Kz400 H82 Cam / Timing refitting. 100$ reward paid for solution

One thing to remember is that timing chains don't shrink ever. They stretch. The taught side of the timing chain, as we view a 440 twin cam timing, is on the left side. That is the side that matters, and we have to assume after all these years that is has either stretched or possibly is at the correct length.

The arrow, then , on the sprocket should never point above the valve cover deck. It should point directly at the deck surface or very slightly below.

Before we judge the position of the sprocket arrow we need to align the T mark on the advancer. Yours appears close, but in the photo it does not appear perfectly aligned.

The proper way to take such photos is to back the camera far away on a tripod and make sure the lens axis is on the same axis as the crankshaft or camshaft, which ever one is being photographed. Then zoom in to make the image bigger.

This flattens out the image and then proper timing can be judged. Sometimes to see the marks and the deck both, you might need to come off axis a bit, but still close enough to get a good representation.

To me, looking at the photos as is, both photos appear to show the arrow slightly upward. When the advancer is lined up perfectly, I would expect the sprocket arrow to be slightly downward.

And yes, your engine at the very least, uses a 440 valve train.

loudhvx wrote: One thing to remember is that timing chains don't shrink ever. They stretch. The taught side of the timing chain, as we view a 440 twin cam timing, is on the left side. That is the side that matters, and we have to assume after all these years that is has either stretched or possibly is at the correct length.

The arrow, then , on the sprocket should never point above the valve cover deck. It should point directly at the deck surface or very slightly below.

Before we judge the position of the sprocket arrow we need to align the T mark on the advancer. Yours appears close, but in the photo it does not appear perfectly aligned.

The proper way to take such photos is to back the camera far away on a tripod and make sure the lens axis is on the same axis as the crankshaft or camshaft, which ever one is being photographed. Then zoom in to make the image bigger.

This flattens out the image and then proper timing can be judged. Sometimes to see the marks and the deck both, you might need to come off axis a bit, but still close enough to get a good representation.

To me, looking at the photos as is, both photos appear to show the arrow slightly upward. When the advancer is lined up perfectly, I would expect the sprocket arrow to be slightly downward.

And yes, your engine at the very least, uses a 440 valve train.

Again , first and foremost thank you for your time.

So if we are on the same level here you mean the advance should be just a touch to the right to line up perfectly, and the chain maybe a tooth further downwards ? i will try to correct the advancer a quarter mm or so to get it perfectly aligned, and then adjust the tooth on the chain and try to take some picture from a good angle with decent light

Allthough a smidge confused because @Nebr_Rex mentions that the arrow on the sprocket should be slightly above the head but you mention slightly below or at the very least level and not upwards, and the prints from above also makes it look like it should face slightly downwards or level depending on what angle your engine is viewed at i guess.

Ok so i have taken some new pictures, when the cam chain back to the crank is tight and fully engaged the timing mark lines up perfectly. The only question remaining is this, i have taken two new photos, as you can see once i parallel with the top, and one i moved the chain one tooth over and it is slightly downwards, one of these according to all the info in this thread should be correct ? unless you could mess it up with the wrong TDC that is there is technically two right since you are supposed to rotate it two revolutions to see if it lines up after, or does it not matter because both are TDC im guessing the latter, so here it goes see pictures below.

i guess i could just try both and see what works best, but i would really like to not put it together and take it apart for the 17th time if i can help it.

as always any and all help is appreciated.

Given the theory about the chain becoming more loose over time, would that move the arrow further down or up when timing , working under the assumption that there is a little bit more slack after almost 40 years :woohoo:

The arrow on the cam sprocket should not point down.
I have check the cam timing on several KZ400 and KZ440s with a degree wheel.
They have consistently shown about a one degree in chain stretch.
The cranking compression specification for these engines is 155 p.s.i. .
If you are curious about which on is correct.

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Nebr_Rex wrote: The arrow on the cam sprocket should not point down.
I have check the cam timing on several KZ400 and KZ440s with a degree wheel.
They have consistently shown about a one degree in chain stretch.
The cranking compression specification for these engines is 155 p.s.i. .
If you are curious about which on is correct.

