Husky SMR450 bottom end issues?

[MotoRad-ical]

Howdy, try running a 10w60 oil like elf or plutoline, and change it every 100 ks, Plutoline @ $20 L and elf @ $34 L it's a hell of a lot cheeper than bearings. I'm picking with the hi comp setup and long straights at WOT are a big part of it. My SXV550 runs plain big ends and mains and fully relies on a film of oil at 80psi to keep metal components apart.
How long are you going between oil changes? At the top end of the engines stress you want an oil that can handle the sheer preasure and if your running a 40w it will not take the hammering your asking of it a 60w will hold up a lot better, And change it all the time. Cheers

Im running a 10w 60 fully synthetic Egip and replacing it and oil filter after every race meeting so I'm guessing its not that I was actually considering a thicker oil assuming its too thin but maybe not.

Oh to have a camera in there and see what the hell is happening.

[MotoRad-ical]

I had a good chat with a very experienced race bike mechanic about a gearbox issue I'd had with my 510. He said without a doubt run a thicker engine oil in these bikes, a 5w-50 or 10w-50. He said the 10w-40's are great for the road bike engines but too thin for the tards.

This was relating to a gearbox issue, but might apply to your bearings too.

Yea the mystery is whether or not the thicker oil will help or not. The Manual says run a 10w 60 fully synthetic which is like water but its what they spec.

[The Pink Panther]

you talked about the bottom end it was hardness tested and it came back fine. who tested that ? the casing's ! regards to flex if you had multiple failures from the bottom end.
the casing's you have , may have been over stressed and been with high poros ... gas porosity, shrinkage defects, mold material defects, pouring metal defects, and metallurgical defects.
Did husky helium test the casing's i dont think so, why ... it cost far too much to do so. every casing that is poured has a heat number , every sand mould is different you get a good one you get a bad one.
when i strip a motor i look at machining how well it was poured /jigs fixtures used to machine and in what process was taken to machine carnt help it its my job.
IE a top fueled drag car donk is billet CNC machined oh the sex and work load to make one hence the cost ... its a billet it is controlled from A to B and C.

[MotoRad-ical]

you talked about the bottom end it was hardness tested and it came back fine. who tested that ? the casing's ! regards to flex if you had multiple failures from the bottom end.
the casing's you have , may have been over stressed and been with high poros ... gas porosity, shrinkage defects, mold material defects, pouring metal defects, and metallurgical defects.
Did husky helium test the casing's i dont think so, why ... it cost far too much to do so. every casing that is poured has a heat number , every sand mould is different you get a good one you get a bad one.
when i strip a motor i look at machining how well it was poured /jigs fixtures used to machine and in what process was taken to machine carnt help it its my job.
IE a top fueled drag car donk is billet CNC machined oh the sex and work load to make one hence the cost ... its a billet it is controlled from A to B and C.

I'm not sure who tested the pin last time as it was prior to my ownership however it was done through an engine reconditioner who I have since delt with and found him competent and througher.

I know what you mean by poor casting, porosity, slag inclusions etc and it could possibly be something to do with that in saying that the castings are clean and well machined (perhaps not helium tested) if I was to compare the internals of this motor to a jap bike like a CRF450 parts that are cast in a jap bike have been fully machined out of solid alimunium in this. If there was a misalignment in a machining prosess caused by anything it should hopefully be picked up in assembly in saying that something slightly out of square might not however the cost of this to replace both casings would be horendious I also no longer have access to a CMM (Coordinate measuring machine) or CMM table to measure off. I guess it gets to a point where you have to rely on the quality checks.