roper plate revisited

[rocker59]

I have Roper Plates on both my Sport 1100 and my Nero Corsa.

 

No problems with installing either.

 

Great product !!!

[Guest NotRight]

After doing battle with this one for decades and getting nowhere, I finally concluded that the sound of a motor building enough RPMs to just start to approach (but not yet get into) the bottom of the powerband is irritating to feminine audio nerve sensitivities. It has to be be a certain harmonic range they can't tolerate. Men apparently can't hear this range of sound. It's like a dog whistle. However, the horriffic clattering, detonating, groaning, bucking lamentations of a motor upshifted to 2nd gear before halfway through an intersection when the light turns green at just above idle RPM, when the clutch is let out and throttle opened wide, is somehow quite satisfying to the feminine mystique. . .

 

Ratch: You're right...in a sense. My opinion was they (she) believed they (she) is hurting the engine because it is audible. Explanations of durability, redline, "ca--hunca cahunk" = not good were to no avail. We were still in 3rd gear by the end of the driveway. Maybe they just know its traumitizing to us and they do it because they........... nah. I love women and they wouldn't do anything sinister.

 

Like break up with you via text message.

 

 

Thread: Pete, this is a note to let you know that sometime this spring I'll be interested in a Roper Sheet so if the septic-tank supply is depleted I'll need one from you. At the moment I'm waiting for my tax refunds so I can't cut you a cheque just yet.

 

Thanks for making these. With that and a hose clamp I think I'll pretty much forget about paranoia of non-electrical problems.

 

I wonder: Have you ever suspected the breather system to be a cause of problems? It uses the box section spine to collect the oil. If it doesn't drain, say due to a stuck check valve, how many liters of oil can fill that thing?

 

MY GOD!! ITS the breather! ITs the breather thats killing us!!

[pete roper]

If there is a blockage in the return line/s then yes, you can fill up the frame. The problem with this hypothesis is that the return doesn't, or shouldn't have, any valves in it. The PCV valve is in the breather pipe from the crankcase, this is where the vapor and oil exits the case on the way to the spine. After the oil has condensed it simply runs down the spine and returns to the sump via gravity.

 

What DID tend to happen on older roundfins which also had the return below the level of oil in the sump was that after a period of extended running the earlier breather system where the condensor was a box about the size of a cigarette packet would be unable to cope and coupled with the fact that once the engine was taken above 900cc and cast iron bores, (In particular.) the case wouild pressurise and force oil back up the return until it flooded the breather box. First sign of this on SP's and the like was when the bike lost power and delivered a huge smoke screen as the oil flowed from the airbox, through the carbs and into the engine.

 

The V11's and earlier squarefins ALL use/d a crankcase with a larger volume, (This is including the sump, spacers etc.) which essentially cured this predilicion unles the oil level was run too high.

 

The reason why I don't think that expulsion through the breather is a major problem on the spines is a combination of the bigger case volume and reduction in windage due to the oil being further from the crank and that experience has shown that the starvation problem will occur during hard acceleration and not during extended high speed running. If it was an expulsion or non-return problem then it would be more likely to manifest itself during high speed running rather than hard launches. Well, that's my take.

 

I think that Greg's torture test after he installed one of my plates, (Sent for independent assesment, not just my word for it.) proves that whether my theory is correct the plate WILL offer a sollution to the problem. Is it the 'Best' or 'Only' sollution? No, of course not, but it's pretty cheap compared to any alternatives as well as being simple and ellegant.

 

Pete

[Ryland3210]

After the oil has condensed it simply runs down the spine and returns to the sump via gravity.

 

The reason why I don't think that expulsion through the breather is a major problem on the spines is a combination of the bigger case volume and reduction in windage due to the oil being further from the crank and that experience has shown that the starvation problem will occur during hard acceleration and not during extended high speed running. If it was an expulsion or non-return problem then it would be more likely to manifest itself during high speed running rather than hard launches. Well, that's my take.

 

I think that Greg's torture test after he installed one of my plates, (Sent for independent assesment, not just my word for it.) proves that whether my theory is correct the plate WILL offer a sollution to the problem. Is it the 'Best' or 'Only' sollution? No, of course not, but it's pretty cheap compared to any alternatives as well as being simple and ellegant.

 

Pete

 

Hi Pete,

 

Do you really think the oil reaches a high enough vapor pressure at the engine's operating temperature to evaporate and then condense, or is it unburnt fuel and water vapor mixed with oil particles suspended in the gases?

 

As my before and after test shows, your plate does the job with a 4 quart refill. Short of relocating the oil pickup, what other alternative is there? Darned if I can think of anything practical. Besides, doesn't the plate reduce windage as well, or is that insignificant without it?

 

Cheers, John

[Skeeve]

However, the horriffic clattering, detonating, groaning, bucking lamentations of a motor upshifted to 2nd gear before halfway through an intersection when the light turns green at just above idle RPM, when the clutch is let out and throttle opened wide, is somehow quite satisfying to the feminine mystique. . .

 

It's a power thing. They feel like they're "taming the beast" if it's bucking beneath them but still does what they want [in this case, continue to move forward.]

