dlaing

I read the word proportional to indicate infinite values, constantly variable, no just the 2 values that you measured. Given your measurements I think they were incorrect when they said, "The regulator varies the fuel pressure proportional to the vacuum applied" Sorry again, for not reading your reply to Ryland.

Even at a mile high?

http://www.v11lemans.com/forums/index.php?showtopic=5395

Thanks! Your evidence is fine. I completely believe you. Sorry, I don't like reading red text. Too many horror films??? Ryland, will you please fix the FAQ, already?

I am not accepting the following as gospel, but it does support our earlier assumption: "The fuel arrives at the regulator under high pressure (>3 bar), and unused fuel returns to the fuel tank from the regulator, thus forming a continuous flow of fuel around the system. The pressure regulator sits at the end of the fuel rail, and guarantee's that the pressure in the fuel rail is constant. The regulator varies the fuel pressure proportional to the vacuum applied to the vacuum pipe feed pipe on top of the regulator. When the throttle is depressed, and the vacuum in the inlet manifold reduces, the fuel pressure regulator increases the fuel pressure, to cope with the extra demand from the injectors." http://www.zetecinside.com/xr2/injection.htm Looks pretty similar to our FPR

We are thankful for the data you offered. I poke holes in the testing when it is questionable. I have not tried to poke holes in anything that you showed test results for. I have simply said that "I am not sure I believe you" in what you did not show test results for!!!! And even then, based on no test results and just your word that I am not sure I believe, I suggest Ryland change the FAQ that says "This port allows the regulator to vary its output pressure with the intake manifold vacuum when connected to the throttle body intake manifold ports. At wide open throttle, when intake manifold pressure is nearly atmospheric, it has no appreciable effect. At part throttle, it lowers fuel pressure to lean the mixture." How is that accepting assumptions as gospel?!?! I am leaning more towards your assumptions, than the previous assumptions, but you think because I don't buy them lock stock barrel, I am accepting the other assumptions as gospel????? You have shown no EVIDENCE! If your testing showed more than simply, "I'm guessing the spring is overcome at about 10"Hg." or that you simply applied 15"Hg of vaccum and read the gas meters, then I would not question that vacuum/atmosphere side of the regulator acts as a cut off switch at a specific vacuum rather than a progressive modifier to the fuel pressure regulation. If you find it unreasonable for me to question that in the face of NO evidence, than tough. If you had said that you applied vacuum progressively, or in stages of 5"Hg, until you saw the switching point then I would believe you. Or maybe specs from the regulator's maker??? Ratchet's testing showed nothing happens, and I poked holes in it, and thankfully your evidence showed his testing as essentially useless and possibly misleading. And not one Mea Culpa from ol' hatchet. And both Ratchet and Raz suggested that Load won't effect fuel demands at a given fuel cell and I did my best to poke holes in that.

Is that guy licking his own foot?

Here is picture of Antonio giving his Austonio Powers, "am I sexy?" pose.

I was not sure what the correct level is. I thought I set mine to about 100 or 110mm,based on the generic R&T fork manuals, but I finally found the Guzzi manual's recommendation for the Ohlins, 105mm from the top. I better check mine... Thanks, that is good to know that double lipped are better.

DUDE! come back down to earth AN ORDER OF MAGNITUDE!!!!!!!!!! An order of magnitude would usually imply ten times better. Well, you got me beat Nurse Ratchet. My Ohlins are only about twice as good as my undersprung Marzocchis. Anyone want to trade my Ohlins for a pair of 1.1 forks? Ratchet has me convinced that I wasted on my $2000 and could have gotten five times better performance than the Ohlins from a pair of $100 springs.

Filled very carefully to what level? I keep mine over 100mm from the top. You could be right about not riding regularly. I am blessed with weather that does not force much down time. But I often fail to find time to ride. So there have been a few three week periods where the bike just sat.

I'd agree that each map cell can accurately ENOUGH determine the proper pulse width to match the ESTIMATED air mass, but it is only ESTIMATED and it will vary with load. How much it varies I don't know. All I know is that if are going down hill and you whack the throttle to 100.00% and if you are going up hill and whack the throttle to 100.00% you will get an instantaneously different demand for timing and fuel mixture despite the fact that you are at the same map cell. Before the engine position sensor can determine that the RPMs have changed, the piston on the power stroke is facing more resistance going up hill than down. What happens on the next couple of engine rotations, I am not sure exactly. The ECU receives a different time measurement between engine rotations depending on load, but at the first and second engine rotation after the throttle is opened,the RPMs have not changed enough to change the map cell position significantly. Maybe we can add a sensor to the polymer cush drive to measure load? As more rotations pass I would guess that the map gets closer to sending the ideal signal for the ideal pulse rate, but the load always creates a different demand for ideal pulse width. I suspect it is better to tune for the high load than the low load. Maybe someone else can explain better or show me where I am wrong...

What would my beliefs have to do with your qualifications? Until you present proof, I can't be sure you are correct. There have been countless pages of posts on this forum making the assumption that there is a relationship between vacuum and fuel pressure, and you are the first to assert otherwise. FWIW I believe you enough to recommend a change to Ryland's FAQ http://www.v11lemans.com/forums/index.php?...view=getnewpost that says "This port allows the regulator to vary its output pressure with the intake manifold vacuum when connected to the throttle body intake manifold ports. At wide open throttle, when intake manifold pressure is nearly atmospheric, it has no appreciable effect. At part throttle, it lowers fuel pressure to lean the mixture." But I would still like to see proof. I guess you ain't a "question authority" type of guy...

