W2000 welded rotor vs bolted rotor?

[FloridaMike]

I notice in another W2000 related post that "the sometimes problematic welded rotor has been changed to the bolted rotor".Anyone have some background on this? Was the welded rotor used in earlier models and the bolted rotor in later ones, or was there a running change so that all the later models (after date X or serial # X) have the bolted rotor?More specifically, since my W2000 is an autolube model (late), is it likely to have to bolted rotor, or is this entire thing much ado about very little or even nothing?(And are we even talking about the rotor in the engine, and not the brake disc rotor?)With best regards from rainy Florida,Mike

[kanonkopdrinker]

Hello MikeI don't know from which F&S engine number the change was made, but it refers to the ring which holds in the central bearing running surface .... the blob of weld which held the early ones in-situ was found often to be not up to the job; a change to three bolts cured all this.Given time, I could probably come up with the two part numbers for both types of rotor.David

[Joe]

Hello Mike, When I bought my W2000 injection model back in January 2004 from an ROC member the engine had been completly stripped due to a broken weld on the rotor. The break had damaged the end plate which Graham was able rescue but the rotor housing required replacement. Graham rebuilt the engine, and a fantastic job too and I rebiult the bike using stainless steel everywhere and I love the bike it's a pleasure to ride. When I learn how to, I'll post a photo of the damage.Regards, Joe.

[FloridaMike]

Question - obviously the early bikes had the welded rotor. Did series production change to the bolted rotor (and if so, at about what year/serial number) or was the welded rotor used to the end?I'm wondering if I could use a borescope to look inside without taking the engine apart . . . I don't think so . . .Any ideas on how I can determine if I have a bolted or welded rotor other than "It blew up, you used to have a welded rotor!"If I have a welded rotor, where to I get the bolted rotor or can mine be modified?Or is this not really worth worrying about (i.e. how often do they fail?).Best Regards,MikeinFlorida

[FloridaMike]

Answer provided by Hans (in this group). He replied directly to me and sent photos.Frame #s 1,000 and lower are definitely at risk. The outer race (sleeve) is tack welded to the rotor and after enough heating/cooling cycles, the welds break and scatter bits of metal in the engine. The sleeve moves in the rotor as well, which helps make a mess of everything. Problem is the difference in coefficient of expansion between the two parts. The harder the bike has been run, the sooner the failure can be expected. Opinion: If my bike had a frame number of 1,000 or less, I'd put this on my "to do" list NOW with a star indicating it is urgent. I'd probably also park the bike until it was done or I had verified that it HAD been done, either by paper trail or (better) by physical inspection of the rotor.Frame numbers 1000 to 1300 are the transition between the welded rotor and the bolted rotor. Being a cautious person, if mine were in this serial number group, it would probably be worth taking the end plate off the engine to take a look. You'll need some gaskets and about six hands to hold all the springs, edge seals and tip seals into place as you re-assemble the engine (ask me how I know this).After (about) frame 1300, the sleeves were locked to the rotors by Allen head setscrews, one side in the sleeve and the other side in the rotor, and then gently tapped with a center punch at two places to displace a bit of metal to lock them in place. The serial number on my bike is 5XXX, so I'm OK (whew).There is someone in Germany (Hans didn't say who) fixing the rotors. The cost is about 100 Euros. I don't know if he can fix one that has already broken, but it might be worth asking. A hundred Euros is cheap insurance against blowing up the engine, the tow home will cost more than that.Again, thank you Hans for a clear and precise answer to this question, and for the excellent photos!Best Regards,FloridaMike

[FloridaMike]

Here are the last two pix - this is a fixed (setscrewed) rotor. phpBB won't let me send more than three attachments per message.