Rajdhani is known for it speed and comparison of the speeds of 5 trains is:
(1) 22109-76kmph Runs like Raj on most of section, fastest train on route
(2) 12429-62kmph Convenient overnight train, not the fastest on route
(3) 22411-56kmph, Runs like Raj on NDLS-CNB section only, Rest route is a mix of single & double line
(4)...
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12493-62kmph, Much slower than Duronto (75kmph avg speed)
(5) 22903-66 kmph Runs like Raj on BDTS-ADI and fastest train on ADI-Bhuj
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No.1 train is 22109 LTT-NZM AC express, a full length train with 20 LHB coaches is a class apart, as compared to other options options. Its avg speed (76kmph) is higher than many Rajs.
No.2 train is 22903 BDTS-Bhuj with 66kmph avg speed is impressive, but it has ICF coaches and the no. of coaches is just 16 inspite of the fact that the train is well patronised, the coaches should be increased.
No.3 train is LKO-NDLS - Very good train but with speed slower than expected. After completion of the doubling, it was expected that the running time shall be reduced substantially. Since the route is fully doubled, the journey time for 490 km journey should be between 7 to 7.5 hrs instead of 8 hrs at present.