1980 KZ440 project build...err... rebuild...

I had a thread in electrical on starter removal. As I continued, I noticed there were more things that needed work, and turned it into a project thread.

Here is where I am currently at:

Got it home, swapped the battery.
Checked lights. Everything good (quick test on wiring.)
next, examine the air filter. I find a mouse nest, complete with a piece of rat poison... Not a good find, however, no penetration into the air filter, they just used the box...
Clear rat nest, and attempt to start so I can hear what is going on.


Here is what I hear: poor attempt to turn over, then click click click. I listen to the click to see it is at the starter solenoid, then try again, and here it at the starter as well. Good sign, in a way. To me, the untrained bike guy, it appears that those are good and well. now to remove the side cover (starter cover removed to view starter.)

Another issue... gas leaking both from the right side carburetor and the little "overflow" hose...
~ Upon disassembly of the carburetors, I notice a screw is missing from the float bowl. This screw has been broken off... nice present.
Clearly, at least it appears so to me, it is time to rebuild some carbs.

The bowl that is missing the screws appear to have new jets in it. I am currently working on either getting the old screw out or tapping for another screw. either way, that is fine.

The side cover, however, is being a slight pain. all screws but one broke loose... the one stripped its phillips head... More to follow.

There are no Phillips heads screws on any KZ model; that's why the cross head screw stripped. The writeup below has a section that explains the problem.

Many newbies and not so newbies run into or issues with their bikes which could be easily avoided with a little preparation or information. Here are a couple recommendations that I hope you will find useful.

Before riding your KZ you should take a little time to become familiar with it. Simple things like checking the oil, tire pressures, etc. are explained in the Kawasaki Owner's Manual. If you bike didn't come with one (they normally are in a little holder on the bottom of the seat) you can usually find one on eBay - be sure to get one for your exact year/model.


MANUAL

You really should consider buying the Kawasaki Factory Service Manual for your bike. The factory service manual provides instructions on the various maintenance procedures and schedules for your bike, procedures for diagnosing problems, proper torque values for the various fasteners (VERY IMPORTANT), and insight into how each system on your bike works even if you are not repairing that system. Studying the manual before you attempt performing service on your bike will impart an understanding of the system you are working on which will increase the odds of success.

The manuals usually are readily available for most models on eBay and other sources; but be sure to get one that has your specific year and model in it as there are differences between the various KZ650 models. I do not recommend Clymers, Haynes, or other aftermarket manuals as I have seen instances where they provide inaccurate advice. You may decide to use those to supplement the factory manual, but in my opinion they are not a suitable substitute. If you have trouble finding one for your model ask us to help.


TOOLS

WARNING! Do not even try to use Phillips screwdrivers on the Kawasaki cross head screws. Despite their appearance they are not Phillips screws. They are Japanese Industrial Standard (JIS) screws. The tips of Phillips screwdrivers are too long & pointed to allow the 4 blades of the screwdriver to properly engage the screws, so when you apply force the screw head slots will deform and look like crap. The fact is that Phillips screws were deliberately designed to have the screwdriver bit "cam out." This was done to prevent production line assembly from over-tightening, stripping, or breaking the screws. JIS screws do not have this problem. A proper fitting JIS bit can tighten a JIS screw to and beyond the torque spec without camming out. Here's the good news - you can easily modify standard Phillips screwdriver tips to fit the JIS screws.

I have ground down the tips of DeWalt #2 and DeWalt #3 Phillips to make them fit JIS screws. The large crosshead screws on the cases take modified #3 bits (or genuine #3 JIS bits). To modify the DeWalt bits you need to grind the very tip a little, then test fit, then grind a little more and test fit, etc. until the bit no longer "rocks" back and forth in the screwhead. Picture 1 below shows how a DeWalt #3 bit fits the case screws of my KZ650 after being ground properly. The #2 DeWalt bits can be modified the same way to fit smaller JIS screws. Pictures 2 and 3 below shows DeWalt #2 and #3 modified bits.

I did find a place that sells authentic JIS bits. They don't list the #3 bit, but if you contact them they can provide the #3 JIS bits even though they are not listed on the website. These folks were very easy to work with, and the authentic bits do work great. Here's their site:

www.rjrcooltools.com/shop_item_detail.cfm?subcat_ID=89

Pictures 4 & 5 below show a comparison between my home made modified bits with the authentic JIS bits.

