kz750 ltd h2 1981 - will crank wont start fully?

steelhorseangel wrote: "ed disagree's with boyer about the timing degrees etc"

I don't recall saying anything about boyer's timing degrees instructions? The only time I even mentioned the word timing in this entire thread was when I found it odd that the boyer folks said you needed a separate battery to use a strobe, and in that posting I recommended you follow their advice since they made the ignition system. Here's the posting:

650ed wrote: "If they made the ignition system I would follow their advice. I have been performing my own tuneups on my KZ650-C1 for 35 years and never have I even heard of using a separate battery; it certainly is not required when using Kawasaki the stock ignition on my bike. All the strobe does is sense the firing of the spark plug (using the inductive pickup clamped around a spark plug wire) and upon sensing that it completes the power circuit from the battery that triggers the strobe light. I guess it's possible that the Bransden electronic components are so sensitive that they are affected when the strobe pulls power from the bike's battery. I wonder if the timing gets squirrely when the turn signals are used?"

Angel, does your timing light/gun, have an advance wheel/digital controls? (For settings degrees).

The Timing instructions from Boyer talks of having a degreeing wheel (which I am assuming you dont have...) for attaching to the crank and using to mark ignition cam.

This doesnt really help you that much for inital advance, which would be lining up your case mark with the "F" mark on the ignition cam.
They are talking about Full Advance, which happens after teh bike revs up past 3500rpm or so. The advancer changes the spark from around 10, to 40 degrees before TDC (in a smooth arc of progression) for proper operation.

To check your timing, you must first aquire a degreeing wheel.
Set TDC for 1-4 accurate as possible, install degreewing wheel, then advance motor 320degrees, and place a corrosponding mark on the ignition cam in direct relation to the case mark.
Then do the same for 2-3.
Then with engine running, and revving bike out to where full advance occurs. Look with timing light, and the mark you made should line up with the case mark (hence 40degrees full advance).

If it is to the left of the mark, you need to rotate your ignition plate counterclockwise slightly and retry, opposit for if its on the right of course.

I realize this is a bit crazy and complicated, but we can walk you thru it if you get a degreeing wheel.

Best of luck - you're almost there!

PS - the colder cylinders is "probly" not related to timing, and more so related to carb/air leak/etc.

hi tek.

thank you for your reply!

no my timing light is a simple one.
it has an inductive connector, croc clips.
it doesn't have a timing wheel.
i did download one in *.pdf format.
one was marked clockwise, the other is
anticlockwise.

i think i understand the mechanics, here
goes in rookie speak.

the engine is divided into two, each half
has two cylinders = 180 degrees. this
could be #1 & #4 or #2 & #3. as one half
goes up, the second half goes down.
each pair of cylinders have a different
timing mark.

q) are both timings marks for 1,4 & 2,3
marked on the stator engine casing?

boyer hasn't come back to me yet.
i sent them some more questions today.

boyer advise 40deg adjustment. that's
20degs per 180degs. so that equates
to 160 per rotation, clockwise or anticlockwise?
160*2=320
320+40=360

i wish that i could see one of you
guys adjust your timing!

clockwise or anticlockwise?

many thanks

Angel

hi tek
how can i see two timing
marks for 1&4, 2&3 when the stator plate
is covering up the timing plate and the magnetic
rotor wants rip your hand off!

could you do a simple drawing please!

do i turn the engine clockwise or anticlockwise?

what do the marks 1 l 4 mean on the
timing plate?

i can see why mechanics are always busy!

many thanks

Angel

hi again!

i've just thought about the kz engine it can
only go one way, ccw or the big bolt would
unscrew, lefty loosie, righty tighty!

on the honda goldwing, it has a reverse gear.
we should have a reverse on a kz!

had a busy week, a blonde moment!

clockwise!.....

