I used to do a precision valve clearance adjustment on my 1976 KZ 900: 1. set the valve clearance as specified here, with an extra .001" on the exhaust valves - this gets you close 2. bolt a degree wheel onto the crankshaft and use a dial indicator to mark TDC on cylinder 1 3. put the dial indicator on each valve shim and record the amount of lift at the specified #of degrees BTDC for the intakes and #degrees BBDC for the exhausts 4. seek to equalize the valve lift for all intakes by sanding the shims down on the 3 shims that have the highest lift, do the same for the exhausts Precision synchronization of the carbs: 1. synchronize intake port vacuum with "carb stix" with the engine a little above idle - this gets you close 2. run the engine up to a rpm where it can run smoothly on 3 cylinders(~2000 rpm) and then short out one of the cylinders, record the rpm drop 3. do the same for the rest of the cylinders 4. increase the throttle opening in the cable adjuster a very little for the cylinder that had the least rpm drop 5. repeat the process until you can get an equal rpm drop from each of the cylinders that is shorted out. Your Kaw will now have a super smooth running engine. If interested I can post a tip on precision cam chain tension adjustment.
@@zeke2566 That was step 1, setting the valve lash the factory recommended way with the appropriate thickness shim. It works well and there is nothing wrong with stopping there. If you then measure the valve lift at the point specified of crankshaft rotation you will see that each valve has a slightly different amount of lift. Replacing any of the valve shims with the next smaller shim size will not get you exactly where you want to be, because of the size of the increments of the discs that are available.
@@zeke2566 In terms of the benefit gained, for the additional amount of work put in, it's probably not worth it for most applications, TBH. The thing I noticed on my Kaw was that the engine was slightly smoother running after the precision valve lash and carb synchronization. For me, it was probably motivated by my curiosity to see if such an effort would produce a noticeable benefit. As you said, perhaps the difference might have been more pronounced on a multi-valve race engine that's turning 14k rpm.
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I used to do a precision valve clearance adjustment on my 1976 KZ 900:
1. set the valve clearance as specified here, with an extra .001" on the exhaust valves - this gets you close
2. bolt a degree wheel onto the crankshaft and use a dial indicator to mark TDC on cylinder 1
3. put the dial indicator on each valve shim and record the amount of lift at the specified #of degrees BTDC for the intakes and #degrees BBDC for the exhausts
4. seek to equalize the valve lift for all intakes by sanding the shims down on the 3 shims that have the highest lift, do the same for the exhausts
Precision synchronization of the carbs:
1. synchronize intake port vacuum with "carb stix" with the engine a little above idle - this gets you close
2. run the engine up to a rpm where it can run smoothly on 3 cylinders(~2000 rpm) and then short out one of the cylinders, record the rpm drop
3. do the same for the rest of the cylinders
4. increase the throttle opening in the cable adjuster a very little for the cylinder that had the least rpm drop
5. repeat the process until you can get an equal rpm drop from each of the cylinders that is shorted out.
Your Kaw will now have a super smooth running engine. If interested I can post a tip on precision cam chain tension adjustment.
Why sand shims? Replace with correct sizes.......
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@@zeke2566 That was step 1, setting the valve lash the factory recommended way with the appropriate thickness shim. It works well and there is nothing wrong with stopping there. If you then measure the valve lift at the point specified of crankshaft rotation you will see that each valve has a slightly different amount of lift.
Replacing any of the valve shims with the next smaller shim size will not get you exactly where you want to be, because of the size of the increments of the discs that are available.
@@videomaniac108 I can see advantage of your method on a 4 or 5 valve per cyl race bike but on a 2 valve street bike -not really
@@zeke2566 In terms of the benefit gained, for the additional amount of work put in, it's probably not worth it for most applications, TBH. The thing I noticed on my Kaw was that the engine was slightly smoother running after the precision valve lash and carb synchronization. For me, it was probably motivated by my curiosity to see if such an effort would produce a noticeable benefit. As you said, perhaps the difference might have been more pronounced on a multi-valve race engine that's turning 14k rpm.
@@videomaniac108 agreed! I bet you build one hell of a race motor too!
Love it! This bike changed everything when it came out.
beauty, the best on you tube, love to see more like this, thank you for sharing your know age .your Good !
The best video on UA-cam, thank you!. Good work by good people.
This is a classic vid!
great video, very informative, refresh in rebuilding
easy to rebuild simple engines
genius
Amazing.