Mysterious wire

After going out laning on Sunday I noticed a heavy duty cable hanging down on the nearside under the battery compartment. The other end was connected to the end if the starter motor and the loose end looks like it had a battery terminal connector on it.

No-one I was with had any idea why the cable was there.

anybody have any idea ?

I have removed it and havent noticed anything different (besides my starting problems but I don think it's related)

Cheers

Earth wire perhaps, hence the starting problems. Model etc?

2.5 na 1986 90

After removing the wire it did start straight away though. I checked the battery compartment tonight and cant see any obvious place that it would have been connected.

Anyone else with a 2.5na 90 have thus wire connected ?

Cheers