Weegie

I think I've now about reached the end of this but wanted to post some more prelim data for now and some more test results tomorrow. Who'd have thought I could spin out a 4 page thread on a bloody spring. So here's what I've found as a rough guide regarding shimming the OEM valve with the Griso spring. Below are 2 results, the first colum is static test data. In other words putting the valve in an oil tester or pumping up the valve on oil, if you use air the results will be different, probably lower from what I saw. I gave up on using air as a medium the leakage was so bad I couldn't obtain repeatable results. The oil I was using was a 15-50 full synth room temp 18-20C, cold oil for both the static test and the crank test. When static testing the valve just starts to crack then around 5psi later is well off the seat so it's difficult to pin down an exact lift value, but easy to get a ballpark within 5psi for when the valve lifts All results psi, shim numbers in mm. On all of these there was no crush washer or shim on the spring retaining nut on the PRV top, some have these installed others not. IMHO they serve no purpose, however, if they are in place they will subtract from the shim value as the nut will not penetrate as deeply into the valve body and compress the spring Shim Static Oil Pressure None 80-85 68 1.5 105-110 82 3 125-130 95 I think the results were pretty well linear in behaviour, so as a "Rule of thumb" for every 1mm of shim compressing the spring you'll see 14psi increase in static lift pressure and approximately 9psi on the oil pressure. Can only base this on my own anectodal evidence, but knowing that no shim gave me 68 and 3mm shim gave me 95, a 27psi difference, 1mm equated to 9psi. 1.5mm should give me pressure in the bike of somewhere around 80-83psi. When I crank tested it was somewhere between 80-82psi. If you have a facilities to static test by all means do it, you may get different numbers to me, but be aware that the static lift values are higher than what you'll see inside the engine. The figures here are just what I saw and posted up as a rough guide and starter for anybody mad enough to try it

Thanks Tim Looking at some of the comparisons, I think the valve in the bike as of now isn't as good as when I conducted the first test. Whether this is because this valve isn't preloaded (allowing some, or more, float), because the PRV clearances aren't as good or something to do with the lower setpoint I don't know. Hopefully I shall find out when I change the oil and replace the current valve with the TLM valve and Griso spring (still awaiting the new spring to arrive) which I will preload to 2 or 3mm. The idea being to mess with the valve internals as little as possible Looking at the first test and the most recent comparitive results are below, obviously nothing is exact here so a little latitude in reading the results is required. The main points I'm interested in are the 80C readings at elevated RPM. The second test valve has a lower setpoint and given that is the case (around 66-68psi) the idle results are all pretty much in line and way more than required. However the results at 80C 3&4k rpm are pretty stark around a 15psi difference. From what I see pretty much after 2.5-3k rpm oil pressure is constant with revs Same oil and same cooler (a 13 row, but smaller area, Setrab, with -8 hose and full flow fittings) so the only variable is the PRV. Motul 300V 15/50, full synth lube. 20C/idle 80psi 68psi 40C/idle 70psi 66psi 60C/idle 60psi 62psi 80C/idle 38psi 40psi 80C/3k 75psi 60psi 80C/4k 75psi 62psi Even as is it stands though its a big improvement over say the 43psi reported on @Lucky Phil thread page 5 by @Kevin_T . If I could get that 13-15psi back I'll be a very happy bunny, but for now at least I can rev it a little without fear of damage

I hear you Phil on the fairing, problem is that the Belly Pan helps to provide rigidity to the fairing. Might be an idea though to run some comparison tests with and without to see if there is any difference

