प्रयागराज एक्सप्रेस - जो भी हो तुम खुदा की कसम; लाजवाब हो

CBC's give a lot of jerks compared to screw couplings. Even with LHB coaches, many times we can feel jerks when the train is starting. This cannot be completely avoided, but can be greatly improved.
ICF CBC coaches were going fine, but there were 2 problems. The first set of coaches had very strong jerks. Then they abandoned the experiment and moved to H-LHB coaches. Later on that was also abandoned to concentrate on LHB coaches. ICF was unsuccessful in their first attempt at adapting CBC for ICF coaches. It could have been done if followed up properly, but the experiment was abandoned in between.
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Another reason was the WAP7 locomotive. The extremely high starting acceleration for the WAP7 is particularly bad for CBC couplings as they can break if not properly buffered. LHB coaches have better CBC couplers and the coaches are also lighter than ICF coaches. So, P7 was not bad for them. But for the regular LHB rakes, P7 links can result in more coupler maintenance.