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Ok you had a look at my picture so do you feel like the level one is the correct setting from the new pictures i took, making it level to the top, or would you actually go an extra making the arrow on the sprocket not level but slightly upwards? sounds like we are reaching and agreement here but technically there are stil three options on the table either slightly down, parallel to the top or slightly above. am i missing something here or could you just give me one last school session judging from my recent pictures level, or slightly above - given what you mention with 1 degree in stretch should that effect the arrow on the sprocket upwards or barely noticeable.

i would appreciate from all the pictures and documentation and videos i have provided if you could just give your personal opinion on where you would put it and add that picture to your reply so i can try with that tomorrow. but im pretty sure i have tried level before with these problems but who knows.

Level with the head is the stock position.
I would advance the cam one tooth.
For more on my reasoning for this opinion start reading on page twenty of this link.

www.dotheton.com/forum/index.php?topic=39120.190


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Nebr_Rex wrote: Level with the head is the stock position.
I would advance the cam one tooth.
For more on my reasoning for this opinion start reading on page twenty of this link.

www.dotheton.com/forum/index.php?topic=39120.190


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SO advance meaning that the arrow in the sprocket faces slightly upwards and not downwards or even parallel right - am i understanding you correctly ? because this may be the only thing i haven't actually tried yet.

thanks for your insights on this , i really appreciated it - if you confirm this i will go ahead and try that tomorrow and hopefully it will turn over and run. if that in fact works keep your paypal info handy im a man of my word if this thing works out now i'm a man of my word 100$ it is .

but if that dont work im gonna dial it back to level try again and if not, i'm gonna dial it back another tooth so it is slightly below just to test every possible way, but i'm hoping this will be it

Yes up is advanced.
Be sure to read the information in that link.


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If we assume the sprocket arrow lines up perfectly when the motor is manufactured, then assume the chain has stretched over 40 years, the sprocket arrow would point slightly lower than when it was new. This assumes the timing advancer is set perfectly when new and old.

When I say "slightly", I mean by much less than one tooth.

If the motor has very low miles and the chain did not stretch, then we would expect the marks to be in the same place they were when new.

If you can get the arrows to line up perfectly, then that is the way it came from the factory. Your first photo shows that is how you have it. Pointing downward by a full tooth would be retarded by one tooth. Upward a full tooth would be advanced by a full tooth relative to the stock timing. I've never ran a 400 or 440 with altered timing, aka non-factory timing, so you'd have to take Nebr_Rex's suggestion on which way to run it. I would not run it a full tooth retarded (arrow down) unless you can get confirmation the piston has no chance of hitting the intake valve.

Just for reference, this is the opposite condition with inline-four cylinder Kz's, because those motors rotate in the opposite direction, but the timing marks are in similar positions. So as the chain stretches, the arrow starts to point above the valve cover deck on inline-four Kz's.

so i just did this - advanced it one tooth , crank in TDC exactly i then whent from perfectly level to the top (sprocket arrow) to slightly upwards, it started up but i had some carb farts on the left side carb (like back firing out the air filter sort of ) from time to time, could no get it to idle unless high and then it would chase for a while after giving gas before returning,, but then i got an idea - the pilot jet screw / fuel adjuster, should that have a o ring inside or some kind of gasket inside it ? because in my rep kit i saw both a oring that fit the jet and some sort of disc in metal that also seemed to slide over the jet going inside before the end where the threads are, and there might of course be the old ones inside there i need to check that, but if so this is maybe where the problem lies now assuming the timing is in fact suppose to be the way you mention and not the way @loudhvx mention.

Thing is i can not find this outlined in any part manual or anything exactly what goes where in the carb rep kit. would be nice to have a picture showing all of this.

Btw Nebr i whent through your entire link and it made sense have you said but again like mentioned by the other member the advancement should maybe be so little that a whole tooth may be overdoing it but then again there is no other way to do it when in TDC then to go one tooth back or forth.

goatfarming wrote:
Thing is i can not find this outlined in any part manual or anything exactly what goes where in the carb rep kit. would be nice to have a picture showing all of this.

This should answer your question



BTW, your 100$ reward paid for solution should be a donation for KZR community, just a thought.