Upgrade to Electrical Tachometer on a 550 Maxim?

Hello XJ Masters! My '83 550 Maxim has the mechanical tachometer, but the needle inside is busted off so i can't see my rpm's. I went and got a gauge cluster off of a 650 maxim which has the electrical tachometer. Is there any way to get the new set to work on my bike?

 

You need to get your hands on a wiring diagram for the bike the cluster is from; I believe the electronic tach takes its pickup off one of the ignition triggers.

You could also find a good used 550 cluster on eBay and play mix-n-match. They come apart.

 

You sure can. Capping off the old mechanical drive will be the hard part.

On the Tachometer electrical connections:

Tan wire - goes to switched hot. On the 650 it connects to the hot side of the neutral light (also tan).

Black wire - ground

Orange wire - to TCI-coil lead. On the 650 that wire is also orange. There are 2 wires to each coil. One of the wires on each coil will be the same color (probably red with white stripe). Connect the orange wire to either mis-matched coil wire.

The blue wire goes to the instrument light positive.

 

Re: Capping off the mechanical drive: Get ahold of an old tach cable and "liberate" the threaded collar. Scrounge or cut a circle of anything stiff that will fit inside it; coat one side with gasket sealer and screw the cap with the gasket-cement coated disc in it back on. Capped, and reversable if ever you want.

 

Brass shim stock should do the trick and it is easy to work with.

 

I wonder if a DIME will fit? I'm interested in this too, because the only tachs that match the 150mph speedo I fitted are electronic. Plus getting the tach cable out of the way will help in fitting the FJ600 oil cooler I picked up.

 

Thanks! I'll get out to the garage when it warms up a bit more. I think it got up to 16 degrees fahrenheit today!
I'm sure I'll have more questions later...electrical is not my favorite system to mess with...