Minecart(or minecart with chest) bug

hmm,looks minecart doesn`t move.
and can be listen sound.
(Minecraft 1.11.2 2017_01_06 11_38_56.mp4)

Steps to Reproduce:
1.put MANY minecart(or with chest) on the powered rail.
2.place some rail(normal) to around(Like 2017-01-06_11.51.50.png)
3.send redstone signal to powered rail
4.DONE.
*careful,if restarted minecraft,this bug is repaired.)

sorry,I`m not good at English.