how to measure valve clearance

I've got one of my bikes valve covers off (84 Kz550 ltd) I've read in two different manuals on how to measure the valve clearances, one of them showing the cam lobe pointing directly away from the bucket, and another manual showing the lobe parallel to the block. So my question obviously would be.. Which one is correct?

I went through my first valve adjustment procedure on my '82 550a.

I'm guessing the manual that shows your cam lobe pointing straight up is the Clymer.
The manual showing your cam lobe pointing parallel to the head's gasket surface is a FSM?

The latter is the one to follow. It seems based upon others on the forum with more experience that the Clymer manual is not entirely accurate.
I tried measuring both ways (using the lobe-up way first before I knew about this issue) and then the lobe parallel to gasket surface and got two different results. I chose to follow the FSM and the guys here recommending to be leary of the Clymer.

Personally, I found the clymer manual useful to have next to me in the garage while doing the work because it seemed easier to me to find the details and the drawings pictures were sometimes better (IMHO) but I deferred to the FSM for specifics (like lobe position and process for when to measure).

Good luck. I ended up doing the job 4 times before it was all said and done. I'm no longer nervous about the process

Use the factory manual method. It puts two adjacent valves on the base circle at the same time.

One key thing to know is to remove the cam chain spring tensioner cap which allows the tensioner to move in and out before you put the valve cover on. Otherwise you will over tension the cam chain.

Neither are Clymer, however I literally just noticed the lobe up position is in the manual for 79-85 and the parallel lobe is in the manual 79-83.. Ugh.

kayodash wrote: Neither are Clymer, however I literally just noticed the lobe up position is in the manual for 79-85 and the parallel lobe is in the manual 79-83.. Ugh.

Factory manual? I've never seen any method in the factory manual besides the TDC method.

As Nessism mentioned, use the Factory Service Manual method, I have links to several in my signature. The red base manual and white base manual both specify TDC as the point to take the measurement.

(I'll try to check the supplements.)
EDIT: A quick scan shows all to say use the "T" mark, which is TDC. (If the head is not on the engine, use the cam sprocket timing marks with the valve cover deck as the reference point.)

It is odd that the supplements have the valve adjustment procedures since they all seem the same. Normally, if info in the base is the same for later years, the supplement won't repeat the same info.

Also, as he mentioned, read the valve train warning in my signature for details about the valve cover install.

I actually got the manuals from your links. Does it not matter the orientation of the camlobe as long as the Motor is TDC? Like do I just rotate it to TDC and measure regardless of which way the lobe is pointing?

loudhvx wrote:

kayodash wrote: Neither are Clymer, however I literally just noticed the lobe up position is in the manual for 79-85 and the parallel lobe is in the manual 79-83.. Ugh.

Factory manual? I've never seen any method in the factory manual besides the TDC method.

As Nessism mentioned, use the Factory Service Manual method, I have links to several in my signature. The red base manual and white base manual both specify TDC as the point to take the measurement.

(I'll try to check the supplements.)
EDIT: A quick scan shows all to say use the "T" mark, which is TDC. (If the head is not on the engine, use the cam sprocket timing marks with the valve cover deck as the reference point.)

It is odd that the supplements have the valve adjustment procedures since they all seem the same. Normally, if info in the base is the same for later years, the supplement won't repeat the same info.

Also, as he mentioned, read the valve train warning in my signature for details about the valve cover install.

Would the valve cover install be the same for a 650 as well? Need to follow your instructions on the warning page as well? Need to replace my gasket and fairly new to me bike. I came from working on newer bikes.

Thanks!

I prefer measuring the valve clearance gaps with the cam lobe pointed directly away from the shim, which unquestionably assures the lowest cam position.

Removing the spark plugs before measuring makes it much easier to position the cam by hand-rotating the crankshaft via turning the 17mm fake nut that's provided for that purpose -- not the smaller 13mm bolt head that's screwed into the end of the crankshaft which risks shearing it off.

I suspect that the TDC crankshaft position mentioned in the manuals might be to accommodate being able to measure more than one valve before having to again rotate the crankshaft.

Good Fortune!

MediumB wrote:
Would the valve cover install be the same for a 650 as well? Need to follow your instructions on the warning page as well? Need to replace my gasket and fairly new to me bike. I came from working on newer bikes.

Thanks!

PLEASE add your bike's exact year and model to your signature line. The correct answer to your question, and in fact to most questions, depends on exactly which year and model bike you have. Not all KZ650's are the same. Ed

Added. I know the 79 and newer has an auto adjust and nothing is needed. Per Clymer and FSM it would appear I need to run through the entire cam process to ensure I don't detonate the chain, guides or camshaft. Just wanted some fellow confirmation.

kayodash wrote: I actually got the manuals from your links. Does it not matter the orientation of the camlobe as long as the Motor is TDC? Like do I just rotate it to TDC and measure regardless of which way the lobe is pointing?

The manual specifies which valves to measure for each of the two TDC positions. It specifies possible pairs of intakes and possible pairs of exhausts because one pair will be measurable, and the other pair will not be measurable (based on lobe position). To do the un-measurable pair will require a full crank rotation.

550 valve timing is symmetrical, so you may notice that the lobes are mirror images (or close to mirror images when the valve cover is removed), but only at TDC (or BDC) depending on which cylinder you are looking at.

The manual specifies all of this in the text. You must read the text of the procedure, not just the instructions in the chart.

The factory manual puts two adjacent valves on the cam base circle at the same time. This is critical. If you point the cam away from the bucket the adjacent valve will be depressed and the reaction force will push the camshaft away from the valve and skew it within the camshaft journal clearance. In other words, the factory method will show a smaller lash measurement compared to pointing the cam lobe away from the valve and measuring that way.