That sounds like REALLY BAD cam chain noise to me. My 2002 started making a noise similar to that at around 15,000 miles, but nowhere near that bad. I replaced the ACCTs with new ones from Kawasaki. The noise went away for about 10,000 miles, then started to come back. I switched to TOC manual cam chain tensioners. It never made that noise again, but the engine eventually did fail due to a broken cam chain. I suspect that some damage was done early in the engines life, when it was making that noise. I examined the oem ACCts very carefully, and found the internal threads in the aluminum casting were almost completely destroyed. One thing you can do to check that is to take a pocket screwdriver, remove the cap from one of the tensioners, and with the engine running, stick the screwdriver into the end of the tensioner. if the plunger knocks the screwdriver out of your hand, the tensioner is completely shot. The tensioner body has internal female threads cast into it (it's made of soft aluminum) and the plunger that is designed to press against the chain guide and keep the chain tensioned has external male threads on it. It is made of steel. There should be almost no play between the threads in the housing and on the plunger. But as the cam chain turns on it's sprockets, it does so with a whipping motion, constantly banging against the plunger, which quickly wears out the soft aluminum threads in the tensioner housing. The tensioner is now toast, and that is where the problems begin. The plunger binds in the housing and no longer moves in to take up cam chain slack. This could probably have been prevented had Kawasaki used steel for the tensioner body instead of aluminum. But they didn't. Normally I would suggest replacing the stock tensioners with TOC tensioners, but from that sound, I believe the cam chains and guides are probably to far gone to make it worthwhile. It would likely fail after a short time anyway, even if you got rid of the noise.
There is a way to convert the ACCTs to MCCts . I definitely don't recommend it on a good engine, but it costs almost nothing, so it might be worth a try. The instructions are on here somewhere. Just remember that if the engine does fail due to a broken cam chain, it can lock up, and lock up the rear wheel in the process. Mine locked up for maybe a second, then the broken chain shattered the aluminum engine casting, and it started turning again.
This is just how complicated the cam drive system is. https://www.cheapcycleparts.com/oemp...ft-s-tensioner
It's an absolute nightmare. Part #12048 are the tensioners. $100 apiece for junk.
These defective cam chain tensioners, having to pull the engine to replace the stator, and the fact that the factory never lubed the final drive splines on most Vulcan 750s are probably the reason there are so few of them still around, even though they were made from 1985-2006. These issues causes catastrophic failures, and a lot of the bikes probably got scrapped at fairly low mileage. IMO, Kawasaki really messed up on what was otherwise a wonderful bike, just with a couple of stupid, easily fixed mistakes. And they never fixed these mistakes during the entire 21 year production run.