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Pete Roper's Plate Function and Design Intent


Thunderpaugh

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Pete Roper. I've read most all the threads about the Roper Plate. Tell me if the following is true. The plate is a windage tray that allows the sump to be filled with oil to a level higher than manfuacturer's specifications to prevent the oil pick-up tube from being exposed during hard acceleration, wheelies, (and maybe steep hills that Pierre thinks would require knobbies, or as you suggested, steep hills with a turn to the left while under acceleration), which tray prevents the overfill from being discharged through the crankcase breather, and maybe into the air filter. No doubt that it works, just trying to sort out the logic and design intent behind it. Anybody else have an opinion?

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Guest ratchethack

TP, the man's not only been kind enough to produce this thing and ship it all around the globe for a pittance relative to the time he's got in it -- often advance shipping the things! He's probably losing money on it! -- but he's likely spent more time here and on other Forums having to explain, re-explain, & re-re-explain it's purpose ad nauseum, as well as defend himself against attacks of charlatanism to those who haven't got a clue wot they're complaining about. . . <_<

 

He's already described it in detail several different ways here, which you can find with searches that you evidently haven't discovered. I would urge you to keep looking, I can't do his descriptions justice.

 

He takes great pains to SEPARATE his plate from a windage plate by calling it a "sloppage" plate, since it serves an entirely different, though possibly slightly related (and largely unintentional) function.

 

Yes, it has the effect of reducing the kinds of oil loss that could otherwise occur due to windage by overwhelming the oil condensor and puking into the airbox.

 

It works as designed as far as I'm concerned, and no I'm not indulging in wishful thinking or justifications for time and effort already spent. I'm coming up on 2 years now (I think that's right?) with mine. ;)

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Hi, Pete's plate is more properly a "sloppage tray". When you accellerate hard, or go up a grade, forward movement and gravity causes the oil to go to the back of the crankcase AND UP the back wall of the crankcase too. Imagine a glass of water, suddenly slid forward, hard. Or tipping that same glass and holding it at an angle. As the oil moves back, the level in the front of the crankcase goes down, sometimes enough to let your oil pick up suck a good gulp of nothing but air. With the plate, the oil has a "ceiling" that contains the total oil volume to a smaller overall room. It limits the slopping of the oil to the bottom of the crankcase. In in my case,I would see the red light on plenty of brisk take offs. Put in a sloppage plate, and have not seen the red light ONCE while running, including lifting the front wheel in 2 gears. It works, NO DOUBT.

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Baldwinstreet.jpg

Even with a sloppage sheet, accelerating quickly up a lengthy hill like this could cause oil starvation because the oil slowly drains rear and upward.

Without a sloppage sheet even a short hill can do damage.

Riding wheelies, the longer the front is in the air, the more likely you will have oil starvation.

Pete's solution is simple and it protects in most situations that would otherwise have oil starvation.

Pete sent me a piece of sheet metal he used as a prototype.

Since it is over-worked, Pete had no use for it, but I am going to mount it about a cm lower than Pete's design.

I theorize that lower is better, at least at lower oil levels.

Also, I won't have to remove the sump or plumbing to install it.

But the only way to beat Pete's design is seal it tighter but then add one way drain valves, assuming you could find any that worked well and reliably.

I already over-worked it, so it will probably leak just a little more than Pete's design.

Man, it is a pain to get it to fit.

Once I finish fitting it, I'll try to remember to photograph it.

Pete must have spent hours getting it just right!

Pete's pre-cuts alone have saved me hours.

I think I have spent about 4 hours on it, and it is still far from finished.

With heavy sheet metal fabrication equipment and or know-how, it could be done faster.

In retrospect I should have spent more time getting the template right, or better yet, I should have just bought a finished one from Pete.

Unless you never use more than 75% throttle and never go up steep hills, do yourself and your engine a favor and buy a sloppage sheet from Pete.

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Dave, remember that the prototype is mild steel. While it will be prone to warpage there is nothing to stop you welding baffles and other such stuff on it if you wish. I simply didn't think that for any *normal* usage that would be neccessary.

 

As for the *Ideal* height of the plate? I have no idea! Perhaps there is some magic formula that allows people a lot cleverer than me to work it out, (My guess would be that this would be based on some swept volume to crankcase volume ratio.) but I work on previous experience of what has worked and hasn't in the past and I KNOW that running the oil higher than the bottom of the block, even on smaller capacity engines, is a recipe for disaster.