TPS setting. If at 500-550mV at idle consider it not the problem for now, but it may need adjustment in any case. Like Quazi-Moto said, check the balance. Check fuel lines for pinched hose. Also, a wire could have fallen off one of the sensors. Or an ignition wire could be loose.

16K miles on Ohlins and loving it. No blown seals. Smoother ride. Better control. More stable. Imagine how good they'll be if I ever put the proper fork springs in!!! I have to wonder if those blowing seals are setting their fluid level to high???? IMHO the air spring is to assist the metal spring, not replace it.

Think what happens to the temperature reading through the brass housing when you drive through heavy rain at high speeds. Not that I would tape my fins as I am not sure it is wise to let the sensor get that hot.

Thanks. Redundancy helps. I am not sure I believe you, but I'll take your word for it until I see further evidence. For now since the fuel pressure doesn't need it as a reference, I think I'll cap off the vent since it is useless and the ozone exposure is slowly eating at the diaphragm.

I am using little plastic (nylon?) inline screw valves. I had bought a crappy set of vacuum dial gauges from "Cycle Gear" I could never get the gauges to stay in synch with themselves despite the umpteen calibrations. But the gauge kit came with screw valves, which worked great at damping the pulses, once I bought the Twin Max. Something like this could probably do the trick but the short quarter turn is not ideal. A thumbscrew valve is more precise. http://item.express.ebay.com/Home-Garden_O...cmdZExpressItem EDIT, Never mind that valve, this might do the trick http://item.express.ebay.com/PART-IN-LINE-...cmdZExpressItem Assuming 1/4" is right size Maybe a carburetor jet with a small orifice would nicely dampen the pulses????

No, it does not make sense. First you say there is no relationship between vacuum and fuel pressure and then you show that there is a relationship. But your explanation of the relationship is a good explanation of why vacuum is a handy means of changing the fuel pressure. You said the it regulates at two pressures. That makes sense, since otherwise the regulator would go crazy, constantly opening and shutting, trying to keep it at 3.0 bar. For sake of argument lets say that the regulator closes going from high pressure to 2.9 bar and opens going from low pressure to 3.0 bar. If we apply 0.0 bar vacuum we will get between 2.9 and 3.0 bar fuel pressure relative to atmosphere. If we apply 0.5 bar vacuum we will get between 2.4 and 2.5 bar fuel pressure relative to atmosphere. If we apply 1.0 bar vacuum we will get between 1.9 and 2.0 bar fuel pressure relative to atmosphere. Right? or am I missing something.

Interesting! I did not notice that it might slide there, only that it was locked in at the ball joint. But that offset does not look healthy to by two valve traditionalist bias swayed eyes.

I wrote To which Ratchet replied, Lu-Lu only if you don't try to use your noggin. But no doubt I was wrong and the formula is more simple, as Troy will later describe the math that Ryland used. Ryland laid down some numbers without showing the math... Since 2.5bar is about 83% of 3 bar, we have a reduction of about 17% in pressure, which I presume Ryland did further math to arive at a reduction in flow of 8.7%, but then Ratchet did not see the invisible math, so he said, And then Troy nailed it down. 41% of 17% is about 7% doing my sloppy math, which is not far from Ryland's probably more accurate 8.7% I think if someone wanted to give this a try they should consider no canisters and they should select a smaller orifice at the T to reduce pulsing just to the point where no visible pulsing occurs with a vacuum meter. I have dial cutoffs that I added to my Twin Max and they work great. If I dial them too loose, I get too much pulsing, but if I dial them too tight, I get a lack of instantaneous response. Luckily it is easy to find the happy medium right at the point where pulsing disappears. I think it would be trivial to find remedy to this through proper orifice selection Of course the other points do seem to indicate that it may not be a good idea to loop the FPR with the intake manifolds.

Thanks! One of these days I will read everything the man babbles on about, or maybe not. I disagree. What you say would only be true in a theoretical static condition where RPM did not begin to change. With less load the RPM will change faster. If the engine has a high load it will effect the manifold pressure. A higher load facing the same Throttle position and RPM will be more likely to ping. I can only conclude that if it is more likely to ping, then something different is happening to the flow and manifold pressures. Is that difference significant? Is more load going to result in more vacuum, or less vacuum? I don't know, but I know it will be different.

Oxymoron?

I am having trouble picturing what is happening in the manifold, but in the engine the 5th gear, 3000rpm, 75% will be more likely to ping. I think this will somehow effect what is happening in the manifold, but yah, I too doubt it would be significant, and closing off the pressure regulator's line to atomosphere probably won't make a significant difference. Likewise under any scenario of 75% throttle, I doubt there would be a significant difference. The significant differences would be at the throttle rpm situations listed with the greatest vaccuum being at about redline with throttle closed. Thanks Dan for the numbers and analysis. I am sure the numbers will vary, mostly depending on what you have the idle set too.

Maybe we need a poll to determine how many people still have the canister(s). I kind of assumed most people considering the mod had no canister(s). The diagram shows no canisters. Was your test done with or without canisters? If you have canisters, that would certainly explain why you noticed no difference!!!