RPM Gauge

My RPM Gauge is very eratic, it jumps all around and is very bouncy, sometimes it dont even move, what can i do to fix it.

81 maxim 550.

 

'81 should be a manual Tach right, have you tried lubing the cable? Should be pretty easy to loosen and get some *insert preferred lubricant name here* down there.

 

Remove the tach cable; pull the inner cable out and lay it on some paper towels.

Flush the outer sheath out thoroughly with aerosol "brake and contact cleaner" (Brakleen) from the auto parts. Inspect for worn-thru spots or other compromises to the outer sheath. I used to use heat-shrink or paint liquid electrical tape on sheathing breaches, now I just replace the cable.

Clean the inner cable. Inspect for fraying, wear or general unhappiness.

If inner cable happy, proceed. If inner cable bad news, order new cable and then LUBE IT, as follows.

Hang the outer cable up, and use a small funnel or make a paper funnel and pour some motor oil (yes motor oil) down the sheath until it dribbles vigorously out the other end.

Slather the inner cable with oil and reinsert, spinning it with your fingers as you go. Oil will go everywhere, use lots of rags or shop towels. Be sure to soak up any excess before reattaching the cable.

Apply some good high-temp grease (I use moly brake caliper lube) to the bottom 2"-3" or so of the cable, where it goes through the metal ferrule, and a dab on the little bushing on the end of the inner cable, and button 'er up.

It's going to seep some oil the first couple times you warm the engine up but be OK after that, just wipe it off.

THAT WAS THE CABLE.

Now as to the instrument itself, they also get gummy with age and benefit from a good cleaning and lube. Luckily, on your bike the design of the instrument cluster provides for easy access to the instruments themselves.

Cluster teardown (very similar to yours but with fewer wires) http://xjbikes.com/Forums/viewtopic/t=14948.html

Instrument dissection: http://xjbikes.com/Forums/viewtopic/t=15303.html

Have fun with that.

 

ROFLMAO. I'm sorry just can't help myself but A manual tach? I just imagined myself cranking it by hand while doing 120km/h. Me kinda strunk atm. 8)

 

LMFAO @ "Manual Tach"

 

Anybody else?

 

Oh geez lol but yeah, both gauge faces split across the middle , i guess from the bike vibrations, age, i dont know. time for new gauges, Its the part inside that split, not the glass top cover. where the numbers are.

 

Your cluster comes completely apart.

Pick up another cluster off eBay, tear that one down too, and play mixy-match to get a good one.

 

Thanks BigFitz. Your info is great.

 

1980 Yamaha maxim xj650G with 10K miles. I have a squeek,rubbing noise comming from speedometer. Tried grease in cable then onhooked speedometer and sound went away. sound is comming from inside speedometer. How can you get grease or oil inside gauges to quuiten squeek? speed indicater still works fine, no jerking ect.
tks Bill :?:

 

Got to take it apart and clean and grease it.

 

Thanks

Are the gears exposed once inside? and just regular grease? :?:

 

Use a light weight grease, instrument grade is best of course.

 

Scroll up.

Have a look.

 

mine was jumpy, I cleaned it up, but it wound up breaking at the tip awhile after reinstallation. Just too worn down. Some rust got in there as well.
I've got a new one on the way, I hope it fixes the issue.