 

I also know of not one single case of a motor being fitted with one of my plates having blown seals due to excess pressurisation of the case or filling their air-boxes due to excessive oil expulsion, no matter how hard they are used.

 

I have not a shred of doubt that someone with much more money, time and interest could design something more technically perfect than my plate. I also believe that for the vast majority of normal human beings riding their bikes *normally*, (And by this I mean caning the freckle off them! :D ) on the public road my sollution is all they are ever likely to need to save their big ends/crank.

 

I have NEVER put pressure on anyone to buy my plate. Yes, I publicise it because I think it is a worthwhile addition to a flawed factory design but many, many people never have problems without one. I've supplied free samples to people I respect and admire as having knowledge of the Guzzi motor for the simple reason that I believe in results proven by independent examination and empiracle analysis. I'm NOT a believer that your fucking V11 will run better if you align its sodding 'Chakras' or sing the 'Ommmmm!!!' song to it for long enough.

 

Most of the people who spend so much time trying, usually without cause, success or reason, to denigrate my work have owned one or two Moto Guzzis. Many of them have experience of precisely ONE! Theirs! I'm not a fucking oracle. I make no claim to being either a magician or even a spectacularly good mechanic. I DO though have 30 years of experience of working on Guzzi twins in both a lay and proffesional situation and have probably worked on as many if not more V11's than anyone on this board with the exception of Greg and a couple of other posters who I suspect of being proffesional wrenches who just preffer to keep quiet about it.

 

One final thing. I don't have to gouge people or trick them into buying crappy products of no worth. Why? Because I'm more than rich enough not to have to. No, I didn't win the Lotto. Jude and I worked our arses off for the last 25 years and you know what? It paid off. We could retire tomorrow an live very comfortably thank you! So if you want to criticize my product at least do me the favor of doing it with some sort of scientific or engineering analysis rather than just sniping from the sidelines and making accusations of skulduggery 'cos quite simply I can't be pissed nough to care. :vomit::moon:

 

Sorry Dave, that little rant WASN'T aimed at you, re-reading it it looks like it might be read that way. sometimes even the bunny gets sick of being the bunny though....

 

Pete

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I think Pete should just design a simple bolt-on to relocate the pick-up! :luigi:

 

If you move the pick-up back, then every time you nail the brakes it would suck air, and let's face it- these things will brake a lot harder than they will accelerate. I have never seen the light flicker on my Tenni, but then again I took it easy on her after reading of the problem here until I had my Roper plate installed.

 

It's cheaper than a set of bearings, and easier to install.

 

Garsdad

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Guest ratchethack

A clever Engineer/Fabricator could whip up a movable sump pickup that would shift its pickup point fore-aft with the oil according to acceleration forces from both propulsion and braking. But o' course, any time you add such complexity to anything so vitally important, the risks simply get transferred to another place -- possibly multiplying in the process. <_<

 

-- and waddayagonna do?

 

post-1212-1210607584.jpg

ANSWER: Stick in a Roper slopper. ;)

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No doubt that it works, just trying to sort out the logic and design intent behind it. Anybody else have an opinion?

 

It's a baffle that keeps the oil from sloshing around inside the engine.

 

Windage trays are popular with people who race cars. Some older American V8s suffered the same problem under hard accelleration.

 

The hotrodders came up with two fixes. 1) a windage tray. 2). a second pickup in the oil pan.

 

It's simple, really.

 

I have the Roper/Moto Moda sheets on both my bikes and a third on the shelf for future use.

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Dave, remember that the prototype is mild steel. While it will be prone to warpage there is nothing to stop you welding baffles and other such stuff on it if you wish. I simply didn't think that for any *normal* usage that would be neccessary.

I don't ride wheelies, and I don't live in San Francisco, so no need for baffles and one way valves...

Between the windage effect letting me raise the oil level, and the anti-sloppage effect, I will be good to go, and much better off than I was.

It won't be as tight against sloppage slipping through as your design, but because it has much of what you designed it will make a big difference.

Thanks for not taking my criticisms of the sheet as insults.

Your sheet will save engines and it is the only thing out there.

Just don't expect the sheet to allow you to ride quarter mile wheelies or quarter mile accelerations up the world's steepest hills without damaging the engine.

The sheet will protect when the front wheel briefly rises and up most of San Francisco's hills.

My engine has survived many miles of hard use racing up hills, but not San Francisco's. If I had had a sloppage sheet I probably would have quadrupled the life of the main bearings.

It may be too late to save, but who knows, maybe the engine is now simply loosey goosey and the sheet will help keep it that way for the next 8 years :D

Thanks again!

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