My CVs have a couple of thousand hours on them over the last 5 years. I anticipate them lasting longer than the engine. Maintenance involves checking the bolts and pushing on the rubber sleeve to make sure there is enough grease in the joint and then filling if necessary. When bolts are torqued with loctite, I would imagine you could get by without adding grease for 1000 hours+. Now I'm only running them at about 500-600 RPMs and rarely much faster. I carry 2 spare joints. But have not needed them. They are splined so they just slip over the shaft.(I was a little concerned myself about one of them coming apart and having a 4' shaft rotating wildly through the engine room at 500 RPMs. I built these big steel tube brackets that I mounted around each CV to contain any failures. Probably overkill, but for a couple of hundred bucks...) The other benefit of the CV that we haven't talked about, is that they compensate for SLIGHT shaft misalignment and reduce vibration. With the thrust bearing, they take the stress off the engine and keep the engine vibration on the engine mounts. The CV also allows you to have a prop shaft that is parallel to the waterline so that all of your thrust is going in the proper direction. Mike > Message: 2 > Date: Sun, 7 Feb 2010 17:16:42 EST > From: SeaLubber7@aol.com > To: power-catamaran@lists.samurai.com > Subject: Re: [PCW] Thrust Bearing > Message-ID: <d330.7fec944f.38a095ca@aol.com> > Content-Type: text/plain; charset="us-ascii" > > Mike, do the cv joints require a lot of maintenance? What is their life > expectancy? Do you carry spares? Thanks, Ed Schwein > > > ------------------------------ > > _______________________________________________ > Power-Catamaran Mailing List > > End of Power-Catamaran Digest, Vol 58, Issue 6 > **********************************************