Newly rebuilt KZ1000P engine will not rev...

That's no good. Sorry to hear that the bike Shop wasn't helpful. So now that you have it back, time to dig back in and get it figured out.
Make a list of what you did during your "Rebuild", and any changes that were made. Since it ran OK before it sure sounds as though there is something wrong now.
Also make a list of things checked, whether double checked etc.
These Cv carbs won't get enough fuel without being set up correctly. But then if that lean, having the choke/ enricher on should help it Rev. I don't know if you found another set of BS34 CV carbs to try or not. If you get your valve cover off again, see if the Cam Lobes look like this when the 1-4 "T" mark is lined up. From the right side/ #4.

motorhead the pic is tiny .

leon

If the bike ran correctly prior to the re-build then I would say something was not installed correcty. Did you do the work or someone else? I would double check the cam timing, compression and advance unit myself not rely on someone else telling me they did it. Call me paranoid but I don't trust shops unless their specialty is these old vintage bikes. Modern bike shops do not know these bikes. More reason to learn to work on these yourself.

Motorhead - I'll yank my cam cover again and post some pics. I can't see the one you posted though, it wont enlarge to anything viewable.

Baldy - I did all the work myself. I'm no mechanical slouch, but this is the first motor I've rebuild myself. I did everything per a Clymer's service book, but who know, I'm the first to admit I could have missed something.

Motorhead - Here are some pics for you.

Oh ya, in those photos, the #1 piston is at TDC.

Sorry the picture I posted was microscopic, I nee to get another copy. I think I'll use yours instead, as it looks correct. Cam timing is set correctly as you said.
While you got the cover off I would just re-confirm the valve clearances.
Just remember to remove the tensioner before bolting the valve cover back on, or at least the remove the cap/ spring/ wedge, so the plunger can push back.
I see back in page one, you posted two videos. The second shows the carbs, without air filter connection. I see the #2 slide trying to lift but not the others. I would think that you would see movement on all 4 equally, even without the Filter/ box connections. I know you have stated the slides are in correctly etc. And now the Bike Shop have also done the carbs. You also state the valves are a bit tight but still with in spec. Make sure that they are correct. It sure sounds like it is running with Low vacuum, or the carbs way out of sync. Have you done a bench sync? Where the amount that the butterflies are open are set with a wire gauge, so they are open nearly the same? Also the Fuel level should be rechecked now that the carbs are back from the Shop. Do you have a set of vacuum gauges for running a carb sync?
Do you have a decent inductive pick up timing light? If so put it on each of the 4 plug wires and look at the light flashing. It should remain steady as it runs on each. Kind of a poor mans O-scope.
I don't suppose you could make another video, and post a link to it here? One to You Tube or something where anyone viewing won't have to have an account. Maybe then some light will be shed on your problem, whether its fuel or ignition.

Having just listened to the videos, I'm not even convinced all cylinders are firing in that show. It should be more of a hum or buzz than a putt-putt, but it could just be your microphone in that situation.

diagnostic question - Do you have vacuum caps installed on each carb that doesn't have a vac hose? example: www.oreillyauto.com/site/c/search/Vacuum...p?mn=Edelmann&mc=EDE
If you're not using a vacuum-diaphragm petcock on the gas tank, you don't need any hoses on the carbs. Oh, I forget the smog valve connections, because I lost mine somewhere.

When you say you don't find any vacuum leaks, how did you check - rubber tube stethoscope? Spray test, with WD40 or carb cleaner? Spray test has revealed hidden carb boot leaks to many on this forum.

Carb sync - if you can get a couple cheap automotive type vacuum gauges, you can look at the carb sync. Consider that the carb sync is in tune with the engine's capabilities/needs/demands, but the rebuild has changed the engine; carb sync is necessary. it is necessary to check it after each jetting change as well. With 2 gauges you will only look at the carbs you are specifically syncing -- first 1 and 2, then 3 and 4, then 2 and 3 to balance the two sides. it will get you close.

carb slides - if you blow compressed air into the long port on the top of the intake side, the slide should rise. I usually do this with the carb rack on the bench, so I'm not sure how well that works when its on the bike.

Not vacuum related - Have you checked the operation of the mechanical timing advance mechanism?


HTH,
Ricky

Motor Head - I can take another video, exactly what would you like to see? Anything specific that might help you out?

Rickman - I used carb cleaner to check for vacuum leaks, don't have any reliable gauges. Probably should fix that... Anyway, the boots are brand new and sealed to the head. My vacuum lines are as follows: all new, first off. #1 and #4 link together and run up to the vacuum valve going into the cam cover. #2 operates the petcock, and #3 is capped. We did a synch when I first took it into the shop, to no avail. Carb slides rise as you described, and I cleaned then polished the ignition advance.

I'll post a better video soon. Thanks.

Do you have an Inferred Thermometer? If not Harbor Freight has one. Then you can check the temp at each EX pipe at the head. Which will show if they are heating evenly/ firing. Also did you do the Inductive Timing Light check? Each Plug Wire to see if all 4 have consistent spark? This way if there is a coil or ignitior problem, it will likely show up. Did you replace the Plug wires, or the spark plug caps?
Like I said I would Make a List of everything that you did. Then what you have checked and confirmed correct. Try to rule out as you go. With Good Compression, and Cam Timing correct, you still stated the Valve Clearance was on the tight side of Spec. Have you got that re-checked? Post the #'s.
For the Video. Just let it Idle, as smooth as you can get it, showing the Temps on each pipe.
Then another with you trying to Rev it. Will it just die if you grab a handful?
Are you Adjusting the Idle Mixture Screws? They should be about 2 turns out from lightly seated but may need either more or less turns out. the manual will be 1 1/2 turns. But that's a starting point really, each carb can be slightly different.

roman_dog wrote: My vacuum lines are as follows: all new, first off. #1 and #4 link together and run up to the vacuum valve going into the cam cover.

OK good stuff, stock setup. But that emissions valve doesn't leak, does it? What about capping all of the vacuum nipples and run it with the PC in 'prime'?

Motor Head is right about checking downpipe temperature to see if cylinder's firing; the IR thermometer is good, also you could use a spray bottle of water/something waterbased and hit each downpipe with it - after just a short time idling the engine, the water should instantly boil off of the pipe; on cold pipes the water runs down.

HTH

Edit:
I just saw this interesting post in another thread, relevant to my line of questioning...

Steve1986 wrote: the cylinder has to do with emissions(for u.s. bikes) it only allows my bike to run when its hooked up a certain way. if messed with or plugged would bog my bike or just not let it start ...