PICTURE 1


PICTURE 2


PICTURE 3


PICTURE 4


PICTURE 5


Before reaching for that wrench or ratchet consider the following. The bolts are steel, but your engine and front forks are aluminum. The bolts are much tougher than the aluminum and if over tightened will strip the aluminum threads. Although these can be repaired, preventing damage by applying proper torque will save you grief, time, and money. Tightening fasteners properly requires torque wrenches. Various vendors, including Snap-on, CDI, Sears, etc., market torque wrenches. The two most popular types are the bar type and micrometer type. Either will work, but the micrometer type is a bit easier to use, especially if you are tightening several fasteners with the same torque - such as cylinder head covers. You will need a torque wrench calibrated in INCH POUNDS for many of the bolts. You will also need a torque wrench calibrated in FOOT POUNDS for the larger bolts. Don't try to use the foot pounds wrench on the smaller bolts as it will not be sensitive enough at low torque settings to provide accurate torque. There are many fasteners that require low torque. These include such things as 6mm oil pan bolts, cylinder head cover bolts, etc. for which the torque in 61-78 inch pounds. These low torque bolts require a wrench that is accurate at low settings and this wrench should be graduated in inch pounds. In addition, there are numerous high torque fasteners such as the front axle nuts (51 - 65 foot pounds) or swing arm pivot shaft nuts (58 - 87 foot pounds). These require a wrench that is accurate at higher settings; this wrench should be graduated in foot pounds. Using the proper torque wrenches to correctly tighten fasteners will help prevent damage and contribute to a safe bike. The Kawasaki Service Manual will list the various torque specs for the bolts. I suggest you get the manual before buying the torque wrenches so you can decide which wrenches best meet the torque specs.

Consider buying a can of Kroil penetrating oil and use it to soak stubborn fasteners for a couple days before trying to loosen them. Remember, the original screws and bolts were installed on your bike when Jimmy Carter was President, so many of them may be hard to remove. Kroil can be bought online, at guns shows, and at some other venues.


MOTOR OIL
The ingredients in oils have changed over the years. For example, today's Castrol GTX (and pretty much all AUTOMOBILE oil) is not the same as it was in the 1980's. Back then it worked great in KZ bikes, but things have changed. Zinc and phosphorus additives (ZDDP), important to protect engine components from metal to metal contact, has been reduced since it’s been found to shorten catalytic converter life. Today’s auto oils contain about ½ the ZDDP they used to and different additives have been developed as substitutes. Unfortunately, some of these newer additives, in particular molybdenum disulfide, don’t get along with the wet clutches in our bikes. Newer oils, especially those labeled “Energy Conserving” (EC), which have a high quantity of friction reducing additives, should be avoided. These oils work fine in automobiles but there are better choices for motorcycles.

KZ bikes need oil which is suitable for wet clutches. That distinction was defined by the Japanese Engine Oil Standards Implementation Panel (JASO), and can be noted by oils that meet the "4T” (4 cycle) specification, MA (wet clutch) classification. These oils, which include various synthetic, semi-synthetic, and non-synthetic oils, are sold as specific motorcycle oils. Another type of oil which works well in our bikes is diesel engine oil. These oils are governed by the API (American Petroleum Institute) CI-4/CJ-4 spec and don’t contain clutch-damaging EC additives. You can even purchase Shell Rotella oil which holds a “JASO-MA” certification assuring it will get along well with your wet clutch. All of these newer oils have a reduced ZDDP level too (about 1/3 less than before instead of ½ like the auto oils) but the substitute additives get along better with our bikes needs than automotive oil. Oils that do not hold the JASO-MA rating have either failed the wet clutch test or have not been tested for use in engines with wet clutches. Good luck with the bike! Ed

Here's a pic comparing JIS bits to Phillips bits. Ed

Thank you very much. That does explain a lot. Very detailed and educational. Thank you for the time to put that post up.

I was able to get the broken screw out, with nothing but luck. I was drilling the old screw through (the plan was to drill a hole, then continue stepping up the drill bit and rethread.) However, the bit snagged (I was going slow) and when I put it in reverse, the screws body came out. Thank goodness, that saved me some money. Currently cleaning the carb, and trying to figure out what to do with the stripped screw.

I will most certainly use you advice from now on with removing the screws using a modified phillips bit to match the head. if not, I will not mess with it. Any advice on the jacked up head?

