Points adjustment - help a noob

So I'm reading my manual on how to set the point gap for my 1979 KZ750 twin. The bike starts and runs, it's just a little rough and I'm trying to check that everything is set to spec.

There are a couple things in the manual that may be obvious to the more mechanically experienced, but are not clear to me.

It says to clean the points with a business card soaked in an oil free solvent like trichloroethylne. I don't have anything in my cabinet called trichloroethylne. What else can I use?

It says to lubricate the point cam oil felt with "suitable point cam lubricant". What exactly would be suitable? Can I use motor oil? My felts look bone dry.

Also, it says to turn the crankshaft counterclockwise until the contact breaker points are at their widest opening.

When I turn my crankshaft I don't see the breaker points move. How much am I supposed to turn it? I went for one full rotation and didn't notice any movement. Am I not watching closely enough? Do I need to keep turning?

Topper wrote:

So I'm reading my manual on how to set the point gap for my 1979 KZ750 twin. The bike starts and runs, it's just a little rough and I'm trying to check that everything is set to spec.

There are a couple things in the manual that may be obvious to the more mechanically experienced, but are not clear to me.

It says to clean the points with a business card soaked in an oil free solvent like trichloroethylne. I don't have anything in my cabinet called trichloroethylne. What else can I use?

It says to lubricate the point cam oil felt with "suitable point cam lubricant". What exactly would be suitable? Can I use motor oil? My felts look bone dry.

Also, it says to turn the crankshaft counterclockwise until the contact breaker points are at their widest opening.

When I turn my crankshaft I don't see the breaker points move. How much am I supposed to turn it? I went for one full rotation and didn't notice any movement. Am I not watching closely enough? Do I need to keep turning?

I use 'electronic parts cleaner' to clean points -- it's in a spray can. Maybe you can use IPA (isopropyl alcohol, aka 'rubbing alcohol') that almost any female (girlfriend, spouse, sister, etc.) will have available. Or a bike hobbyist will have IPA. IPA is good for cleaning o-rings in brake calipers, lots of uses. IPA and electronic parts cleaner are both considered 'oil-free solvents' I believe.

As to the business card -- I bought a set of small precision flat files to use to clean points. A business card should give enough abrasiveness for most points cleanup though I suspect.

You can use a medicine dropper and put a light oil on the felt, maybe just one drop; household oil, or if you're a guitarist, fretboard oil maybe.

The points should open when the correct marks appear -- see your manual for identifying the timing/firing marks and you'll see that the points should open at specific times. Keep turning the crank until those specific marks appear and then check the point gap.


If the points 'never open', make sure of that by (easiest way) put your 'line of sight' horizontal to the floor at the points level, ie. lay on your side -- idea is to *not* look at downward-gazing angle at the points, you might miss the opening -- get your eyeballs in position *directly next* to the points to really assess this. Or -- just use your manual to find out how to widen the point gap, and widen the gap enough so you see the gap opening, then reduce the gap (following the adjustment steps given in the manual) until the gap size is correct.


Generally, your manual will probably have you
1) set the points gap first
2) then set the timing

and that's one thing eliminated that can affect how the engine runs.

Note there is an adjustment for the gap, and another separate adjustment for the timing.

This image is for a four cylinder, but should help visualize the process.

I also use a drop of oil on the felt, but more particular guys use a special points cam lube.

The business card is sometimes used as a thickness reference to guesstimate a gap setting where the proper thickness gauge isn't available. Folks without business cards just use a match book cover. I'm uncertain about just how non-smokers without business cards or thickness gauges should approach this.

The contacts may be "dressed" with a points file to gain a smoother interface. I prefer to dress points by using a small folded strip of fine sandpaper to push-pull between the closed contacts.

After dressing, clean the contacts, set the gap, tighten the adjustment, re-clean the contacts, and then proceed with timing.

Good Fortune!

[Click on image to enlarge the view.]

Don't use motor oil; it won't stay put. You should use distributer cam lube. This is NOT the same as dielectric grease which is not a lubricant but a sealant used for electrical components. The youngsters at the auto parts counter won't know the difference because they are not familiar with points ignition systems. Here are a couple ignition cam lubes:

Bosch

Mallory

Oh, and don't go crazy with the grease; a little goes a long way. Ed

Well the reason I couldn't see the point gap opening was because it was barely opening. Spec is 0.35mm and the gap was more like 0.025mm.

Thanks for the help. I'll have to pick up some distributor cam lube next time I'm at the auto parts store.

Now on to timing adjustment.

Thanks for all the help everyone.

yea i have the same bike and did the adjustment last weekend..did about .35mm also...thats a good bit open..can easily see it...

i have timeing to do now when i get her running well enough..

Good luck

be careful when you are setting worn points with a feeler gauge. When points wear, material is transfered from one contact to the other. This results in a pit in one contact, and a lump on the other. If you don't file that lump off, you will not be able to set the gap correctly. It is not always possible to completely file the pit away, but you do need to get rid of the lump. Anybody here using a dwell meter? I would love to hear a breakdown of how to do this on a KZ. You can really dial in the points on the old chevy's where they have an allen adjuster so that you hook up a dwell meter and adjust with the engine running...

seanbarney41 wrote:

Anybody here using a dwell meter? I would love to hear a breakdown of how to do this on a KZ. You can really dial in the points on the old chevy's where they have an allen adjuster so that you hook up a dwell meter and adjust with the engine running...

Yes, I use a dwell meter on my KZ650. The KZ650 shop manual provides good instructions on it, but the dwell angle spec(185-195 degrees with dwell meter set for 1 cylinder engine) may be different for the KZ1000. Using the dwell meter allows you to set the points gap more accurately than using a feeler gauge, although for years I used only a feeler gauge with satisfactory results. Just be sure to compensate by multiplying the actual reading by the dwell meter cylinder setting if your dwell meter doesn't have a 1 cylinder setting on the selector knob. Ed