I fixed it.....the wet sumping that is. (2014)

Wow, I used to have a good memory... A picture is hard to argue with for sure. Obviously, I'm wrong about that. It's been a long time since I had the big ends apart, and my memory failed on that detail. I'm glad you straightened me out. It's not useful to the group to have false info in the forum. I need to be more careful...

My commando actually had big end shells with no weep holes, when I rebuilt the bottom end. I thought this was a mistake of the last rebuilder, but someone here, who's opinion I respect quite a bit, told me that it was probably done by choice because the weep hole isn't necessary and maybe it helps with the oil pressure to the shells a bit.

I plan to fit 4 plain shells to that crank, if you look at the rod laying on the top you see low depth but wide slots machined in the side of the big end at the top of the big end, these are to direct the oil coming out of the journal upwards to take the place of the oil spurt hole. The big end eye still fully supports the shells as the rod width is greater than the shell.

The spurt hole is worthless. You won't find any difference without it. Thousands of Nortons with Carrillo rods and no spurt holes have been running all over the world and nothing ever happens. Oil flies out from the sides of the journals anyway and splashes off the bottoms of the pistons.

jseng1 said:

The spurt hole is worthless. You won't find any difference without it. Thousands of Nortons with Carrillo rods and no spurt holes have been running all over the world and nothing ever happens. Oil flies out from the sides of the journals anyway and splashes off the bottoms of the pistons.

Click to expand...

the proof of the spurting is in the heating, or lack of, one could say....

jan nelder said:

the proof of the spurting is in the heating, or lack of, one could say....

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Yes you can have more or less oil splashing around in the sump. You can even go so far as adding oil line fed oil squirters that help cool the under crowns of the pistons (as used on turbocharged motors). But there's no point if the pistons aren't overheating/melting. And overheating/melting of Norton pistons happens when the fuel mixture is too lean. I don't see any point in squirters for a Norton. As long as you have adequate oil lubing all the moving parts - any extra oil in the sump just causes more friction and robs power.

If you really want your motor to run cooler - then the best thing to do is go to alum cylinders (if you can find them now). I was fortunate enough to buy a set when Steve Maney was still making them.