stock bore size and a shell #1

And so much for that calibration certificate! Off a full .001" on top ring thickness, and .0005" on the middle--those thicknesses should be .047" top, .059" middle. So I think we can be pretty sure that width (ring depth) should be 3 mm.(=.118"). Oil ring thickness given in the chart must be the minus the rails, the full stack was much thicker.
 
Interesting stuff, this thread is turning into the answers that I've wanted but haven't found. Hopefully it can help out other engine builders when it is finished
 
And so much for that calibration certificate! Off a full .001" on top ring thickness, and .0005" on the middle--those thicknesses should be .047" top, .059" middle..

I dunno, Griz. The published values may just be some desk-jockey's conversion of the nominal 1.2mm and 1.5mm dimensions. Are the grooves 1.2mm and 1.5mm, with rings ground undersized to get the clearances (making your measurements valid), or grooves cut larger, or both? It's like the 8mm callout for valve stems. The guides are reamed for 8mm, with the valve stems ground undersized to get the proper clearances (exhaust smaller than intake). I'm keeping your actual measurements in my files.

So I think we can be pretty sure that width (ring depth) should be 3 mm.(=.118")..

That's the important one that's missing from the charts.

Oil ring thickness given in the chart must be the minus the rails, the full stack was much thicker.

That one has me concerned. The 2.8mm (0.110") oil control ring is a constant dimension for all the models. Even my old 750 kit used 2.8mm.

Your measurement of 0.150" is close to 3.8mm, and oddball dimension. The closest/common oldschool/automotive dimension is 4.0mm (0.157").

More ring/land/groove trivia in this thread:

http://www.xs650.com/threads/need-help-with-piston-id.42027/
 
Re. width, my measurements were taken on used rings. I'm thinking 3 mm.(.118") is the better bet. Anybody out there with a set of new rings in the stash want to chime in here?
 
Good news on those carbs, only the pilot and main jet are off from you recipe griz. They have plastic float bowls which I find interesting. They are dirt and are being soaked as I type. 90 bucks shipped, I think I did pretty well, but we will see is any gremlins show up
 
Plastic float bowls on VM34's? That's a new one on me! BTW, what I gave you is a baseline to tune from, not a recipe. Anyway, what pilots and mains did you find?

2M, I measured the oil control ring parts separately, and got the same thing as when I measured the stack. Rails were .025" each, and the expander was .010". Same numbers on 3 sets of 447 rings.
 
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27.5 pilots and a 190 mains might come in handy later, those floats bowls are cool but i dont think i trust them. they look pretty beat up and dont sit flush with the mating surface. im going to invest in new bowls and ill test these floats tomorrow morning.
 
This is my oil cooler/remote filter blue print and i wanted to get a second set of eyes on it before i started drilling into the case. the red circle i where ill be tapping into the oil feed right after the pump. from there it will get pushed through a remote car style oil filter then through a cooler. the blue circle represents where ill plumb in the return of the cooled and filtered oil. the yellow lines represent areas i will block off. That is really what i want an opinion on, If i block those areas that would essentially mean i eliminated the bypass valve correct? But if i do not block it, would that have adverse effects on my fancy new oiling system plumbing i.e oil not getting filtered or cooled and just going straight into the main galley.
 

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