Oil Temp reading

[Goo'Roo]

On my turbo Gsx1100F I have a sensor on the sump drain plug.
I have the feeling that the temperature read is to low.

 Driving hard on a mountain pass the temperature reached just 100° on a Motul 300V 10w40 but the engine sounds like it was really too hot, with increase of vibrations and gearbox issues. 

Where do you read the oil temp? I thought to add a second sensor to the engine head oil feed and change to some thicker race oil like a 10w60 (Motul has a 15w50 300v)
I defo need a second oil cooler to the head too.

[Gixer1460]

Depends on what you want to know from the temps? As now its oil temp going to bearings, if you want to know hot hot the engine in getting then the sensor needs to be in the cyl. head somewhere in the flow of oil to the drains or within the drains. Both will be different!

[Goo'Roo]

I need to understand why a so high quality oil feels out of specs..

[Gixer1460]

You say 'Mountain Pass' ? So one could assume a bit of altitude? lower air pressure, both give poorer cooling performance but also engine performance - usually messes with carbs the most! So it may not entirely be the oil's fault!

[Goo'Roo]

I'm not talking about performance. 

I have weird engine vibrations and the gearbox feels fragile when the oil reading is just 100°.

 

[Oilyspanner]

When engines get really hot they don't run well and cause vibration amongst other things. The 100 degree temp. in the sump is the coolest the oil gets from it's return from the cooler, it'll be a lot higher in the rest of the engine - use the 100 degrees sump temp as a marker to pull over and let the engine cool down from now on. If our engines had more electronics they'd retard the spark etc and if they had fans, they'd been on long before. 300V is lovely stuff, nothing wrong there. I had a big bore gsxr750wt back in '96, the tuners hadn't reconnected the fan lead, stuck in a queue going into Brands Hatch the thing began to run like shit, I pulled over, turned if off and found the loose connector - soon as the temperature came down, all was well - it felt and sounded pretty sick before I turned it off - could've blown the head gasket being a w/c.

Even pretty stock oilers can over heat in traffic during hot weather - tuned bikes are always prone to over-heating. The time to be worried is when the bike doesn't feel/run as normal once cooled down. You'll need to change the oil often if the engine frequently over-heats.

[Goo'Roo]

The bike is fine once cooled down. It runs pretty well until the oil is at 90/95° in the sump. After that it feels too hot.
I need a second oil cooler and and intercooler. 
And a thicker oil to cope.

Edited March 7, 2019 by Goo'Roo

[Gixer1460]

Thicker oils won't help with overheated oil......... control the temps with the right grade oil - winner winner chicken dinner!

[Goo'Roo]

18 hours ago, Gixer1460 said:

Thicker oils won't help with overheated oil......... control the temps with the right grade oil - winner winner chicken dinner!

I do not agree completely. Yes of course keeping temps down is crucial, but there are some race oils formulated to cope with very high temps that help not to destroy your engine in severe conditions that can happen.
Then fuel diluition with very rich afr is to be considered too with oil viscosity and capabilities.
With a 10W60 race oil I'm only worried by the first minutes of engine working, not during operating temperatures.
I live in Bologna, slow speed, mountain passes and very hot summer temps..

 

Edited March 8, 2019 by Goo'Roo

[Gixer1460]

2 hours ago, Goo'Roo said:

With a 10W60 race oil I'm only worried by the first minutes of engine working, not during operating temperatures.
I live in Bologna, slow speed, mountain passes and very hot summer temps..

In that case then a 10w60 will be no different to a 10w40! If it is start up viscosity then a 20w50 would be of benefit although this will generally hurt operation as engine not designed for it.

[Goo'Roo]

10w40 and 10w60 have totally different viscosity when cold, even if they show the same value, with the 60 much thicker. 

Just check some tech sheets on the Motul site for example.

 

 

[Goo'Roo]

Look at this official bike,  the main oil cooler is for the head and sacs system. Weren't there some oil pressure issues with a big cooler?

 

[dupersunc]

On 3/8/2019 at 12:29 PM, Goo'Roo said:

10w40 and 10w60 have totally different viscosity when cold, even if they show the same value, with the 60 much thicker. 

Just check some tech sheets on the Motul site for example.

 

 

They are both 10w viscosity when hot. 

Modern synthetic oils are fine to 130c. it does sound like you need more cooling as you say. Stock oil cooled motors struggle when ragged hard.

Fans do bugger all above 20mph. only useful in traffic jams.

[Goo'Roo]

First value is for the cold viscosity.

And if you compare tech sheets from a 10w40 and a 10w60 you'll see that cold viscosity changes also even if they share the same value.

Just go on Motul internet site

Edited March 10, 2019 by Goo'Roo

[Oilyspanner]

On race bikes they liked to cool the combustion for more consistent power, oilers used to lose a fair percentage of their early race power later in a race - the net average oil temperature will be the same which ever way round you put them though. On the big bore Yoshi racers they used 3 even 4 oil coolers, even had them burning methanol to keep the temps down !

My initial thought with that racer was - that engine sits high in the frame and look at that suspension linkage !

The first number in oil specs is the cold figure, diesels use 0W40 and 5w40 etc to ease cold running (thinner oil) and help mpg. I reckon your best bet is to run another cooler as has been said, your oil pump will be fine. As Dupersunc has said, a fan is only good at low speed to pass some air around when the temperature always creeps up.