Bonneville America Forums Forums Technical Forums General Tech low oil pressure

OK so at idle, my bike was barely pushing 12 PSI @ 200 degF. Sounds a little low compared to other guys. Also, my bike has always run a little hotter than others, so I wonder if it is either related, or just another one of those quirky things about my bike. Thinking of putting the other gauge back on to see if it is higher. By the way, when I twist the throttle, pressure goes right up over 60. Thoughts?

its gonna blow up

Frank

With those new coiles, it's runnin like a scalded ape too. Hard to believe anything is wrong with it, ya know?

Thats awfully low. Wendys and mine both are around 40 PSI give or take at idle when warm also rarely hit 200 deg. except in heavy traffic on a hot day. Is your bike idling low maybe? As soon as I hit the throttle on either of our bikes it jumps right up to 80 PSI. Is there a kink or restriction in the line to the gauge maybe?

Benny,
What was the ambient temp. when you noticed this?

Interesting Benny. I have the BP gauge and I'm about 18-20 on idle and 45-50 running hard. I've yet to see it at full tilt, might be because I'm kinda looking at where I am going!

I have the temp gauge too and I believe it's giving more the case temp than the oil. Still like it better than the stock filler cap. Here in South Florida, I run 200-240 regularly. Last year in NC, I never topped 180.

Right about 70 today.

Phil, I may put the BP one on just to compare. I had spilled a little oil during my oil change, so I thought maybe I was just low on oil, so after it cooled down I stood it up and it covered the sight glass...

Even 20 seems low to me. But you may be idling slower thus the decrease. Both our bikes idle at 40 PSI sometimes drops to 35 PSI at about 1,000 RPM (if you can trust the stock tach) And hit 80 PSI as soon as the throttle is twisted. Maybe you guys have more miles and the pump is a little more worn than ours too.

Actually 40 seems awfully high to me for an idle pressure. Not got the gauge on the bike but thinking about all the cars I've had they typically idled between 10-20psi when warm. I had one that'd idle at 8psi when warm and asked the mechanic I was working for about it - his response: "As long as you're getting SOME pressure at idle it doesn't matter. Start worrying if it doesn't go up when the motor's working hard."

As for the temperature I was worried about those gauges for that exact reason - they're showing case temp not oil temp and that's too subject to variation. What we really need's an electronic oil temp gauge whose sensor replaces the sump plug, but that's just begging to have the wire ripped off by the first thing you ride over.

Yeah my truck idles about 15 - 20 PSI and about 40 PSI at speed.As I have said before I am a mechanic by trade and thats normal for a car/truck in most cases.
I think the oil temp gauge gives a fairly close idea of oil temp. It is right above a gear that slings the oil right onto the sensor and the sensor is not touching the housing where it screws in. It may get some of the case temp but I think it's a good indication. It also gives you an idea of normal operateing temp and if that goes up , even if it is case temp you should be concerned.

I agree 40 seems hi. Could just be the different gauge... Most guys I have talked to run around 18. As for the temp gauge, I don't think of it as absolute temp, but relative. I know what it SAYS I run normally, so I know when I'm running way hot.

Quote:

---

Start worrying if it doesn't go up when the motor's working hard."

---

That's kinda what I was thinking too. I'd have to ride it a while longer to see where it finally settles, as my ride was only about a half hour-45 min.

The pressure is my mistake. I watched it at idle today and what I thought was 40 was actually 25 to 30 (fluxuates a little but anything above 3,000 RPM was definately 80 PSI. I never really looked that close at the gauge at idle once warm. I mostly watch it when riding or when I start the bike.

Take a quick look next time you are out for about an hour. See what it is. When mine is warmed up but not REALLY warm, it shows those pressures.

I watched it all day today I had 20 PSI once when the idle dropped. I was watching close so I was able to give you a good answer. I rode about 300 miles the ambient temp was in the low 80s at it's warmest my bike was about 180 degrees at it's hottest. But I regularly had about 30 PSI at idle at 1,000 RMP maybe a tad over I don't trust that tach 100%. Anything else I can tell you I'll be glad to answer or try short of hurting my scoot.I'll be out all day again Monday.

Oh ok, I thought you meant you just went out for a bit, I gocha now. by the way My idle is just over 1000 rpm according to Mr D Specialties, forgot to answer that a ways back. I must say I am comforted that the pressure is high when I first start up, and does imediately climb when I twist the throttle. I'm also wondering if I just need some thicker oil. Maybe some grade A amber maple

Thats possible and also like you said maybe switch gauges again to make sure you are reading right. I am fairly sure mine is correct or very close since Wendy and I read the same pressure. We have Triumph oil in at the moment too , if you have something thinner in that could be the difference too. As you say I would be much more concerned if the pressure didn't jump up right away when you twist the throttle.

Benny you gotta stop running salad oil in your bike, dude!

What if I stop at a farm stand tho?

I run 80 regularly and when cold it's over that. I know it kicks open somewhere above 80 I have seen it on the gauge but I forget what the highest pressure I have seen was.I am absolutely sure it was quite a bit over 80 though and the 80 PSI is an sbsolute certainty when out riding.

In dealing with oil pressure, I now have the guage but now need the hose fitting etc. But better yet, where to hook it all up. Also, has anyone thought about putting one of those little fans behind the oil cooler to be turned on when sitting at stop lights? Just a thought.

Crusty, send me a PM, I may be able to hook you up with a banjo bolt at least.,..

the line comming out of the engine case in the middle behine the jugs is where to hook up the gauge. I build my own gaige I'll be glad to help with what ever you need too.