Oil pressure switch/oil temp. sensor locations

[Ducatl]

My question is this... I'm swapping gauges and therefore ditching the dummy lights on the stock guages, does the oil pressure sensor switch located just above the oil fill cap serve any purpose other than to illuminate the oil light on the stock gauges? I think I've seen people running without them before...

Alternatively does anyone think oil temp. can be accurately picked up from either the pressure switch location or the oil fill plug location?  I know the Motodetail unit uses the fill plug and I haven't read of any complaints...

Before I measure myself...does anyone know the thread size/pitch of the oil fill and/or drain plug?

[Slide Panda]

The pressure switch is a single purpose item. It just lets you know if the pressure dips below the specified min (can't remember it off hand).

Until the immobilizer dashes came in, monsters did not have temp guages. Save for the addition of some computer gizmos the 2v engines have changed very little over the years... so you can probably do without - though someone like DucStew or SpeedDog might have more technical insights.

As far as position - the ideal place to take the temp would be to have the sensor immersed in the fluid you're trying to measure. But, having something on the case around the filler would probably work pretty well 9for an accurate notion of the temp) once the overall engine temp evened out.  Obviously the oil and the case are going to be about the same temp most of the time since they are constantly in contact.

No notion as to the pitch of those threads... sorry

[Speeddog]

The oil pressure switch is 'closed' until the pressure exceeds a certain value.
The last one I checked tripped at 6 psi.

The temp sensor location on the '02 and later ducs is really good, it's at the oil pickup screen, so it's always immersed in the oil that is being delivered to the motor.

[numbskull]

The temp sensor location on the '02 and later ducs is really good, it's at the oil pickup screen, so it's always immersed in the oil that is being delivered to the motor.

This is far more accurate than the Motodetail oil-fill plug/thermometer. I have one and the temperature is always several degrees cooler than the stock readout on the dash. Although, it does look cool and is sturdier than the stock plastic plug.

[Ducatl]

Good to know,

What I've learned so far...

The stock oil screen bolt on older at least pre '00(meaning '99 and down) 750 monsters is a single unit that appears to have some special machining on it and is without a threaded pickup pre-machined into it.  If you wanted to go this route you'd need to drill and tap the factory bolt.

The oil drain plug looks like it may work but I've yet to get it out and measure it, I'd rather not have the sensor under the bike and complicating the drain plug but it may be the most feasible option...I'll report back with bolt measurements.

The oil pressure switch theaded portion is actually rather tiny...but the sensor is only an m6x1.0, once I measure the switch I'll let you know what it turns out to be.

I don't think I'm gonna use the fill plug simply because it has that weird machining for the o-ring and I don't want to risk it leaking.

Anyways, More soon.

[Speeddog]

Oil pressure switch is an M10x1.0 thread.

Drainplug location would be a poor choice, as the drainplug has a magnet, which you need to assess the health of your motor at oil changes.

[Ducatl]

Yeah, I thought of the magnet issue as well.  The other problem is that the plug itself is physically huge.

So here's what I've come up with.

Like Speeddog mentioned the pressure switch is an m10x1.0

The fill and drain plugs both seem to be m22x1.5

I checked out my local spot for adapters and came up with nothing, I'm gonna check online suppliers as well but at this point I think the simplest and cleanest method may actually be drilling and tapping the screen bolt...

[Speeddog]

Which engine do you have?

[Ducatl]

it's a carbed 750 from '99.

I think I may have been looking at an odd bike but I'm guessing now that the temp sensor slides in from the m12x1.0 bolt spot that's right under the screen bolt?

either way...m12x1.0 is not gonna be easy to find

[Speeddog]

You have the 'old style' screen.

New style has a 'cover' which has the sensor screwed into it.
Screen is seperate, underneath the cover.

Don't mess with that other screw.

[Ducatl]

Right, that figures.

I originally thought the sensor was screwed into the cover/bolt itself.  Anyways, that rules out the other screw I suppose.

Back to where I started.

[Ducatl]

So, my options are now...

Buy an m10x1.0 bolt(not too hard to find) and try to drill and tap it for an m6x1.0 sensor

Try to drill and tap the older style screen bolt...is this even feasible? the bolt head and brass piece are somehow connected, anyone know how?

Locate a newer screen and hope it fits in the old space/they haven't changed the threading on the bolt/I can somehow mount the new sensor in the old location...seems unlikely

Off hand does anybody know the size/threading of the lines for the oil cooler? maybe I can find a little sensor adapter to mount inline with the cooler.

[Speeddog]

"Off hand does anybody know the size/threading of the lines for the oil cooler? maybe I can find a little sensor adapter to mount inline with the cooler."

That's your best bet.

New style screen and cover are not interchangeable with the old style.

You *may* be able to drill and tap the screen...

[ducpainter]

A '99 750 SS has a one piece screen with a tapped hole for the temp sensor.

[Speeddog]

A '99 750 SS has a one piece screen with a tapped hole for the temp sensor.

There you go, the ultimate solution!