1982 XJ650 Maxim - Tach Gauge/Cable Question

I have a new to me 1982 XJ650 Maxim that I'm slowing bringing back to life. When I pulled the gauges off, I noticed it does not have a power supply going to the tach gauge even though there is a hole in the back of the gauge for it. Also, there was no tach cable on the bike when I got it. I was planning on getting a cable anyway and that's no big deal, but I can't even find on the motor (front or otherwise) a place for the tach cable to go. Anybody got any ideas on that? I just think it's strange that I'm missing a power supply to the gauge, there is no cable and I can't find anywhere to put one on the motor if I had one.

-Chuck

 

Your bike has an electronich tach. I believe it should have two pigtails hanigng from it: On has black and green wires for the light. The other has brown and red for the tach itself.

I think the pigtails connect to the harness inside the headlamp.

 

Where does your tach cable connect to your motor on the 1982 XJ650 Maxim?

 

not sure about the 650, but on my 550, the tach cable connects to the cam housing just above two of the exhaust manifold pipes.

 

Yours is a mechanical tach. The OP's bike is electric, and doesn't have the tach output drive and cable that yours does.

 

I have an 83 650 seca with 82 650 maxim engine in it and had to convert the gauge cluster to the eletric tach. You will first need a gauge set with a etetric tach. If you dont have the wiring for it thats ok. There are three wires to make the tach work. (Black-ground) (Brown-12+Volts) (Orange-run a wire to the orange wire on the coil) Hope it helps.

 

I wish mine was electric...the cable leaks oil a bit where it connects to the engine.

 

Your tach-drive seal is toast, or has simply become fossilized from age. The dealer has them, they don't cost much, and they're pretty easy to install. It won't completely cure the leak, but it will help.

 

Mine appears to be an electrical tach since there is no motor connection apparent on the front top of the engine. So I'm guessing someone had already replaced the speedo/tach before I got it? Doesn't make sense that the tach has a hole in the back of the gauge for wires that are missing and also a cable connection on the bottom of the tach if it should be an electrical system, does it? Those electrical gauges must be scarce because I've seen lots of the cabled ones for sale, but none that do not have a cable connection on the bottom of the tach.

 

Sounds like a previous owner might have bought a pre '82 gauge set (or possibly a set for another XJ model) without realizing that there were both electrical and mechanical tachs that looked very similar.

I believe you'd need a new head and exhaust cam to convert the engine - much easier to put the proper tach on. They show up frequently on eBay.

Might be interesting to look inside the headlamp housing and see if the connectors for the tach are there.

 

I do have the headlight taken apart right now and there are a few plugs that were not being used so one is probably for the tach. How does the electric tach work? I wouldn't think the plug from inside the headlight is going to get the rpm's from the engine so is there another attachment that goes somewhere on another part?

 

Well actually, everything that is electrical on the handle bars goes through the headlight housing...so the tach connection is probably in there as well.

 

I'll get skewered for my oversimplified answer:

Mechanical tach counts revolutions on the drive cable (just like your speedometer).

Electronic tach counts electrical pulses to the coil. The orange lead on the tach plug goes right to the primary on one of the coils.

 

Here ya go.

eBay

 

I'll get skewered for my oversimplified answer:

Mechanical tach counts revolutions on the drive cable (just like your speedometer).

Electronic tach counts electrical pulses to the coil. The orange lead on the tach plug goes right to the primary on one of the coils.[/quote]

I'm not real stupid, but that's what I wanted to know. Thanks.

 

I saw that one. I just emailed him to see if there is a cabled connection on the back of the tach (which I don't want). If not, I'm assuming that one is the type I need. Thanks.

 

I pulled my gauges off tonight. There is a pigtail coming off the tachometer that carries all four wires and terminates in a single connector (not two as the wiring diagram I have seems to indicate). That connector plugs into the harness inside the headlamp housing.

Photos:

 

Hey guys, I know its a super old thread but is still the closest to my current dilemma. I'm a total noob at this and have searched all over the internet & read countless forums. But can't seem to find what I need. I purchased the mini speedo & tach from DimeCity to replace OEM gauges.
Bike is 82 XJ650 Maxim
The Problem: I can't figure out how to wire up the tach - since it only has 2 wires (Red & black - which already have connected for backlight). So now I'm left with Tan & Orange cables from bike. ¯\_(ツ)_/¯
The aftermarket tach from DimeCity(1:5 ratio):


1. Seems to me that the tach is not the electric kind (I could be wrong)
2. Can't seem to find any other of this same look/design(2.5 mini tach) to only have wires with 1:5 ratio for the bike

ANY HELP with this will be much appreciated!!

 

@Via The 82 650 Maxim has an electronic tach, that one is mechanical (uses a cable) and is not compatible with your engine. Go shopping.

 

That's what I was afraid of... sighhh -Do you have any recommendations on where to find one?

 

Have done many searches to no avail

 

The XJs use a wasted spark system so it will provide more 'signals' then an aftermarket tach is expecting. You will need a tach that supports a 2 stroke engine so it will read the correct RPM. Some TACHS come with a 2 stroke\4 stroke switch.

 

Thank you for the reply!

 

Jpcycles.com appears to be a popular online store and has many options that should work for you.