Fuses in non-TnA engines?

[Super]

I didn't know about these until Mr Ripley and PGMike had talked about them in the TnA engines. I think that these fuse type wires were supposed to protect small circuit boards but I could be wrong about that. But if what you have pictures are from engines without any circuit boards I wouldn't think that the motors needed to be saved from a spike from a 1.5 volt 'C' battery.

I think PGMike had a video about him explaining and replacing one of these I will find it.

Ah, here it is...