Klankety, Klank!?!

lemme guess you're bike sounded like this...



my bike back before i synch the carbs and cleaned the tank with BB's and chem-tool.

lots of soot and #3 and #4 -- would check floatbowl fuel level using clear plastic tube test.

cranked the air screws out an extra turn from normal (now at 2 1/4 turns) . . . cant tell by ear (or tach) if the rpm is rising or falling when I'm individually tuning each carb air screw -- likely something wrong in the pilot circuits.

Should first assure all other tuning components being up to specs (ignition, new plugs, correct valve clearances, ample clean fuel supply, etc.) before addressing carbs. Because even perfect carbs rely on and can't compensate for defects in other components.

Carbs should be in otherwise perfect as-new condition before synching and lastly adjusting the pilot screws.

Good Luck!

Your starter clutch bolts are loose/broken. Pull your stator cover and look. You should not be able to move the starter clutch, which is behind, bolted to, the rotor. If you can move it, you need to pull the rotor and replace, and locktite, the bolts. While you have it apart, it is a good idea to replace the rollers and springs too. Z1 has the parts and tool you will need.....chris3

All incredibly valuable information! Thanks sooooo much! I will let you guys know how it goes, as soon as I get some free time this coming week to work on it. Just one more question - If I'm getting 140psi right across all four cold, do i really need to check the valve clearances? Maybe bring it to temp and then check compression?

Cheers!

PS. Makarth, mine isnt quite that bad(loud). But sounds very similar.

TeK9iNe wrote:

...If I'm getting 140psi right across all four cold, do i really need to check the valve clearances? Maybe bring it to temp and then check compression?...

As known, because of metal expansion when heated, cold valve clearances diminish at normal operating temperature. The factory specified gaps when cold are calibrated to allow for the expansion when heated, to assure the valves being allowed to fully close (and thereby properly seat and seal) at normal operating temperature.

If some minimal below spec gap exits when cold, the valve may be seating well enough to allow full compression when tested, but the clearance may disappear at normal operating temperature.

Good compression test figures (even on a "warm" engine) do not guarantee proper valve clearances. Although the odds in favor of having decent valve clearances are logically better while compression testing at the hottest feasible engine temperature, the actual clearances remain unknown without actually measuring them on a cold engine.

With continuing engine operation, the valve clearances gradually and naturally diminish. Absent routine inspection and adjustment, when a valve with insufficient clearance first starts leaking, the loss in engine performance may be recognized in time to take corrective measures before the valve and/or valve-seat is damaged (burned). But why risk such damage? Especially when checking valve clearances is so quick and easy, and essential to optimum engine performance (not to mention being specified by Ma Kaw as a required routine maintenance item).

And besides, on an engine with a leaking valve, it's virtually impossible to correctly adjust even perfect as-new carbs. And this obtains regardless of acceptable compression test figures. The bottom line is that going to the trouble of synching and adjusting carbs without first assuring proper valve clearances may be a waste of time. Same as doing so without first assuring that all the other non-carb components are also up to snuff.

Even perfect as-new carbs cannot compensate for a defect in another component. That's why the shop manuals specify carb adjustments as the final item in tune-up procedures.

Reminder -- as noted by coppertales and in other posts, would pull the stator cover and inspect for loose or broken starter clutch bolts. Recall, the noise is coming right from the stator/just behind that area.

Don't mean to sound preachy . If so, please forgive that. :blush:

Good Luck!

OK! Checked the valve clearances... everything was ok. Worn just a small bit, but OK. The last guy said he looked at them...

So i finally replaced the starter clutch bolts (that were so loose i backed them all out by hand once I had the stator off)! Things were pretty chewed up... replaced the pins and springs in the starter clutch. Cleaned and sanded down all the scored surfaces (from the loose bolts). Lubed and reasembled (properly tourqued)everything with a new gasket... and YES! She cranks over and purrs like a kitten!

NO MORE KLANKETY!

Sounds great, and runs even better... now that I got a mannometer, and tuned up the air screws right.

Hooray!

Thanks to all, for the help and advice!

Cheers!

Hey,
Couldn't help but read all of your posts. I been restoring my 81 kz750 for two years. I have been riding it for a few months now, and my starter clutch seems to not be working as good as before. At about 1000 rpm's I get some noise. I've been pop the clutch in second gear to start mine initially, but once heated she seems to start fine. Of course if the bike cools off, Back to popping the clutch. Anyway, I've been debating either fixing, or selling the bike. I don't find myself having alot of time to monkey with the bike. Four kids, a wife, band, and job. Was wondering how long it took to repair the starter clutch issue, and was it expensive. Did the motor have to come out of the bike. Any info would be appreciated. I love the bike, but I don't want to push it just to ride it.

thank's John

Hey,
Couldn't help but read all of your posts. I been restoring my 81 kz750 for two years. I have been riding it for a few months now, and my starter clutch seems to not be working as good as before. At about 1000 rpm's I get some noise. I've been pop the clutch in second gear to start mine initially, but once heated she seems to start fine. Of course if the bike cools off, Back to popping the clutch. Anyway, I've been debating either fixing, or selling the bike. I don't find myself having alot of time to monkey with the bike. Four kids, a wife, band, and job. Was wondering how long it took to repair the starter clutch issue, and was it expensive. Did the motor have to come out of the bike. Any info would be appreciated. I love the bike, but I don't want to push it just to ride it.

thank's John

Starting a new thread about your problem would be a good idea

The 750 and the 1000's are different beasts, the starter clutch on the 1000 is under the left side engine cover, while the starter clutch on the 750 four is inside the engine case on a secondary shaft.

There is an article on repairing the starter clutch on a 650 (same design as the 750 four) in the Filebase under the KZ Information tab at the top of the page here. That article will tell you everything you need to know to accomplish the job.

I went ahead and looked for the article, here's a Link to it

Its really not difficult at all... but you may have to search around for parts. And you deffinately have to order a special too from Z1 Enterprizes (a puller) to get the stator off.

The engine doesnt have to be removed from the bike at all, just one side cover, and thats it.

It can take a while to get parts, once you have determined which ones you need. But, they arent really expensive.

If time is a constraint, a shop usually can do it in about 2 hours, but parts can take a week or more to come.

Guess its up to you...

Cheers!

BLAH, I didnt even see what bike ya had! Sorry, see post above :S

I am trying to pull my flywheel on my 78 kz750. I am trying to find the tools to perform the task. I found a site that sells the flywheel holder and puller. Together both would be about $300.00. Does anyone know an aftermarket alternate for these. I know several of the web sites sell them. Not sure which one will work. Any info. would be helpful. I am
trying to pull the flywheel so I can get to the starter clutch. The sprocket is loose and the 3 bolts that are bolted on from the inside of the flywheel are loose as well.

Thanks, Randy