Long upper engine mount bolt question: Yes, this topic came up when one of us lost the entire through-bolt recently. Amazingly, he drove back to where he heard a clang and found the darn thing in the street. Mine has seemed "loose" for as long as I've had the bike.
Well, I decided to take the through-bolt off and inspect more closely. The nut on the left side was tight (at least the 33 ft/lbs specified by Clymers). The through-bolt did spin, but with some effort. I shot some silicone spray lube into the surrounding areas, making sure to douse the rubber parts thoroughly (I understand it's good for the rubber anyways). I then took two long-handled ratchet wrenchs and loosened the nut. It was slightly corroded onto the bolt, but came off OK eventually. The through-bolt slipped out of the opposite side easily. There are two caps with rubber washer-like female inserts on either side. They insert onto a protruding rubber damper coming out of the motor mounts on the frame. These dampers flare out to fit into the motor mounts on the frame. They also cannot be removed unless the engine is pulled first. So, there doesn't appear to be any chance of them falling out. Identical on both sides. The right motor mount is a break-away mount held onto the frame via two 10 mm bolts, which I tightened (17.5 ft/lbs) just for good measure. What I noticed was that when the through-bolt is tightened, it does not tighten up against any of the rubber parts. There are metal sleeves in the rubber dampers, and those are what the bolt tightens up against. The rubber is purely for isolation. The gap that we are seeing appears to be the rubber shrinking. It does get very hot in that area. You cannot tighten the nut to pull the rubber pieces closer together. Won't work. I silicone sprayed all the rubber, applied some blue loctite, and put everything back together. I'm confident nothing is wrong, just some shrinkage of the rubber. Newer VN750s don't have the gap ( yet). But older ones I've seen have it there (mine is a 1995). If anyone wants to see some photos of my rubber dampers, let me know. --
Yesterday I received the motor mount parts that I ordered and started to install them. Missing are the two spacers that go between the dampers and the boss cast onto the rear exhaust manifold. I had ''ass u me d'' that they would be included as part of the inner dampers. Well [email protected]
%&*()! of course they are not, and I discovered that they are called ''insulators'' and on shown on the cylinder head fiche. So, another ordered placed and another week of riding with my jury rigged rear motor mount.