I got one out using the above mentioned method. It appears the previous owner did some work, well, except using phillips head. I will have to get some replacement bolts for this thing.

If the screw head is messed up you make want to try using an impact screwdriver (the type you hit with a hammer). YoIf you don;t own one you may be able to find one that's inexpensive. Here's what I'm referring to:

www.homedepot.com/p/TEKTON-3-8-in-Drive-...dpRgFrQ&gclsrc=aw.ds

Ed

I here you on that... may look into that.

As for the starter, I got it out, tested, and nothing. Rebuilt it, and it works. Bad part... one of the magnets in the body isn't glued to the wall. I am currently changing the fluids and filters... maybe try to start her tomorrow...

WARNING! Do not even try to use Phillips screwdrivers on the Kawasaki cross head screws. Despite their appearance they are not Phillips screws. They are Japanese Industrial Standard (JIS) screws.

Yes, JIS and Philips differ but the blanket assertion of "do not even try..." is not entirely correct.

I used an impact driver - and a Philips bit - ages ago when replacing the clutch on my GPz550. All of the clutch cover screws came out easily and with no damage. I got them started with the impact tool and completed the removal using a Philips screwdriver.

Back to the thread at hand: I would not recommend using an impact tool on any screw stuck in a carb body.

Nerdy wrote: "I used an impact driver - and a Philips bit - ages ago when replacing the clutch on my GPz550. All of the clutch cover screws came out easily and with no damage. I got them started with the impact tool and completed the removal using a Philips screwdriver."

It's possible the phillips tip in your impact driver didn't have the fairly long 19 degree point that most phillips tips have. The diagram above shows that point. That point is what prevents the phillips tip from fully engaging the JIS screw head. In fact, the phillips screw and driver were intentionally engineered to "cam out" (called "throw out" in the patent) when excess pressure is applied, and that camming out is what damages the JIS screw head. The cam out feature was engineered into the phillips screws and tips to prevent damaging the threads on the screws by over tightening; primarily in assembly lines. Here is a quote from the 12/30/1942 patent (#2474994) that describes that throw out issue.

"....Another object of the invention consists in the provision of an improved Phillips type recess wherein the walls to which the driving force of the bit is applied are so angled as to cooperate with the driving walls of the screw-driver bit wings to provide driving torque up to that capable of destroying the thread on the screw before the throw-out force becomes great enough to force the driver out of the recess....."

Regarding using an impact driver on carbs - I fully agree. One is much better off soaking the stuck fastener with Kroil for a couple days rather than risking damage to the carb body. In the case of the OP the stuck screw was in the engine side cover. Even then, soaking it and any other stuck fasteners with Kroil would greatly reduce the chance of damaging anything. Ed

The stuck screw on the carb had the head broke off when I got it... and I was happy to say I got her out. I put the bike together (minus carbs, since I am waiting for parts to rebuild), and wanted to test the starter with the bike load on it.

It turns over... I don't want to start until I have the carbs in for safety. But I am glad to say she turns over after rebuilding the starter. I noticed though that the clutch cable feels really light, like nothing behind it. I see it moving the piece under the side cover, but it just seems like it isn't doing anything. I also notice when the ignition is just in the on position, and I try to shift to first, it doesn't come out of neutral... which I find odd...

I also bought a set of hardware for the 80/81 kz440 to replace those stripped bolts so any further work can be taken care of easier, and to have a bunch of random spare parts.

JIS screw drivers?
Try this link.

www.vesseltools.com/hand-tools/screwdriv...ew-all-products.html




.

And here. www.z1enterprises.com/jis-screwdrivers-s...three-144-244-3.html

Thanks for that link Nebr.

So, good news and bad news.

I cracked the transmission side cover.... (well, it was cracked, and I finished the job)

Good news, found another one with all the clutch actuator with it. This is great because there was one JIS screw that didn't make it, and not in a good way. once that comes in, I will put it in, and adjust that clutch adjustment screw? thing to get the right tension in the lever.

Still waiting to rebuild the carbs. can't wait to put her together and see if she starts.

I have some slack in my chain I need to take care of. I may just get a new chain since this one has a ton of gunk and crapped grease all through it. I may try doing a good clean-up of the chain if I can adjust it enough. I can almost pinch the chain together. Scares me that the PO was riding it like that...