[Reinhard]

Posting to an old topic- but I think makers like WABCO etc. should try (they must be obviously already trying) and deliver good AMTs for passenger cars. With alternative suppliers, the current monopoly of Magnetti Marelli (FIAT owned) will diminish & we'll have a healthy competition. Its beyond doubt that the technology is well accepted in our car segments so the investment certainly will bring returns.

[Motard_Blr]

I rode on a Indigo airport bus yesterday at BLR and I noticed the Wabco AMT on the AL bus. I was observing the gear shifts as we were moving and noticed that upshifts were quite smooth but downshifts, not as much. The problem was that the AMT automatically shifts down as the speed decreases and releases the clutch a bit too fast, causing a jerk when the engine engages.

I think that this sort of jerking motion is bearable for sitting passengers but difficult for standing passengers. City buses with AMT are some way away...

[Anwesh]

Originally Posted by Motard_Blr

City buses with AMT are some way away...

Well, AL JANBUS with AMT are already running for the past few months with Solapur and Kalyan Dombivli Municipal Transports.

Regards,

[silversteed]

Originally Posted by Motard_Blr

City buses with AMT are some way away...

Originally Posted by Anwesh

Well, AL JANBUS with AMT are already running for the past few months with Solapur and Kalyan Dombivli Municipal Transports.

Add to that, CSTC of WB, JCTSL of Rajasthan, HRTC of Himachal Pradesh, APSRTC.

Even before the launch of JanBus, AL had started offering AMT in their intercity coaches - VRL and KPN have quite a few such buses in regular operation

[Anwesh]

Originally Posted by silversteed

AL had started offering AMT in their intercity coaches - VRL and KPN have quite a few such buses in regular operation

Are these 12Mre (3/33) chassis with 225BHP CRC engine? Would like to get some reports on these buses.

Regards,

[Mpower]

Originally Posted by Nitronium

Feel free to ask about the AMT system. I shall do my best to answer any queries

Thanks for the writeup

Any idea what is the shift time in milliseconds?

[Ashley2]

Originally Posted by Anwesh

Are these 12Mre (3/33) chassis with 225BHP CRC engine? Would like to get some reports on these buses.

Regards,

The 12M RE chassis are with 225HP CRS engine. There are quite few buses running for the more than 3 years with Sharma, NAS, Vivegam etc. SRM, SBLT, APR are new with a newer ones and they are almost year old.
This chassis comes with 225hp CRS engine, 6 speed Leymatic AMT, Telma retarder, tubeless radials, full air suspension.
This is the only RE Chassis available in India currently and seems to have managed to come out with a perception that only Volvo can make RE Buses. Isuzu failed in a big way, Corona didn't find any takers in private, Tata nothing to speak on.

[Anwesh]

Originally Posted by Ashley2

The 12M RE chassis are with 225HP CRS engine. There are quite few buses running for the more than 3 years with Sharma, NAS, Vivegam etc. SRM, SBLT, APR are new with a newer ones and they are almost year old.
This chassis comes with 225hp CRS engine, 6 speed Leymatic AMT, Telma retarder, tubeless radials, full air suspension.
This is the only RE Chassis available in India currently and seems to have managed to come out with a perception that only Volvo can make RE Buses. Isuzu failed in a big way, Corona didn't find any takers in private, Tata nothing to speak on.

Am aware that the 12Mre is with 225 CRS engine, my question was whether the buses with VRL and KPN are with these engines or the older J series. The Sharma bus that comes to Mumbai is the older J series one with manual transmission. I have inspected the new chassis at AL RSO Talegaon and am looking for a comprehensive hands on report from an actual user/operator. Not a single one is with a Mumbai or Maharashtra operator so far.

Regarding Corona, a section of Mumbai and Pune based operators was very much interested but the company does not seem to want private sector business.

Regards,

[binaiks]

Originally Posted by Anwesh

Am aware that the 12Mre is with 225 CRS engine, my question was whether the buses with VRL and KPN are with these engines or the older J series. The Sharma bus that comes to Mumbai is the older J series one with manual transmission. I have inspected the new chassis at AL RSO Talegaon and am looking for a comprehensive hands on report from an actual user/operator. Not a single one is with a Mumbai or Maharashtra operator so far.

VRL and KPN aren't operating the 12M RE version AFAIK - both of them operate the FE 12M version. The older Sharma bus is not a J Series as well - its a H series 12M RE version which came initially with manual transmission.

[silversteed]

Originally Posted by Anwesh

my question was whether the buses with VRL and KPN are with these engines or the older J series. The Sharma bus that comes to Mumbai is the older J series one with manual transmission.

AFAIK, the only known operator running a J-series engined AL is APSRTC - they have a few Luxura coaches from the first lot, which used to be seen on some Bangalore bound routes.

[Viju]

Originally Posted by Ashley2

Also now GoI is mandating AMT or AT fir city buses produced post April 2015 when purchased under JNnurm.

Very happy to know that even GoI is pushing for auto transmissions for city buses. They should be much more comfortable for the passengers as well as the driver.

But usually, regulations are born out of concerns of safety or emissions. In this case, what was the background for GoI mandating A/T for city buses? Pardon my total ignorance about CVs. Curious to know.

[ajman28]

Originally Posted by Mpower

Thanks for the writeup

Any idea what is the shift time in milliseconds?

The shift times for a CV AMT can vary anywhere between 500 ms to 1500 ms.

The up-shifts usually happen quickly whereas the down-shifts might take some more time. Too many factors come into play for deciding the shift timings hence it is difficult to mention one single number

[Ashley2]

Originally Posted by Viju

Very happy to know that even GoI is pushing for auto transmissions for city buses. They should be much more comfortable for the passengers as well as the driver.

But usually, regulations are born out of concerns of safety or emissions. In this case, what was the background for GoI mandating A/T for city buses? Pardon my total ignorance about CVs. Curious to know.

Here this was driven b MoUD under Urban Bus Specification. This was purely without any background and just to give a better transport for public.
UBS itself is a huge milestone in Indian bus Industry otherwise we will still be running with regular floor buses.
This has fast forwarded Indian bus industry by atleast 10 years.

[kat]

Originally Posted by ajman28

The shift times for a CV AMT can vary anywhere between 500 ms to 1500
ms.
1
The up-shifts usually happen quickly whereas the down-shifts might take some more time. Too many factors come into play for deciding the shift timings hence it is difficult to mention one single number

Having worked in the AMT software earlier (with Wabco), the best shift time that we have observed has been closed to 40 ms (usually during an up-shift from 4-5 or 5-6 where no speed matching is necessary) and worst shift time has been close to 2-3 seconds (when a gear during downshift does not slot properly and a re-shift occurs).