speedo change

[oldyam80sg]

I changed the speedo that was on my 80 SG to a speedo that came off a 79 SF.I thought it was a plug and play thing but it turns out it really was not.On my SG there is a 3 pin connector and on the SF there is a 4 pin connector.Had to disassemble the speedo and found out my SG's speedo had some rust on the inside of the housing.After looking at both parts- i just changed the wiring harness from the SF speedo and put my SG harness on instead.Put everything together and took bike for a test ride.Works perfect!

[bikerphil]

Glad it worked out for you. Plug it in to find out it don't work and you'll have to play with the wiring to fix it.

[b.walker5]

Without looking at the wiring diagrams I,m pretty sure the difference in plug is due to the SG having a common earth pin for the idiot light and the self canceller reed (wires are joined inside black sheath at some point) and the SF having a seperate earth for each item. If need be you could simply cut the plug off the SF unit, connect the earths (black wires) together and join the wires to your existing SG plug.

[tw1980]

Sorry

Sorry about the bad advise I could have sworn mine just plugged in when I changed over. Terry

[oldyam80sg]

Aah-nothing is plug and play-except for Geezers rectifier/regulator unit.No biggie changing the wires from the SG.i have taken the speedo apart many times,just have to be sure you don't pinch the reed wires and that the bulbs go into their holes.