Even though the LHB coaches are fit to travel at 160kmph, It is not desirable to permit non-air conditioned coaches for speeds more than 120 kmph
due to dust ingress and air blast. (Source - RDSO report on running high speed trains in NDLS-BCT and NDLS-HWH routes. Link below). Because of this, even if trains get LHB coaches, they won't go beyond 110- 120 kmph if they have non-A/C coaches.
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