Need speedo wiring help

[jmnjrpa]

Just replaced a busted 160 speedo with another (good hopefully) that has identical face with no extra/missing lights, etc. Went to plug it up and found it had a 4 prong plug whereas the old one had a three. All colors are the same except it has an additional black with white stripe. Any info would be appreciated. Thanks







All pics have the old unit on the right side of pic.

[crazy steve]

John, that 'extra' wire is just the ground return for the turn canceller reed switch. Should be the same as the plain black wire in your existing harness, and is tied internally on the later bikes; this appears to be a '79SF speedo.

'78E original owner

[jmnjrpa]

Thanks Steve,

I suspected that might be the issue. Just could not understand why the previous one had 3 wires as 79 was the last year of the 160 speedo. They might have changed in the middle of the year.

[crazy steve]

Or maybe someone swapped the speedo harness; I don't have one if front of me, but aren't those reed switches removable? If so, you should be able to swap the 3-wire for the 4-wire and not have to change/splice anything.

'78E original owner