must sleep! zzzzzzzz shattered zzzzz

To Advance the timing, more degrees Before Top Dead Center (BTDC), you turn the Ignition plate against the direction that the engine turns. So that means looking at the Plate, turning it to the left, or anti-clockwise would advance the Timing. So then turning it with the direction that the motor rotates retards the timing, clockwise.
The 1/4 mark, will have an "F" that will line up with the permanent case mark, when engine is running and your timing light is connected to the #1 or #4 cylinder. The Brandson Ignition should have a hole, at the top for looking through to see this. First do it by hand, with the motor off. See the timing marks line up as you turn the motor over with the 17mm nut. If it will help, you can make a mark, on the 1/2 side of the rotor, showing where the "F" would be for 1/2. Since you probably don't have a degree wheel, the simplest way would be to measure the distance between the marks there already for 1/4. This would be the distance between 1/4's TDc "T" mark and the "F" mark. Then make a mark at 1/2 thats the same amount of distance out from the "T" mark on 1/2. This will be close to correct, the more accurate the measurement the better. Then setting the 2 pick-up magnets that are on the Brandson plate can be done. Each will have a small adjustment possible, so you want both the original "F" mark on 1/4, and the mark you made for "F" 1/2 to line up at Idle. The 40 degrees talked about is total advance. This is when the engine speed is above 4.5K RPM. The advancer moves the timing through weights and springs further to the advanced position as the engine speed increases. It does this over a curve. If you had the light with a wheel or digital advance built in it would be easier, but you can make your 1/2 "F" mark and set it up anyway.

Sorry for delay, been very busy!

Your thoughts on the engine are correct. Almost all inline fours are the same configuration.
When the 1-4 cylinders are at Top.Dead.Center, the 2-3 Cylinders are at Bottom.Dead.Center
The 1-4 cylinders @ TDC will be either at the top of the exhaust stroke, or the compression stroke.
The 2-3 cylinders @ BDC will be either at the bottom of the power stroke, or the intake stroke.
The crank turns in exact relation to the pistons. If you think of your engine as four little 1 cylinder engines connected together its easier to imagine. The cylinders fire in the order of 1, 2, 4, 3 - and this just repeats over and over.



Spark must happen Before.Top.Dead.Center (BTDC) for normal operation on the compression stroke. Our systems fire spark on both assigned cylinders at the same time. 1-4 fires to light the compression on cyl 1, and wastes a spark on the exhuast stroke of cyl 4 for example.

There is an excellent animation here: www.howstuffworks.com/engine1.htm the arrow on the map at the right is the point the plug sparks.

Soooo, after all that.

What your trying to do is confirm that spark is happening at 40 degrees BTDC at full advance.
As I explained before, spark needs to advance as engine speed advances up to a certain point.
depending on the use/type of engine, inital advance wil be around 10degrees. As the engine begins to rev up, the engine slowly advances the spark timing till it reached its maximum advance. Which in your case is 40degrees at approx 3500rpm+ engine speed.

So you could just use a protractor:


Set cylinders 1-4 at TDC - (Stroke doesnt matter cause both plugs fire rememeber).
For our sake, we pretend the 90degree mark (perfect verticle) line on the protractor is 0 degrees. the line showing 130degres is, for our purposes, showing 40degrees advanced.

Line up zero degree mark (90) with your case mark (0 degree mark when cylinder is at TDC) with protractor centered over your crank.

As indicated on the protractor picture, 40 BTDC (130degree line) is where you need to make a mark on your ignition rotor/cam (part that spins that you can see thru the ignition plate hole).

Then, do the same thing for 2-3 cylinders at TDC.

NOW: hook up timing light. Start your engine.
When you rev the bike and hold above 3500rpm. The 40degree marks you put on the rotor/cam, should line up with the case mark, as seen thru the hole in your ignition plate.
The timing light should flash every time and never miss, giving you a clear strobed view of the case mark and the mark you made on the cam/rotor lining up.

If they do not line up, your timing is off. Simply rotate your ignition plate, until the marks align.

Good luck! hope this helps fill any gaps you are pondering.

steelhorseangel wrote: hi tek
how can i see two timing
marks for 1&4, 2&3 when the stator plate
is covering up the timing plate and the magnetic
rotor wants rip your hand off!

could you do a simple drawing please!

do i turn the engine clockwise or anticlockwise?

what do the marks 1 l 4 mean on the
timing plate?

i can see why mechanics are always busy!

many thanks

Angel

The timing light will flash showing the 1-4 marks thru the hole when you have it connected to either 1-4 plug wires. then when yuo move the timing gun to the 2-3 plug wires, it will flash, showing the 2-3 timing marks thru the hole.

The 1-4 mark on the timing plate indicates those cylinders. There is usually an "F" mark on the rotr/cam that indicates when the plug Fires, just before (to right of) "T" mark which would indicate TDC for those 1-4 cylinders.

steelhorseangel wrote: clockwise!.....

must sleep! zzzzzzzz shattered zzzzz

Yes, clockwise LOL - always with larger nut, not the rotor bolt.
The engine should always be rotated in teh direction of normal travel.

steelhorseangel wrote: q) are both timings marks for 1,4 & 2,3
marked on the stator engine casing?

The case mark indicates only TDC.