[Skeeve]

Do you really think the oil reaches a high enough vapor pressure at the engine's operating temperature to evaporate and then condense, or is it unburnt fuel and water vapor mixed with oil particles suspended in the gases?

 

The oil vapor isn't so much from heat/vapor pressure issues, as just plain "pumping" creating an aerosol: there's a lot of oil getting sprayed around inside an engine, esp. the bigger the cylinder - ie, large singles worse, twin of the same displacement less so, triples less, & on down the line. MG's 500cc V8 probably didn't have much oil entrainment to worry about, just pushing it all around the engine from one area to another... - this is an oversimplification, but it all comes down to air moving around inside the engine, picking up droplets of oil in the process, & then were is it all going to go so the oil can fall back out of the aerosol suspension?

 

At least, that's the way it was told to me...

[Ryland3210]

The oil vapor isn't so much from heat/vapor pressure issues, as just plain "pumping" creating an aerosol: there's a lot of oil getting sprayed around inside an engine, esp. the bigger the cylinder - ie, large singles worse, twin of the same displacement less so, triples less, & on down the line. MG's 500cc V8 probably didn't have much oil entrainment to worry about, just pushing it all around the engine from one area to another... - this is an oversimplification, but it all comes down to air moving around inside the engine, picking up droplets of oil in the process, & then were is it all going to go so the oil can fall back out of the aerosol suspension?

 

At least, that's the way it was told to me...

 

That makes sense to me. As you describe it, the oil is in suspension, rather than in the gas phase. I was thinking in terms of the engineering definition of "condensation", as the gas stage of a fluid going to the liquid phase as temperature drops below the saturation point. That's called the familiar "dew" point for water vapor.

[dlaing]

From http://www.bobistheoilguy.com/motoroil.html

FLASH POINT

Flash point is the temperature at which an oil gives off vapors that can be ignited with a flame held over the oil. The lower the flash point the greater tendency for the oil to suffer vaporization loss at high temperatures and to burn off on hot cylinder walls and pistons. The flash point can be an indicator of the quality of the base stock used. The higher the flash point the better. 400 F is the minimum to prevent possible high consumption.

And from Amsoil Propaganda

http://www.synthetic-motor-oil-change-and-...ct-code-amo.php

RESISTS HIGH TEMPERATURE VAPORIZATION

Conventional motor oils tend to "boil off" in high temperatures, losing up to 25 percent of their original weight. These vaporized oils circulate poorly, reduce fuel efficiency and contribute to excessive emissions and engine wear. AMSOIL High Performance Synthetic 10W-40 Motor Oil resists vaporization. In fact, according to the NOACK Volatility Test, which measures the weight loss of an oil due to evaporation, AMSOIL High Performance 10W-40 only loses 7.0 percent of its weight in high temperature service, surpassing rigorous European standards set at 13 percent weight loss in high temperature testing. The superior vaporization resistance of AMSOIL High Performance 10W-40 keeps engine wear, oil consumption and emissions to a minimum, while keeping oil circulation efficient and fuel economy high.

 

I would assume that almost all the vaporization occurs at the hot cylinder walls, not at the sump bath.

I wonder how much of oil loss is due to vaporization and how much is due to mechanically generated aerosol????

I guess it does not matter if you use a shloppage sheet as oil loss will be reduced.

[Guest ratchethack]

I would assume that almost all the vaporization occurs at the hot cylinder walls, not at the sump bath.

I wonder how much of oil loss is due to vaporization and how much is due to mechanically generated aerosol????

I guess it does not matter if you use a shloppage sheet as oil loss will be reduced.

Dave, at 6K RPM, the crank is whipping up Pete's favorite maelstrom of a crankcase-filling mass of aerated oil in great walloping streamers of aerated oil trailing off the crank webs, turning every available cubic millimeter of crankcase volume into a maniacal frenzy of aerated oil. This is where the air-oil suspension occurs, not on the cylinder walls. 6K RPM is 100 revolutions per second!!!! It's beyond mortal imagination to conceive how violent this is. Consider this to be oil poured directly into an ultra-ultra-high-speed air-oil blender. I reckon it's so hard to magine, that this is why Pete set up a "look see" total loss oil feed experiment with the sump off a Guzzi donk, and ran the motor with a tube-fed oil supply, sticking his head underneath to see wot it was like when he started it up and revved it, as he's been wont to relate upon appropriate occasion. It weren't a pretty thing to imagine, and I reckon the clean-up effort was considerable, but I'm pretty sure it was an effective demonstration nonetheless.

[dlaing]

This is where the air-oil suspension occurs, not on the cylinder walls.

Ratchet,

Yes, I agree that the aerosols are generated mechanically(largely by the motion of the crank). I only suggested vaporization occurs at the heat of the cylinder walls.

[Guest ratchethack]

Hm. D'you think that the latent heat of vaporization of engine oil, which is certainly technically a factor at the cylinder walls at operating temperatures, might be at all a quantitatively significant factor with regard to the consideration of windage, engine breathing, and condensation, to the point where it quantitatively has any effect wotsoever compared to direct heat transfer of cylinders to the oil bath, per the above discussion in the crankcase environment that Pete (and Yours Truly above) have described?

