This is off-topic for this thread but C Stock had ’72 Stock has a very fierce transition from electro-pneumatic to rheostatic braking and back again.
With electro-pneumatic initially applying on all cars, above 15mph and below 40mph, then dropping off on motor cars when the rheostatic brake proving circuit was made.
This caused a significant lurch in braking which was out of the drivers control.
When speed was reduced to below 6mph the rheostatic brake now dropped off, there being insufficient energy to produce the brake force, the electro-pneumatic would now apply on the motor cars, causing yet another uncomfortable lurch.
Upon refurbishment some of issues were addressed, C Stock motors were tweaked slightly to improve the transition
I’ve also heard it suggested that the Northern Line 72 stock was somewhat left to rot during the 1990s, which further exacerbated these issues.
Certainly there’s plenty of stories of trains which would behave perfectly well for most of the journey, then the driver would suddenly find themselves shooting past a stopping mark.
The same seems to have applied to the 59 stock in terms of being in a poor state, however the general view was that a 59 stock might be a good or bad train, but would be consistently one or the other. Whereas a 72 stock could be very variable from one minute to the next.
The current Bakerloo fleet doesn’t seem to be berated in quite the same way, so evidently things have been done to them over the years that have improved their handling.
Correct me if I'm wrong, but I believe you can tell which were the ex Northern Line vehicles by the black and white spot / triangles on the wall panels at the facing seats too. The native Bakerloo one's are brown and white.
To some extent yes, however the first of the four trains was moved to the Bakerloo before being refurbished, therefore doesn’t have these features. Also one of the units contains two 72mk2 cars.
There are some other giveaways. All the doors were replaced some years ago, so look completely different to the native fleet. At least some of the M doors retained the plated-over aperture for the train set number, which the MK2 fleet never had - I presume this is still the case.
These four trains really are quite lucky to have outlived the rest of the fleet by just 25 years and counting!