Apologies Phil It's running Motul 300V 15/50 full synth. All tests have been conducted on that oil, so differing results have nothing to do with changes to the lubricant. Yes at the moment it's running the 1100 Sport PRV no spacer, Griso spring. The 1100 sport valve is the same part as the OEM HiCam engine's valve, the only difference is the spring, which of course is changed out for the Griso. I have another valve from TLM and awaiting a Griso spring for it. When that arrives I plan to douse the valve in oil and change to the Griso spring adding a 3mm, or 3mm with a 1mm spacer on top (effectively giving a 2mm spacer) onto the spring to preload it. The idea being it ups the setpoint and the extra preload on the spring might help drive the piston in the valve shut at higher oil temps (lower viscosity), in my case that would be normal running temperature of 80C and above where I think the valve will be completely closed. I could be wrong but I believe these valves are quite sensitive and should be liberally oiled when tested. If not the piston faces could get scratched and results in the valve passing even more than it does when it's new. If none of that improves anything I can see a move to 60 grade oil in my stars. I think Paul Daytona and one or two others already run the 60 grade. Differences will probably be ngligable, but as my engine runs hot, I think it's a reasonable move, if I still want to increase the pressure a little. One thing at a time though and change out the valve first. At the moment though I'm pretty happy thanks to all the help I've upped the pressure at least 10psi and probably a good deal more. So thank you to everybody for the assistance and it's nice to see some light at the end of very long tunnel

So couple of data points first a long boring video showing the results. Pressure is still a little low but I wonder if the pressure at the gauge is the same as what's at the crank, possibly a little higher at the crank. As the 2 valves run at this sort of pressure too I suppose it's nothing too much to worry about. Certainly better than in the 40s which I reckon the OEM will give you. Oh that Staining/drips on the tiles is some small leaks where the cans mate to the pipes, and the drips are water. There was another small oil leak from a rocker I reckon now fixed I'm just adding all this stuff as data points for others to let people see what the results I'm getting. Tomorrow I'll try to post a comparison of the different tests just for some more info to tie it together a little more

Ok thanks Phil that's really what I thought. Cheap reg to run with it about £20-30, plan to use 2 tanks I think (the beer cans) with a line between them to hold level, so not too bad It was just a drip about every 30 seconds or so wouldn't have affected the running but made a mess inside the Oz fairing, after a while. Pretty sure it was that rocker gasket that was missing, nothing above it and there were tell tales drips on the rocket cap screws at the lowest point. Everything else was clean(ish). Had a spare so it's now on and ready to try again Nothing to worry about, Oh I'll add a video to the Gross Stupidity Thread later today as I got some video and data. Thanks for chiming in both you and docc's input appreciated

Yeah it's an idea I do have 2x5 litre empty (a long time ago) beer cans. I'd need to do a little math though on what the rate is, I'm assuming the return is more that the bike drinks by some way so if it's returning a lot, running time could be limited, I could connect the tanks together using a line to balance them I'm assuming that the tank regulator back pressures the system and reduce the flow. I don't have a curve for the Bosch OEM on the bike, but a replacment Pierburg (IF it's characteristics are similar) is flowing about 100-110 litres per hour at 3 bar. With no regulator it would be higher with just the system components and hoses offering resistance...................I think!!!! That's partly why I'm asking the question, it wouldn't allow you much running time even regulated if you only had 5 litres to play with and no return. Saying that a Chinese Bay of Fleas regulator is pretty cheap and would be fine for just a test rig to run

No not on the HiCam @docc that engine has an external fuel pump (located at the head of the frame) In tank pumps were later Oh may have found the leak anyway, a PO had installed 2/3rd of the left rocker cover gasket, he decided to save weight an leave 1/3rd out, that looked like where the leak was eminating from but not 100%, I'll only find out when I re-run it. I'd still like to have a method of using a temp tank, as it's a handy tool to have

I've got an oil leak on a HiCam but where I've got no clue The easiest way to find it (& It's a good idea anyway for temporary use when testing) is to make a temporary tank/vessel to use a temporay feed. Ths would allow me max access to the engine and possibly see where the leak might be However being an injected bike I'll need to have a line into the temp tank for the return line So could I just run the line on the return into the temporary tank or do I need to rig up some sort of regulator to back pressure the system? I'm thinking I'll probably need something and wondering what I could rig up. Is there such a thing as in-line regualtor, I'm guessing they as simple spring and diaphragm devices but don't know. John

