Can you help me with the orientation of piston rings that came with no instructions

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DennisMo

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No instructions came with the rings for my Comando 850 Hepolite pistons.
Photos of the rings are below
1) Top ring looks beveled both sides (first photo) and has an oval stamp on it (second photo) but does not have a top marking on it.
Can it be installed either way up?
2) Second ring has "top" marking and an oval stamp (second photo).
This is clarity!
3) The Oil control ring is two pieces: The rail plus the spring (third photo). There is no top mark on it and the spring has an internal
guide piece (fourth photo). I guess it can be installed either side up.
In addition, the split in the spring of oil control ring came positioned 180 degrees from the oil control ring gap.

The Norton manual says the following: the top ring should be at the front side of the engine, the back ring at the back side of engine and the oil control instructions are for
a multi piece oil control ring with centre plus two rails so does not apply to this oil control ring

I would really appreciate your advice on what sides of the rings should be up and where to place the ring gaps relative to engine front

There were no size of ring gap specs with the rings so I thought to follow the manual (top ring gap of .010" to .012")
(middle ring gap of .008" to .012") if any are too narrow

Many thanks as always
Dennis

Can you help me with the orientation of piston rings that came with no instructions
Can you help me with the orientation of piston rings that came with no instructions
Can you help me with the orientation of piston rings that came with no instructions
Can you help me with the orientation of piston rings that came with no instructions
Can you help me with the orientation of piston rings that came with no instructions
 
The marks will always face the top or nearest the cylinder head. The oil control ring can be installed either way but if there's an marking at all I position them up. Stagger the gaps however you like just as long as they're not lined up. Rings do move around.
 
DennisMo said:
No instructions came with the rings for my Comando 850 Hepolite pistons.
Photos of the rings are below
1) Top ring looks beveled both sides (first photo) and has an oval stamp on it (second photo) but does not have a top marking on it.
Can it be installed either way up?
2) Second ring has "top" marking and an oval stamp (second photo).
This is clarity!
3) The Oil control ring is two pieces: The rail plus the spring (third photo). There is no top mark on it and the spring has an internal
guide piece (fourth photo). I guess it can be installed either side up.
In addition, the split in the spring of oil control ring came positioned 180 degrees from the oil control ring gap.

The Norton manual says the following: the top ring should be at the front side of the engine, the back ring at the back side of engine and the oil control instructions are for
a multi piece oil control ring with centre plus two rails so does not apply to this oil control ring

I would really appreciate your advice on what sides of the rings should be up and where to place the ring gaps relative to engine front

There were no size of ring gap specs with the rings so I thought to follow the manual (top ring gap of .010" to .012")
(middle ring gap of .008" to .012") if any are too narrow

Many thanks as always
Dennis

View attachment 123623View attachment 123624View attachment 123625View attachment 123626View attachment 123627
Click to expand...
Top ring oval up. Middle ring "top" up. Oil ring either side up. Gap in oil ring spring opposite gap in ring. Do not shorten the spring - they are hard to install and are supposed to be.

Ring gaps 120 degrees apart. I don't like on facing forward or back as it make it harder to install with the cutout in the cylinder skirt.
 
I asked this same question here last summer when I installed new hepolite pistons and rings. I am not an expert. A kind member gave a photo of the original instructions sheet. Probably still on the site here. I bought 0.10 oversize hepolite rings.
The new specs I believe are 0.20 ring gap. Original was 0.12. I chose 0.16 and used my ring gap tool. Spaced them at thirds. I may have just gotten lucky, but was careful. I have smoke free starts and running. I don't use any oil at all. My cylinders are stock. I just ran a bead hone. Compression was 95psi for the 1st 100 miles. At 120 psi now after 500 miles. So fun to ride.
So far so good.
 
robertv said:
I asked this same question here last summer when I installed new hepolite pistons and rings. I am not an expert. A kind member gave a photo of the original instructions sheet. Probably still on the site here. I bought 0.10 oversize hepolite rings.
The new specs I believe are 0.20 ring gap. Original was 0.12. I chose 0.16 and used my ring gap tool. Spaced them at thirds. I may have just gotten lucky, but was careful. I have smoke free starts and running. I don't use any oil at all. My cylinders are stock. I just ran a bead hone. Compression was 95psi for the 1st 100 miles. At 120 psi now after 500 miles. So fun to ride.
So far so good.
Click to expand...
.10
.20
.16

Inches?
Millimeters?

