers because they need to always be in the power band.

Thanks for the information.Now even though I know the technique I am scared to perform it on my cars,I rather use the clutch and avoid grinding the gears.

Another thing would be that most commercial drivers do not own the vehicles,so they do not mind using such techniques.Afterall if something goes wrong the owner of the vehicle will pay for the repairs.

Also you mentioned that this technique helps to keep the vehicle in the power band.Leaving racing aside,does the use of clutch while changing gears(matter of a few seconds) in heavy vehicles cause such a significant amount of drop in performance that this technique has to be followed ?

[blackwasp]

Originally Posted by OSH

Also you mentioned that this technique helps to keep the vehicle in the power band.Leaving racing aside,does the use of clutch while changing gears(matter of a few seconds) in heavy vehicles cause such a significant amount of drop in performance that this technique has to be followed ?

Depends. On a steep incline, even a drop of performance will cause rollback of a 15-20 ton vehicle. I really admire truck drivers who are stuck in traffic (in an incline/ ghat) and have 0 roll back when small cars try to cut across them. We must appreciate these truck drivers more.

[OSH]

Originally Posted by blackwasp

We must appreciate these truck drivers more.

Completely agree with you on this point.We are very comfortable in our cars,surrounded with all the creature comforts whereas these drivers have got next to nothing in terms of comfort.Also not to forget the level of stress they go through by driving for long hours without proper halts for rest.

[amtak]

What best needs is not big buses, but smaller Bharat Benz buses in 2 door configuration - Both in AC and non ac type.

Don't really understand the need for a bigger bus now in crowded city like Mumbai.

Thanks!

[Dieseltuned]

Originally Posted by dreamliner17

Question: What does BEST do with roughly a couple hundred 'loss making' Cerita AC King Long buses in Mumbai ??

Will people like me, now want to travel in the Ceritas? Oh yes!

This definetly looks much better then the original Ceritas. Especially the paint scheme. Hope they do this to all the remaining ceritas, atleast that will help them cut losses by running them in their current avatar.

Regards
Dieseltuned

[amtak]

Originally Posted by Dieseltuned

Hope they do this to all the remaining ceritas, atleast that will help them cut losses by running them in their current avatar.

Regards
Dieseltuned

I hope that, they do not do this for the remaining Ceritas. These buses are expensive to maintain and running them in the fleet will not be a good idea. High time that they are discarded (I stopped sitting in them in 2011!).

Take a cue from smaller corporations, to buy either MarcoPolo or Eicher buses and run them till they can buy Volvos.

[OSH]

Originally Posted by amtak

Take a cue from smaller corporations, to buy either MarcoPolo or Eicher buses and run them till they can buy Volvos.

IIRC there are a few AC Volvo's that are running on the worli route. These have started to show-up only a few months back but they look like they have been bought second hand from somewhere. Are they on test ?