I got a lot of stick on WildGoose for saying the Daytona front forks were nigh on useless. It was a shame and a huge mistake by Guzzi to intorduce a new frame design with crap forks. I'm sure a lot of people thought the frame was at fault. Of course in typical Guzzi fashion, the stable door was closed, they were replaced with WP units, long after the horse had bolted. Anyway, when the BEARS racing was happening the few brave enough to enter a Guzzi Daytona, usually changed to GSXR forks, it's a road that's been well travelled and repeated by many owners, I'm ASS-uming the Sporti wears the same or similar front end. Personally I never tried it, as at time I never had the cash

Well bet you were all thinking this was dead and gone. So after removing my OEM V/V with Griso spring to try to lower the presssure a little I then couldn't get the valve to seal well again. I purchased an HMB valve and tried that but although I did get static tests that looked great whenever I put it in the engine I just never got the pressure I was expecting. The only explanation I can think of for differences I experienced between static and engine testing, is that oil pressure in the bike is constantly fluctuating probably at quite a high frequency so the valve is constantly chattering and you can't replicate in a static test. Anyway I took the PRV out of the 1100 Sport which is identical apart from the spring and used it with the Griso spring in. Static tests with the 3mm spacer showed the valve lifting at 120psi, a tad too high for my liking so I removed the spacer and got the v/v lifitng at 85psi. Put that in the HiCam engine and did a crank run, 68psi.................Hmmm Today I ran the engine, cold oil idle was around 80 psi and when the oil got hot 60-80 C the valve seemed to be controlling at 68psi. Before I had 83psi setpoint and the valve controlled throughout the range, but I think because now with the lower setting of 68psi, what's happening is the valve lifts earlier and the system pressure vs the PRV lift pressure is a larger delta. So when the oil is cold the valve gets choked and system pressure rises above the valve setpoint. I'd ideally liked to have the lift pressure to be a bit higher but learning from my previous experience I'll leave it at 68psi and call it "job done" Even at this lower pressure setting it's night and day over the standard spring with its 55psi cold idle and lower operating pressure throughout the range. Finally it looks like I've arrived at, if not the ideal solution, pressures that seem reasonable. The next question is how will this affect cooling? I'm hoping the higher system pressure will lead to the engine possibly ruunning a bit cooler, but that's for the summer and a good run out.................and that's a bit away yet

Count me in!! Me..............all the gear and no idea. If I wasn't so dammed old and had other shit to do I'd be building a Guareschi as well and it still might happen. Of course throwing my aging corpse into the saddle might be another issue

Gotta be "Medic Andy" on WG surely

Thanks Phil Here was me labouring under the misapprehension that the temperature viscosity relationship was linear, which it clearly is not From that graph it appears that after 70C and certainly after 80, a temperature approaching normal running condition, that the viscosity changes are pretty much negligable Very interesting

I did mean to comment on this Phil, as I'm seriously considering both The Griso spring will help to hold the pressure as the bike comes up to temperature and eliminate some (but not all) leakage. However when the engine's hot, 80C+ oil temp the max I obtained at 4k RPM was 75psi. The relief is closed at running temperature and only oil weight will have any effect on pressure. 75psi is sufficient and I'd be more than happy enough with that (and continue to run my 15/50) IF the engine temperature stabilizes at 80C. A shakedown run will be the only way I can establish the true hot oil temperature and Winter is knocking at the door here. It appears that after around 3k the pressure maxes out and increasing revs to 4k did nothing to increase the pressure. I can't say for sure that it doesn't rise at revs above 4k but from the data I've gathered so far it certainly looks like it's peaked by 3k RPM. John