 

Just asking.

[Ryland3210]

Pete Roper's thorough checking of the oil path was a factor in his decisions on where to place the drainage holes in his plate. That extraordinary and messy example of due diligence sure built my confidence in his design.

 

Here is my contribution on this topic:

 

OK, here is a final report on refilling levels with Roper plate installed:

 

Test conditions:

Bike had not been started for one week.

Sump drained, filter removed, oil removed from filter access cover.

Bike left to drain overnight.

Installed new filter, and added 4 US quarts oil.

Restarted engine long enough to fill filter and build up oil pressure.

Bike supported to hold sump level using a good carpenter's spirit level.

All dipstick measurements taken screwed in using standard OEM dipstick, tip was 5.475" from its flange.

Measured oil level on dipstick: 0.88" beneath the Roper plate, 1.75 from the end of the dipstick.

18 additional oz. of oil were required to fill to 0.88 inches higher along the dipstick.

This works out to a relationship of approximately 0.049 inches per ounce.

Total oil to fill to Roper plate is therefore 4.32 liters, or 4 quarts-18 oz. US, or 3 quarts-25.6 oz. Imperial.

This includes the oil to fill an empty filter.

 

Cautions: :!: This is the level to just kiss the bottom of the plate on my bike. In operation, it will drop somewhat as oil circulates in the engine, which is normal. Refilling by this amount under different draining conditions may result in overfilling, so it is wise to check level with the dipstick after running the engine long enough to fill the filter and build pressure, and adjust if necessary before riding. You can use the 0.049 inches per ounce (about 20 ounces per inch) to estimate how much oil to add if low.

 

With the Roper plate installed and level sump, it takes a few minutes for the fresh oil to drain down through its holes, so wait until the oil is drained into the sump before measuring. If unsure, take at least two measurements. If different, wait a while and check again to get an accurate reading.

[pete roper]

Ryland, with the greatest of respect it DOESN'T have to be that precise. Really.

 

Put in plate. Mark stick just below plate, (Screwed in, screwed out? Doesn't matter.). Fill new filter with oil, install, with or without clamp . Replace sump. Fill with oil with bike roughly upright and to the new 'Full' mark. Go ride. Check oil occasionally That's it, end of story.

 

The quantity of oil to the nanno-poofteenth of a cc. is totally irrelevant. There has to be enough in there to do its job and the less space beneath the plate with air in it the more effective it will be in reducing rearward surge. That's all there is to it.

 

I feel the argument about what *is* vaporisation and condensation is simply an argument in semantics. The idea of the frame or box as 'Condensors' is the same as a septic tank 'Settling' pooh. Just that you're taking globules of oil rather tha turds and separating them. You can argue till you're blue in the tits about whether the oil changes state, on the cylinder walls or anywhere else, and whether it then re-forms into *oil* i the frame. The fact is it isn't, as far as any of us are concerned, important, because it won't have any effect that we can do anything about which we have any control.

 

Do we want to have a quick thread on piston rings and their functions? Do we want to examine the physics of heat in a combustion cycle? I'm more than happy to run through the basics, (Which is all I'm qualified to do.) if people want but seeing as nobody seemed to want to find out more about bearings I'm quite happy to leave it if it is deemed uninteresting or irrelevant.

 

Pete

[dlaing]

Hm. D'you think that the latent heat of vaporization of engine oil, which is certainly technically a factor at the cylinder walls at operating temperatures, might be at all a quantitatively significant factor with regard to the consideration of windage, engine breathing, and condensation, to the point where it quantitatively has any effect wotsoever compared to direct heat transfer of cylinders to the oil bath, per the above discussion in the crankcase environment that Pete (and Yours Truly above) have described?

 

Just asking.

Latent heat at cylinder walls compared to heat transfer to bath? What relevance would that have?

I was only pointing out that vaporization does occur, and I suggested that I did not know how it compared to oil in aerosol.

But since you asked, I will do my best to answer:

I'd guess that neither the latent heat of vaporization, nor the heat transfered to the oil bath have much effect on windage, engine breathing, and condensation. How the two compare? The heat of vaporization will directly result in vaporised oil that will increase windage slightly, condensation is probably already maxxed out, and engine breathing should be immeasurably effected.

While the heat transfered to the oil bath has no direct effect on windage, breathing or condensation. The direct effect is that the oil warms! The warmer the oil the lower the viscosity. I would guess that a lower viscosity might go into aerosol more easily and thus increase windage slightly, and engine breathing might be slightly effected as the warmer oil swells.

As I said, I don't understand the relevance of comparing the two.

Comparing Vaporization with Aerosolization (made up word) is much more relevant.

And even that difference is not very important.

If vaporization is a significant cause of oil loss, than using an oil with a higher flash point would help reduce oil loss.

[raz]

Ryland, with the greatest of respect it DOESN'T have to be that precise. Really.

I'm sure Ryland understands that, he just made an exact measurement once and for all and documented the conditions very well (ok it was anal but that is much better than establishing an incorrect figure). I appreciate it because this means I can use a 4 liter bottle without worrying about it.