welded crank

Remember the Z1/KZ900/KZ1000 cranks are roller bearing cranks - the rollers stop rolling and start sliding once you get to around 10,000 rpm. At which point the bearing get hot, wear quickly, and will deteriorate rapidly if sustained high rpms are used.

i didnt know that;) is it some sort of centrifical force that throws the bearings against outer race where they cant spin?:blink:

stick with us kiddo well lean ya somethin :whistle: :woohoo: :woohoo: :evil:

Jeff.Saunders wrote:

Remember the Z1/KZ900/KZ1000 cranks are roller bearing cranks - the rollers stop rolling and start sliding once you get to around 10,000 rpm. At which point the bearing get hot, wear quickly, and will deteriorate rapidly if sustained high rpms are used.

Help me out with this (possible) urban legend of engineering then Jeff- IIRC, I was told that the reason they went away from the roller bearing type was because at around 200hp plus, the bearings start to fail (that figure is all over the place) and that is why the GS1100 was the superior drag motor when it came out- because it could take more than 300 hp?

Because, of course, the great advantage to the roller bearing type is the fact that you don't need much oil pressure.

mkII cranks can handle well over 200 hp with very little work.16v head made suzuki 1100 what it is,but early suzuki cranks sucked

Welding the crank will not make it rev higher. Good valve springs would.

The reason the cranks are welded is to keep them from twisting out of index, usually on the launch when you have good traction. If you rev it up and dump the clutch with a good tire such as a slick, etc. The traction will try for a moment to stop the crank. The load from the crank going to the clutch is over on one side. Therefore one end of the crank is trying to stop while the rest is trying to turn.

Jay