Hi @Twin AH I've got some pictures of the teardown and install of the Caruso gear and pump change. At some point I've been hoping to a do a "how to" if that's what you're referring to, but it hasn't happened yet. I don't know of a single document or place where all the mods are listed and it all depends on how far you want to go. I'm sure Lucky Phil will chime in and he's the real expert. As far as the Griso spring change out, I'm the only person to have done it as far as I'm aware and the bike hasn't even been out on a shakedown run, although the results are encouraging. The problem as far as I can see is the original spring is too soft and so starts to lift early. The Griso spring is much more positive helping the valve to seat and only lifting at it's setpoint. Once the engine is up to temp the valve will be shut (but probably still leak a little it's a rotten design), The OEM spring will probably still float and rob the engine of oil flow. I haven't done extensive testing with either but a few have reported that running oil pressure can be lower than I'd personally be comfortable with. Have you read through Lucky Phil's Hi Cam build? That's a great place to start. https://www.v11lemans.com/forums/index.php?/topic/20664-v11-daytona-project Part number for the Griso spring is 94321077 All I've really done of significance is the Caruso pump & gear mod, the Griso spring and installed a different oil cooler as I didn't like the OEM setup, due to the 4 banjo fittings which I reckon will introduce a signifcant pressure drop across the cooler. However with the exception of the Caruso gears and pump, I can't recommend them any of them yet as the bike hasn't been out on a proper run to asses them

Oh @Kevin_T to also answer your question on why Guzzi didn't do it from the get go. I can only surmise, but Guzzi were not in a good way during the 90s and could barely keep their head above water, the situation getting worse as the 90s went on and into the early turn of the century. I think they were desperate to get a new model out and increase sales. The HiCam engine was not a well developed product, it was a race bike engine to which the minimal of changes were made to make it just about suitable as a road machine. There are many flaws in the design which were probably only really seriously addressed when the MGS-01 was designed. It probably wasn't perfect either, I don't know enough about it. The MGS heads and oil flow to the heads are different in many aspects. Back to the HiCam, for goodness sake you need to remove the service shaft pulley to change the belts on the OEM design. You'll hear Chuck often comment that the only reason they assembled the Centauro was to make sure you got all the parts. The relief valve is probably only one of a long list of things that should have been sorted. They either found or thought that with the increase in oil flow required they'd just make the pump bigger, leading to the "grenade with the pin pulled" pump design and shim the exsiting spring in the relief valve to increase the pressure setpoint and that would be that. What I found when I swapped over the 1100's relief valve which is set 10-14 psi lower, there was no change still the 50psi cold oil idle. That leads me to think the spring in that valve although working well with the 2v/v engines is unsuitable for the HiCams. At 50psi the pressure is below both the 2v/v and of course 4v/v setpoint. I suspect (but don't know) that the spring is too soft and the valve is partially lifting. That's been proved through Phil's rather over enthusiatic spring holding the valve shut and seeing system pressure build to way in exceess of that required on cold oil. It can also be seen on my engine run test with the Griso spring earlier in the thread as well, where the pressure holds 82 on the relief valve setpoint. The Griso spring though shorter is stronger and heavier, holding the valve shut, the valve still passes but not nearly as badly as with the OEM spring. From my rather limited engine run you can see how much more positive the relief valve action is. Rather than the valve floating slowly open on the OEM spring, the pressure rises until 82psi (that I had as an aribitary setpoint) then "Boom" the valve opens and you can see the gauge fluctuating in response to the valve chattering, constantly opening and closing at its designated setpoint.

