Oil pressure dropping

[midmoraider]

Hey all, I put on one of the COO pressure gauges earlier this year. The bike was running between 8-9 psi per 1000 rpm. Today, went for a ride and noticed was only getting between 6-7 per 1000. Is this something to worry about? It was hot as hell here today, above 100, and I was riding around in town. Temp gauge was above the halfway point most of the ride. Didn't know if temps really affect the pressure once the bike has warmed up. Haven't noticed any performance or sound differences. I do have a valve cover gasket that has been leaking all summer. Not enough to even drip on anything, just seeps out a little. Would this cause a slight drop in the pressure? Sorry for the long winded post, but I'd rather be safe than sorry.

I also put on a new license plate bracket that I got from Custom Dynamics. It has an led brakelight built in and really goes well with Cop Runner's brake light mod that I did. Will get some pics posted later.

 

[SpecOps13]

The hotter the oil gets, the lower the pressure will indicate. You should be fine if you haven't gone too many miles on the oil you have in...

Cool Mods you did too......

 

[midmoraider]

I only have a couple thousand miles on the oil in it. What difference would that make in regards to the pressure?

Here are some pics of the newest add on. Since I had lowered the bike 2", I was worried about larger vehicles being able to see me stopping. The license plate housing is angled pretty good, so that trucks and whatnot should be able to see me better.

 

[tfisher65]

Oil viscosity breaks down as the miles and heat accumulate. The pressures you mentioned are nothing to worry about.

 

[midmoraider]

Great, thanks.

 

[RaWarrior]

I wouldn't worry about it, especially if it was extra hot that day. Lower viscosity results in lower pressures, so as the oil gets older, or it's temperature rises, indicated pressure will fall. Why you have 60psi all the time when you first start it and it drops off to the 7-8psi per 1000 once it's warm.

At 5000rpm, hot engine, I get around 30psi at a fast highway cruise. Hot idle I have 4-5psi. I have RotellaT 15-40 conventional, with probably about 3k miles on it now.

 

[gamorg02]

sustained highway runs make mine run similar to ryan. altho its never that low. 5krpms would be about 37-42 PSI.

if you can see it get to the bypass when hot i'd say you're in good shape (sean recommend this a while back).

 

[midmoraider]

Don't know what "seeing it get to the bypass" means. How do I do that?

 

[SpecOps13]

Thanx for all the back up guys, I'm a little late getting back with answers... Once the bike is warm and you romp it enough to get the revs up pretty good, you should see the oil pressure peak and quit rising at 62-67 PSI. That's where it bypasses to avoid developing too much oil pressure... That could blow the filter right off the engine if the pressure were allowed to go on up uncontrolled..

 

[midmoraider]

Gotcha. What sucks is I have a water pump mounted gauge, so looking down at it while really getting on it is somewhat tricky. If my o ring has started to pop out, would this cause the pressures to suddenly be lower than before? Sorry, don't have any experience with this.

 

[gamorg02]

Gotcha. What sucks is I have a water pump mounted gauge, so looking down at it while really getting on it is somewhat tricky. If my o ring has started to pop out, would this cause the pressures to suddenly be lower than before? Sorry, don't have any experience with this.

It might, but if you have the 60 psi at 6 or 7k rpms ( or even 8) I wouldn't worry about it. It be more worried at like 5 or 6 k rpms if you were in the 20s or low 30s even

 

[RaWarrior]

It might, but the "o-ring" is a problem that plagues probably 99% of Vmaxes, and people have gone well over 100k miles without issues, more than likely with a popped ring. The Vmax has a pretty high volume pump so even if a bit of oil is leaking from the elbow back into the pan, it isn't enough to cause a major pressure loss. Otherwise vmaxes would be locking up left and right a long time ago from loss of pressure.

The bypass valve pops open on mine around 60psi. Too much pressure would put strain on the pump, seals, and as mentioned if the bypass was disabled the oil filter would probably blow off the front of the motor if you revved it cold.

