Oil ring question

seattle##gs

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I have an oil ring (for a Triumph) that is the usual shape for a one-piece ring. Behind it there is an odd thing that looks like it should be the expander. It is a thin wire with two ends - not a continuous loop. This wire has what appears to be a spring wrapped around it but I don't think it is a spring. I have been told that it's real function is to gather and hold oil...true? #2..the ring is almost impossible to fit in the bore as is and I have been told that the wire needs too be shortened because the wire ends butt into each other.....true? The oil scraper ring has very little pressure when fit into the bore without the wire thingee behind it. Though the oil ring does not require high pressure I think it should have more than this. I am reluctant to shorten the spring doo-hickey.
 
seattle##gs said:
I have an oil ring (for a Triumph) that is the usual shape for a one-piece ring. Behind it there is an odd thing that looks like it should be the expander. It is a thin wire with two ends - not a continuous loop. This wire has what appears to be a spring wrapped around it but I don't think it is a spring. I have been told that it's real function is to gather and hold oil...true? #2..the ring is almost impossible to fit in the bore as is and I have been told that the wire needs too be shortened because the wire ends butt into each other.....true? The oil scraper ring has very little pressure when fit into the bore without the wire thingee behind it. Though the oil ring does not require high pressure I think it should have more than this. I am reluctant to shorten the spring doo-hickey.
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That's a standard modern Hepolite oil ring. They look just like the originals but have that spring added. The wire is only about 3/4"-1" long and is there to hold the ends. When installed the spring increases the outward pressure. They are harder to get in but are supposed to be. There was a recent thread here where it was talked about a lot and people thought they should shorten the spring - NO! I posted a note from the manufacturer at that time. It has nothing to do with "gathering and hold" oil.
 
Here is the thread. Ignore the subject title. It is really about the evolution from the old Hastings supplied style of oil rings to what Hepolite sells now.
Controversial topic. Many folks don't like the new style, but your options are limited.

Hasting Oil Rings

I recently bought Hepolite pistons and rings for my Commando. I was told that the rings were made by Hastings, but I also have read that this isn't always the case. The oil control rings that came with the pistons seem wrong. They are a two piece style oil control ring, with a stiff inner...
www.accessnorton.com www.accessnorton.com
 
I built an 850 engine for a friend about eighteen months ago & encountered the same problem. With the oil ring & expander as supplied the piston was ludicrously tight in the bore. I shortened the spring expander 5mm / 0.196" & it was fine.
 
Matchless said:
I built an 850 engine for a friend about eighteen months ago & encountered the same problem. With the oil ring & expander as supplied the piston was ludicrously tight in the bore. I shortened the spring expander 5mm / 0.196" & it was fine.
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Hopefully you realize now that shortening it was the same as leaving it out. I'm sure it works, back in the 70s the Hepolite oil rings looked the same but had no spring. IMHO, it's a matter of trusting the manufacturer or not - If I did not, I would simply not use their product.

They go in very tight and quickly loosen a little. Then they are settled after a short period of running.
 
I was able to fit the cylinders after three tries and a lot of struggle. When turning over the motor by hand the right side started to leave a vertical groove so I stopped. I found a set of original rings with the one piece oil ring and will install them tonight. I'll stick with what I know works.
By the way, the original Triumph wrist pin has a tapered bore and is noticeably lighter.
 
marshg246 said:
Hopefully you realize now that shortening it was the same as leaving it out. I'm sure it works, back in the 70s the Hepolite oil rings looked the same but had no spring. IMHO, it's a matter of trusting the manufacturer or not - If I did not, I would simply not use their product.

They go in very tight and quickly loosen a little. Then they are settled after a short period of running.
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You might trust the manufacturer, but I trust forty plus years of building my own & other peoples engines. When a piston is so tight in the bore that it's difficult to move there is something wrong.
As for shortening the expander being the same as leaving it out altogether, the engine I built does not smoke.
 
Matchless said:
You might trust the manufacturer, but I trust forty plus years of building my own & other peoples engines. When a piston is so tight in the bore that it's difficult to move there is something wrong.
As for shortening the expander being the same as leaving it out altogether, the engine I built does not smoke.
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This has been discussed on here before
I have had to shorten expanders in the past without any issues
 
Maybe not directly comparable, but piston rings in modern car engines have very low radial pressure and negligable oil consumption.
 
Matchless said:
You might trust the manufacturer, but I trust forty plus years of building my own & other peoples engines. When a piston is so tight in the bore that it's difficult to move there is something wrong.
As for shortening the expander being the same as leaving it out altogether, the engine I built does not smoke.
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I never said it would smoke. In fact, I said a few times that the rings appear to be the same as they were in the 70s, except with the spring now. My point is taking 5mm off is the same as leaving the spring out. My 55 years of experience tells me that they will work without the springs, but my 0 years of scientific testing tells me either to trust those who have tested or not use their products!
 
Since Hastings is out of the picture for Norton and some don't like oil rings with springs what standard pistons and rings do you like for plain old road bikes.

seattle##gs: Hastings still makes Triumph and BSA rings.
 
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Greg wrote: "Hopefully you realize now that shortening it was the same as leaving it out."
I have to disagree with this comment. When I was installing the "new" style Hepolite pistons and rings I also shortened the internal expanding spring as I found it next to impossible to install and resulted in very high drag on the cylinder walls. By incrementally shortening the spring and refitting the piston each time, I was able to detect an incremental reduction in drag. The internal spring was still functioning but with less "preload" each time.

Greg did say in an earlier reply that the rings go in tight but loosen up in use. I might be able to partially answer this as I recently located some NOS Hastings rings and may swap them out for the dodgy Hepolites. Which by the way, seem to work ok, but leave me with higher oil consumption than I would have expected.
 
Stephen Hill said:
Greg did say in an earlier reply that the rings go in tight but loosen up in use. I might be able to partially answer this as I recently located some NOS Hastings rings and may swap them out for the dodgy Hepolites. Which by the way, seem to work ok, but leave me with higher oil consumption than I would have expected.
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Could that oil consumption be that you did not install the Hepolites with the correct spring length?

BTW, I've installed them in 750s and 850s with my fingers and have had no oil consumption or smoking problems. I never use ring compressors as I can no longer hold the cylinders and manipulate the pistons and most ring compressors are crap. Each piston is installed in its cylinder with the cylinders upside down up to the pin. Then the cylinders are lowered to the rod using my engine hoist. I didn't "invent" the method but am probably the first to use an engine hoist.

Start reading at Aug 20, 2023 here to see what I mean: https://www.gregmarsh.com/MC/Norton/HighMileage850.aspx
 
ludwig said:
Maybe not directly comparable, but piston rings in modern car engines have very low radial pressure and negligable oil consumption.
Click to expand...
This is true in most cases, & is done to cut down friction for better economy, but some Audi engines had serious problems with oil consumption, so bad in fact, that in the U.S. owners filed a group action against Audi to pay for replacement engines, as they were consuming oil at the rate of up to a quart per 200 miles.
 
I put the same rings in my triumph 68 daytona.I had never used them before so I went on the triumph forum to check them out.They do fit tight but seem ok at startup and after a few miles no problems. My commandos have never used those but they seem ok so far in the triumph.
 
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