Not to pick nits, but we all learned measure and decimals in elementary school.
We learned that decimal placement matters.
We learned that it is ok to drop the preceeding zero.... but after the decimal, it matters... A LOT.

Hundreds of people will read your post, for decades to come.
 
"
Not to pick nits, but we all learned measure and decimals in elementary school.
We learned that decimal placement matters.
We learned that it is ok to drop the preceeding zero.... but after the decimal, it matters... A LOT. "


Yeah... if it's inches there is a missing "0" at the first position to the right of the decimal point! ;) IOW, a reasonable ring gap would be .016" NOT .16" The post should be edited to clarify/correct the measurements. The measurements as shown are not workable in either metric or imperial.
 
robertv said:
I asked this same question here last summer when I installed new hepolite pistons and rings. I am not an expert. A kind member gave a photo of the original instructions sheet. Probably still on the site here. I bought 0.10 oversize hepolite rings.
The new specs I believe are 0.20 ring gap. Original was 0.12. I chose 0.16 and used my ring gap tool. Spaced them at thirds. I may have just gotten lucky, but was careful. I have smoke free starts and running. I don't use any oil at all. My cylinders are stock. I just ran a bead hone. Compression was 95psi for the 1st 100 miles. At 120 psi now after 500 miles. So fun to ride.
So far so good.
Click to expand...
That is awfully low, are you doing the test with a warm engine and the throttle wide open? A Commando usually has 150 to 170 PSI after about 5 kicks that are firm and fast. I usually use the term : 12 thou to mean .012" Inch. I don't do metric very well.
 
"I don't do metric very well."

Yep! If imperial is good enough for the fine folks in Liberia and Myanmar, it's good enough for me!! ;)
 
I just measured the ring gaps

Top Ring left 9 thou right 9 thou

Second ring left 12 thou right 13 thou

Oil Ring left 12 thou right 11 thou
 
I'm assuming you had the cylinders bored and specified a .004" skirt clearance.

Generally the rings that come with Hepolite pistons have the same gap in both bores and are a little larger than the book value. Measure the ring gap 1" down from the top and use the piston to be sure they are even. Then do the same 1" up from the bottom. The gaps must be the same if freshly bored and honed.

If so:

The top ring gap should be .010"-.012" - carefully open it with a fine file and be sure to keep it on the same plane as the other side of the gap (in other words, squeeze them together and make sure they meet perfectly).

The middle and oil ring gaps are fine.
 
I pushed the rings down about 1 1/2 inches with the piston head to seat them evenly.
I will clean the bores with brake clean and clean the outside of the top rings and remeasure. I wouldn't be surprised it I measure 10 thou this time!!

Thanks Greg
Dennis
 
robertv said:
I asked this same question here last summer when I installed new hepolite pistons and rings. I am not an expert. A kind member gave a photo of the original instructions sheet. Probably still on the site here. I bought 0.10 oversize hepolite rings.
The new specs I believe are 0.20 ring gap. Original was 0.12. I chose 0.16 and used my ring gap tool. Spaced them at thirds. I may have just gotten lucky, but was careful. I have smoke free starts and running. I don't use any oil at all. My cylinders are stock. I just ran a bead hone. Compression was 95psi for the 1st 100 miles. At 120 psi now after 500 miles. So fun to ride.
So far so good.
Click to expand...
My mistake here. .016 is the gap I used. I apologize profusely for this critical mistake. I will say 40 hail Marys later and hope I have not caused the destruction of any ones' engine. A feeler gauge is a dangerous thing.
 
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