To get to the bypass hot, I need to be up north of 8000rpm. Could my o-ring be popped out? Quite possibly. Is it a problem? Not as long as there's oil pressure in the motor. 75mph cruising has me at around 4400rpm and around 25psi. Honestly I've never noticed how fast it has to rev to get to the bypass when hot, since if I'm getting on it that much I'm not paying attention to the gauge.

 

[Fire-medic]

I only have a couple thousand miles on the oil in it. What difference would that make in regards to the pressure?

Here are some pics of the newest add on. Since I had lowered the bike 2", I was worried about larger vehicles being able to see me stopping. The license plate housing is angled pretty good, so that trucks and whatnot should be able to see me better.

I like the Custom Dynamics light, as well as "copRunner's" light mod. I have a Signal Dynamics #02030 license plate light frame w/red LED's top & bottom & amber LED's on ea. side waiting to go on. Your visibility is greatly enhanced w/those two lights you installed! I recall riding w/my friend when his Sportster was new, 1st year of the 1000cc motor, & @ night I thought that little stock fender taillight was not adequately announcing his visibility to the rear. I had an H1 Kawi at the time and I had to watch for vibration-related bulb breakage of the filament.

On my FZR1K I added a Signal Dynamics license plate light w/o the amber sides, so top & bottom LED's, & it is a big difference in visibility!

 

[SpecOps13]

2004 had the oil pipe upgrade done, so the O-Ring's not likely to be popping out...

 

[COP RUNNER]

i I DID THE "O" RING FIX , I HAVE A "COO" GAUGE , IF I'M STUCK IN HEAVY TRAFFIC AND MY COOLING FAN IS SCREAMING , MY GAUGE READS " 0 " , BUT ITS A VOLUME PUMP !

 

[midmoraider]

Thanks everyone for the input. I am going to change the exhaust this off season, so I'll go ahead and drop the pan to look at the o ring then.

 

[COP RUNNER]

Thanks everyone for the input. I am going to change the exhaust this off season, so I'll go ahead and drop the pan to look at the o ring then.

i READ THIS THREAD WHEN YOU GET A CHANCE ! .. http://www.vmaxforum.net/showthread.php?p=76516#post76516

 

[Rusty McNeil]

Mine has/had 40,000+ on it and was making about 35 psi at 5-6K rpm. Would still get to the bypass at 60 psi. After installing a guage right after buying the bike I did notice that it takes a good half hour ride before it would drop to 0 indicated at idle as it always has.

I thought I was low at 35 compared to the 40-45 I use to get, but ran a lot of miles that way with no issues.

It's just me but 25 psi would kinda bother me a little, I would check the accuracy of your guage before making any decison tho......checking the o-ring and doing the o-ring fix, or doing Morley's HD oiler is about all you can do for this I think....But apparently like someone else said it's all about volume on these bikes not pressure, at least that's what everyone says.......

 

[Thevmaxrider]

Mine usually runs at low-mid 30's at 5k rpm and I am not too worried. Have an aftermarket oiling system from PCW installed which has the relief valve set at 80psi, which when cold is easily attainable, and know that the lower pressure number is just that a number. I noted a drop in my system pressure when I installed my PC Racing oil filter as well. A quick check with the manufacturer and they stated that their filter has a much larger surface area than a paper filter which allows for ~7x the flow rate hence the lower system pressure. Piece of mind is priceless:biglaugh: Also remember that as the oil goes through more and more heat cycles the polymers break down causing viscosity to drop which will lower your pressure as well. This also happens at an accelerated rate when the ambient temperature outside is hotter causing the bike to run hotter as well. Not sure where RaWarrior came up with a figure of 99%, but the o-ring issue is another consideration. Late models had some upgrades done to alleviate the problem. The primary cause of the o-ring popping is folks not properly warming up their bike and whacking it wide open throttle with cold oil.

 

[gamorg02]

i'd be concerned at 25 psi around 5 or 6 k as well rusty.