Hi Kevin We did chat briefly on PM if remember correctly. It all seems so bloody obvious doesn't it when it's laid out and if I had listened to @Chuck I could have saved myself 2 years (or more) worth of fruitless grief & pain. He initially pointed me on the right road on WG a long time back. Like you I thought the problem was pump or leak releated. I started down this road for the reasons Phil pointed out on the post above yours, convinced the temp and pressure problems were related (the jury is still out on that). As far as low pressure it just didn't click that the relief was the culprit, due in part to my experience with the 2v/v engines (Big Mistake!!). It all really started to make sense when @Lucky Phil started to intervene and the majority of findings were down to his engineering ability. Starting with his engine build thread, then his experiment with the over enthusiastic relief spring and then another buddy with a HiCam installing a pressure gauge. The results obtained all pointed to 50psi being a standard cold oil pressure. Following conversations on PM with Phil he patiently pointed out what was happening one step at a time. I'm really grateful to him and so should anybody else with a HiCam who wants to sort it. Joe Caruso also provided me with some eye opening data on the pumps and a lot of assitance (you'll not meet a nicer guy than Joe) So to get to your questions, so far I'm testing on a 15W 50 full synth, Motul 300V. There isn't so much changing in the systems as far as I'm aware. The bike has the Caruso pump and gears, but has had these since the problem started. The only other change is I've taken off the OEM cooler and installed a Setrab 13 row, it's actually smaller than the original but has full flow fittings and Dash 8 hose to and from the tapping points on the broad sump. Tests there showed the same cold oil pressure before and after install. I'll need to get the bike out on a shakedown run to tell if the cooler has made any difference. From looking at the OEM install though I "think" these banjo fittings must be introducing significant pressure losses across the cooler, which won't help the amount of oil going through it. The rest of the system is fixed pressure drops being controlled by the available areas and pathways the oil has to traverse. Once the relief is removed and tested it's obvious where the problem is, testing it on air (or preferably oil) will highllight it. The Griso spring was Phil's suggestion, all I've really did is to provide a test bed and do some donkey work. Which was Ok as the bike was partially disasembled anyway. I'm at a bit of a loss on your suggestion to run a lighter weight oil, so forgive my ignorance. Generally these engines run on the hot side and even at 80C on a 50 weight at 4k RPM the pressure with the relief closed is 72-74 psi. I expect that during normal running the actual oil temperature would be 80 at best and perhaps 90 or in excess of 100. I'm in agreement with Phil that if I change oil grade it would be better to move to a higher weight to maintain viscosity at the higher temperatures. John

Phil is the rating not 4 bar? The actual pressures I converted from the manual which aren't measured in bars but kg/cm^2 for the 2 valve sporti was 3.8-4.2 (56-60psi) and 5kg/cm^2 for the HiCam (70psi) I'm guessing here but I'd have tought that the V11 would be the same are the Sporti 56-60psi The problem is only related to the HiCam, with the valve set for 56-60psi the valve will choke cold oil idle and typically a 2 v/v engine will idle somewhere between 60 and 65psi The HiCam has a large oil flow to the heads so the valve has to lift less to drop the oil pressure more, so despite the higher setpoint (which I'm unsure was ever set at the factory) the HiCam at cold idle will register 50psi. The 2 v/v engines are much more tolerant to relief valve leakage and these valves seem to work just fine. I don't know the effects of upping the pressure on a 2 v/v engine would be, but I don't think there would be any benefit. Given they run just peachy on the 60psi setpoint, it would seem a bit crazy to start messing with them

Yeah I did say something about that in the photograph notes Phil but probably not clearly enough, so thanks for pointing it out again to ensure anybody looking at this doesn't get confused. John

Not a problem Pete at the moment I've got the small Setrab on it with Dash 8 lines and full flow fittings. On the video you can here me say I got a leak, need to run it again to see if I've managed to sort it. With the larger diameter lines and full flow fittings, the lines immediately started to warm up, something that isn't nearly as noticable with the standard set up. I think that could be due to the OEM banjo fittings introducing pressure losses and restricitng flow to the OEM cooler Let me know postage costs wouldn't want you out of pocket There was also a leak coming from somewhere on the engine but I'd be dammed if I could find it. It was getting onto the spine frame and running down it then dripping at the Gbx end cover. I think it was coming from the dizzie blanking plate which on the HiCam carries the two head return lines to the crankcase (or are they breathers?). When I took the airbox off to look, I was expecting oil everywhere but virtually nothing..................go figure Going to remove the airbox and run it again to see if I can pinpoint it. I'm as bad I need to contact my painter about these Magni decals, I've not heard a thing from him.

