Tach Doesn't Work

Hey folks,

Everything on my new (to me) '81 KZ550LTD works except the tach. Seems to be a mechanical unit with a cable that inserts into a hole in the cam cover. When I bought the bike, it was disconnected. I reconnected it but it still doesn't work.

Anyone have any insights? My Clymer manual doesn't cover this.

Dago Trojan
Aquasco, MD
81 KZ550LTD
04 Honda CRF230
73 Hodaka "Dirt Squirt" (Project)

Ah. Common enough issue.

First question that needs be asked - did that disconnected tach cable come with a core? It's somewhat a necessity to ask, as there's a surprizing number of people that'd miss a minor detail such as that.

If it does, screw the cable into the fitting on the tach - making sure the core seats in the tach drive hub - take the other end and give it a clockwise spin with your fingers. If the tach needle bounces, chances are the tach works, though whether it works accurately is another issue.

If the cable has a core and the tach works, then it looks like you're in for a voyage under the cam cover. Not sure about how the KZ550 is set up, but it's possible that the tach drive gear under the cover is lunched - if I recall correctly, some of those drive setups were of the hard plastic variety, and could have shattered, or just plain wore out.

Post edited by: Pterosaur, at: 2006/12/15 16:40

funny i'm just in the middle of this myself.

maybe you've just got a bad connection or bad tach drive gear.

but if the tach is broken, you might want to consider just swapping in these gauges:
tinyurl.com/w49vo

they're from a 1982 550 ltd. i checked kawasaki.com and the 1982 tach is not exactly the same part number as the 1981, but if you're swapping the entire instrument panel, might not make a difference.

i've got a canadian 1980 kz550 and i gave up looking for a replacement tach. it's easy to find replacment gauges on ebay, but the USA models have beige needles and the cdn models have white needles.

yesterday i started taking the tach apart to fix it, using these directions, and it's a lot easier than i thought it would be (honda pics):

www.cb750cafe.com/parts.php?id=5&PHPSESS...b2b8523e8089011a564b

the inside of a KZ tach looks pretty much the same:
www.z1enterprises.com/reference/ZResto_inspection.aspx

the trickiest part is taking off the (press-fit) needle, but it finally came off. i'm going swap in the inside guts from one of the USA models i bought off ebay.

hopefully you've just got a poor connection/bad tach drive gear, and can save yourself this hassle. good luck.

Does that Z-Resto place do gauges from all KZ models? And what do they charge I wonder?

del

pumps wrote:

Does that Z-Resto place do gauges from all KZ models? And what do they charge I wonder?

i sent my kz550 tach to him three weeks ago to be restored, but he returned it cause he only does z1/kz1000/650 gauges. the price is about $100, give or take.

given the fact that i had emailed him in advance, let's just say i was a bit surprised. :huh:

Well I have a 650 so if I need it...I wonder why they don't do 550s?

It is very unlikely that the worm gear on the exhaust cam is broken. That leaves 3 possibilities...
1. cable
2. tach
3. tach drive

1. First, start with the tach drive. This is a bevel gear that engages with the exhaust cam. Take it out and inspect it. It should be retained by a single 6mm bolt or screw in some fashion. Once you remove the bolt or screw, there is a body that is press fit in the cylinder head that the gear fits inside. Remove it and inspect the teeth on this gear. It would be a great time to replace the oring and oil seal. I think www.z1enterprises.com would be a good place to source the replacements. If this gear is OK, then it is the tach or cable.

2. The cable is a sheathe with an actual cable running through the inside. Pull it out and inspect it to ensure it isn't frayed. If you want, wipe it with solvent and re-lube it with cable lube. Put it in the sheathe with the end that goes in the tach installed. Put the other end (normally would go in the cylinder head) in a drill chuck and tighten it up. Put the drill in reverse and slowly increase the speed of the drill and see how the tach reacts. Since you have already checked the cable visually, if the tach doesn't work at this point, the tach is broken. If nothing happens, there are usually few causes except for the spring loaded center pivot arm or pointer arrow being broken. don't know if you could fix these as the spring loaded pivot is magnetic.

Pterosaur wrote:

take the other end and give it a clockwise spin with your fingers.

COUNTER clockwise,You mean.

(Silly):laugh:

Sandy wrote:

Pterosaur wrote:

take the other end and give it a clockwise spin with your fingers.

COUNTER clockwise,You mean.

(Silly):laugh:

:blink: Hmmm. Must've been thinking about the *Down Under Tachs. Yeah. That's it! :whistle:

DOH!!! NOT THAT RIGHT! YOUR OTHER RIGHT, DUMMY! NERSE! :pinch:

Good SAVE!!:laugh: