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Favorite piston ring spacing

ballbearian

Veteran Member
Joined
Nov 22, 2021
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Location
Hagerstown MD USA
120 degrees apart or 4 hours (clock face). Any preferred pattern ideas?
I've got these at 11 o'clock for top ring, 7 for middle ring and 3 for the oil ring for starters.
I noticed that the open ends of rings seemed to be thinner on the motors I disassembled, so thinking to put them near the outside because it is maybe a bit cooler?
This is a sloper style motor, a 160, if it matters at all.

mZnCuqB.jpg
 
I've always avoided having a ring gap in the thrust face area of the cylinder, and the gaps in the 3 piece oil rings are less critical than the old school 1 piece version.

ringgaps.png
 
180 degrees apart for each ring as you put them on, so odds and evens line up, but the gas has to go a full 90degrees around in either path.

There is absolutely zero science or experience to this - it just makes me feel good.

Pretty sure they rotate around once they’re in motion, so it doesn’t really matter too much - I just wouldn’t align them all… anything else seems to work well.


-Ed
1972 CL350
1985 VF700F
 
I approve, but I don't know diddly squat and didn't pay much attention to mine when I had mine apart. My thought is they MUST move around in use, but perhaps not. Next time I take my top end apart I think I will get some new rings and do that honing thing, as my cylinders were all shiny clean looking, which I thought must be good, but I guess not, that you want some patterns to allow the oil to stick to the cylinder walls is what I thought I learned. Maybe some new rings and honing will give my cylinders new life ;)
 
Thanks guys. I like the thrust face caution (that would be to the front only?). I've heard more 120 degree than 180 strategies, though both have some distance between gaps, which seems good. I'd love to hear LDR, 66Sprint and Jensen's take also.
These are stock Honda rings with one piece oils. Not sure 6 o'clock is cool for oil or any. Maybe swap top to 3 o'clock and oil to 11.
I like to feel good too but dudes in lab coats can't compare to greasy veteran wrenches.
 
I approve, but I don't know diddly squat and didn't pay much attention to mine when I had mine apart. My thought is they MUST move around in use, but perhaps not. Next time I take my top end apart I think I will get some new rings and do that honing thing, as my cylinders were all shiny clean looking, which I thought must be good, but I guess not, that you want some patterns to allow the oil to stick to the cylinder walls is what I thought I learned. Maybe some new rings and honing will give my cylinders new life ;)

I've done that top only/decarbon thing and got lucky on my 150. If you have good compression, don't mess with a beautiful thing.
 
Hard to argue with ancientdad as that's the way I orient them as well.....
Theoretically, this method leaves no gap either forward (shown as Top) or rearward (as the oil ring rails seal across the opening in the expander ring) .......
 
Hard to argue with ancientdad as that's the way I orient them as well.....
Theoretically, this method leaves no gap either forward (shown as Top) or rearward (as the oil ring rails seal across the opening in the expander ring) .......

Thanks, I thought the rear should be avoided too.

How about with a stock oil ring? 3/7/11 Ok?
 
Unless the rings are pinned they will move in either direction and while it will make you feel good and yes I do it too, after a few revs they will be dancing in circles. Higher revs means more movement.

I posted a technical article about it .... maybe on HT site.
 
Good points and information in this thread.
I place the gaps of the oil rings 180 degrees apart with the expander at 90 degrees from either one of them, doesn't matter which side the expander split is at since it's not sealing anything. The oil rings are set at 2 and 8 positions.
Top ring is set at 4 and middle at 10, again 180 degrees apart.
There's 2 thrust faces on the pistons, primary being the power stroke side and secondary on the compression stroke side.
One thing missing from this discussion is the ring land or groove. It's missed by many people. There's a condition known as ring flutter where the rings literally are oscillating vertically during any given stroke. This is where the measurement of the ring to piston gap at the top, or bottom, is measured. 99% of the time it's good on new pistons and rings, @70% on used pistons and new rings. If that gap is too large then the flutter will end up braking the rings.
I check that gap and also, using an old broken ring, drag the end lightly around the entire land feeling for ang snags or resistance. If there's anything felt that means there's a burr that will keep the rings from rotating like they should.
It's funny that the closer to horizontal the cylinders are the issue of rings lining up becomes more of a problem. BMW boxer engines suffered it for a long time until they pinned the rings but that created another issue of excessive wear due to no rotation. They solved that by using chrome rings and using Nikasil coating on the liners. I don't know how Honda dealt with this on the Goldwings.
 
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