One more thing I put rather clumsily was in the tale of the 28psi idle pressure and the statement "50psi and even that's is really too low" when referring to cold idle presssure. 10psi at idle is more than enough, what I was trying to get across was on cold oil idle the relief valve is partially lifting/leaking and the setpoint that should be on the valve is 70psi, however they all lift early and idle at 50psi. Revving the engine will raise the pressure, choking the valve. I reckon It rises to a bit over 60psi at 3k rpm but I don't know if the pressure rises any higher than that. From what I've seen from the short Griso spring test I suspect not. As I also have a Sporti I swapped the internals of the sport pipework into the HiCam to test, when I could not understand why I was getting low pressure at idle. The results I saw when cranking were identical, I actually started to question my sanity and repeated the whole thing twice as I could not believe the results were identical. Both valves showed the same system pressure of 50psi. The Sport engine's relief valve pressure is around 1 bar lower, Guzzi quote 56-60psi for the 2 valve engines and 70psi (no tolerance) for the 4 valve. Then I checked the parts book, well, well, well identical components including the spring in both valves....................Go figure. I believe the intention was to shim the spring to obtain a higher relief pressure for the HiCams. They either weren't shimmed in the factory or the spring rate so soft as to make no difference to the observed oil pressure. The lower pressure seen when the valve lifts on the HiCam is due to the large oil flow to the heads, dropping the pressure dramatically. When that same relief valve is used in the 2 V/V bike it will idle circa 65psi cold oil. I can only surmise that due to the rushed design and pressure (bad pun) to get a bike out the door with more horses, very little thought went into the design which, as a result meant the system just didn't work the way Guzzi envisaged.

Damm I meant to say on the video if anybody is contemplating this as a mod, what I didn't realize at the time was that there was 3 mm spacer jammed into the top of the valve as a shim. Like the dope I am I completely missed it and only found out about it later when messing with the valve again So the valve had the 1mm crush washer installed on the outside at the top of the valve which reduces the spring tension and a 3mm shim on the inside of the top bolt which increases the spring tension. If installing without the crush washer (which IMHO isn't necessary) I'd start with a 2mm washer/spacer. As Phil pointed out, and I found out, the only sure fire way to reliably determine the lift pressure is to use an oil tester. I've been using air and found that the valve lifted approximately 10psi earlier than when actually tested on the cranking/running engine. Picture of the valve to make things a little clearer

Perhaps you're correct Phil, it's a personal thing and specific to these engines. It's a backup to the rather unreliable pressure switch, known to fail. I rarely monitor the gauge on a ride, its just something I glance at from time to time, or if something else occurs (like the pressure light illuminating) to provide me with a little more information. Maybe my poor tech skills, but over the years I've found the gauge useful from time to time. A compromise would be to install a temporary hook up to monitor pressure for the shakedown runs and then remove it. Vive La Difference John

That was probably me Kremmen, I've got a HiCam engine that was/is overheating. Anyway I posted about the travails on this thread https://www.v11lemans.com/forums/index.php?/topic/21884-hicam-oil-pressure-gross-stupidity-and-why-you-should-always-listen-to-chuck/ It may have been there as I made that statement on that thread Due to all the research I did, while basically going down the wrong road, I was frequently in correspondence with Joe Caruso and that was where the information came from If the gear pump output is linear with RPM and gear rotor length similarily linear to pump output, then the lower flowrate is significant, although I've never heard of anybody who did this mod report problems...............however very few owners install pressure gauges and I have no idea what sort of mileage or how many of these mods have been completed. The V11/MGS conversion will have the oil pump running close to 10% slower and the V11 pump rotor length is almost 25% less than the OEM Daytona/Centauro parts. Apart from the Caruso gear and pump mod My advice is install an oil pressure gauge (and some method monitoring oil temp doesn't hurt either). Make sure that the pressure relief valve is opening at the correct pressure (they nearly all don't) and that its sealing when shut. As far as lubrication these engines need a stupid amount of oil to the heads and the 2 big weak points are the oil pump and the relief valve. On the relief valve and low pressure a friend is putting a HiCam back into service and I urged him to put a gauge on. What he found was the relief leaking badly and his pressure (cold oil) was 28psi idle normally they will show 50psi and even that's is reallly too low. With no gauge he'd have probably have been out running around thinking all was great as the warning light wouldn't trigger (although it may have once the engine was up to temp). I do wonder how long though the engine would have lasted like that and the amount it could have potentially cost him. Yet I still get owners telling me that a gauge is waste of time and doesn't tell you s**t.........................each to their own I suppose