CLUTCH AND GEARBOX GREATLY IMPROVED (GS1200 LC 2013)

[TheBear]

AlanD the chart you have posted is that for air or watercooled bikes?

Hi Chris, that was just an example of how temperature effects oil viscosity's. The point I was making is that it is so hot here in SA so it makes sense to use a slightly thicker oil here. These specs on these german bikes are for European countries, much colder than SA.

Alan, it has been mentioned a few times and yet it comes up again.  Please help me understand.  An engine (any engine for the sake of the example) runs at 85 degrees C.  It will run at that due to radiator, radiator fan, thermostat, etc.  regardless of whether the outside temperature is 10, 20, 30 or 40 degrees C.   The fact that SA is warmer, can therefore have no, or little impact.   The lower "w" number is a different story though.

If you look at the chart you posted, that seems to be clear as well.

[Famous Fanus]

If that's the case why did Stephan Peterhansel said they strugled with the puegeots engine temperature on the Dakar yesterday because of the heat of yesterday?

[Az]

The fact that SA is warmer, can therefore have no, or little impact.

Easy to test.. monitor your temps as you let you bike idle for 15min on a nice frosty morning and then again at midday on a 30+ day.

[TheBear]

If that's the case why did Stephan Peterhansel said they strugled with the puegeots engine temperature on the Dakar yesterday because of the heat of yesterday?

I don't know.   This is why I am asking.   My guess is that Peterhansel was hammering the crap out of the car,  possibly exceeding what the cooling system could handle in that heat and the engine I am talking about in my question is not in a race car.  It is in a standard vehicle doing duty on a daily commute.

[TheBear]

The fact that SA is warmer, can therefore have no, or little impact.

Easy to test.. monitor your temps as you let you bike idle for 15min on a nice frosty morning and then again at midday on a 30+ day.

Idle would not be a true test since a large amount of cooling is lost,  not so?   Even then, I am asking: "if my engine is running at 80 degrees, or even 100, or 120, how does an ambient temperature of 40 have any impact on the oil inside that engine?"

[Az]

The fact that SA is warmer, can therefore have no, or little impact.

Easy to test.. monitor your temps as you let you bike idle for 15min on a nice frosty morning and then again at midday on a 30+ day.

Idle would not be a true test since a large amount of cooling is lost,  not so?   Even then, I am asking: "if my engine is running at 80 degrees, or even 100, or 120, how does an ambient temperature of 40 have any impact on the oil inside that engine?"

But all you'd want to see is the differential? running, idling would make no diffs to the effects of ambiant temp, which is what you'd be testing.

[TheBear]

The fact that SA is warmer, can therefore have no, or little impact.

Easy to test.. monitor your temps as you let you bike idle for 15min on a nice frosty morning and then again at midday on a 30+ day.

Idle would not be a true test since a large amount of cooling is lost,  not so?   Even then, I am asking: "if my engine is running at 80 degrees, or even 100, or 120, how does an ambient temperature of 40 have any impact on the oil inside that engine?"

But all you'd want to see is the differential? running, idling would make no diffs to the effects of ambiant temp, which is what you'd be testing.

The initial discussion started because this was said by a poster:

" Remember, these oil specs are set for Europe (colder climate). South Africa is a much hotter place to live, so we may need the thicker oil as I said"


So, to cut out all the middle waffle, please let me see if the above statement is correct and if so (or not so) why?

 

[AlanDoyle]

Ok, lets look at it like this.

 An engine that is water cooled for example.................. yes, it runs at about 90 degrees C (water temperature). But that is only cooling the cylinder head and part of the cylinder. What about the temperature behind the pistons where the oil is sprayed from the big end bearing to lubricate and keep the pistons cooler, ambient temperature definately has an effect on the oil running temperature. The water does not cool the oil completely as oil is very slow to cool in this way, the air flowing around the engine sump and casings does this. That's why some engines that run really hot have external oil coolers fitted.  

[TheBear]

Ok, lets look at it like this.

 An engine that is water cooled for example.................. yes, it runs at about 90 degrees C (water temperature). But that is only cooling the cylinder head and part of the cylinder. What about the temperature behind the pistons where the oil is sprayed from the big end bearing to lubricate and keep the pistons cooler, ambient temperature definately has an effect on the oil running temperature. The water does not cool the oil completely as oil is very slow to cool in this way, the air flowing around the engine sump and casings does this. That's why some engines that run really hot have external oil coolers fitted.  

Pity you ended your post with  

It sort of kills the credibility of your response.

I Googled a bit and must say,  I way prefer the Google explanation.

[AlanDoyle]

Hi Bear, The pot was not about the credibility of my response, but rather meaning that this subject is stirring up the pot.

[TheBear]

Hi Bear, The pot was not about the credibility of my response, but rather meaning that this subject is stirring up the pot.

 

[lecap]

Ok, lets look at it like this.

 An engine that is water cooled for example.................. yes, it runs at about 90 degrees C (water temperature). But that is only cooling the cylinder head and part of the cylinder. What about the temperature behind the pistons where the oil is sprayed from the big end bearing to lubricate and keep the pistons cooler, ambient temperature definately has an effect on the oil running temperature. The water does not cool the oil completely as oil is very slow to cool in this way, the air flowing around the engine sump and casings does this. That's why some engines that run really hot have external oil coolers fitted. 

There is only one part of a piston engine which is always oil cooled: The Piston.

There is NOTHING to cool except your cylinder, cylinder head and piston. These three components surround the combustion chamber where the heat is coming from.

In a modern liquid cooled engine you do have a lot of heat transfer between the oil and the coolant happening in the cylinder head. To help with emissions  and to shorten warm up cycles and to be able to extend service intervals you find coolant - oil heat exchangers, even on bikes. (The BMW F800 is one example.)

AlanD the chart you have posted is that for air or watercooled bikes?

Hi Chris, that was just an example of how temperature effects oil viscosity's. The point I was making is that it is so hot here in SA so it makes sense to use a slightly thicker oil here. These specs on these german bikes are for European countries, much colder than SA.

Alan, it has been mentioned a few times and yet it comes up again.  Please help me understand.  An engine (any engine for the sake of the example) runs at 85 degrees C.  It will run at that due to radiator, radiator fan, thermostat, etc.  regardless of whether the outside temperature is 10, 20, 30 or 40 degrees C.   The fact that SA is warmer, can therefore have no, or little impact.   The lower "w" number is a different story though.

If you look at the chart you posted, that seems to be clear as well.

I think I mentioned it before: SA is NOT hotter than most parts of Europe (besides Scandinavia and the British Isles) looking at day time highs. It might be hotter for a longer time of the year and a lot of Europe is definitely colder in winter (when you don't ride in Europe).

[DavidMorrisXp]

After a recent bad experience with my car and carbonisation in part due to traffic congestion and long service intervals, I have decided to have my bike serviced more frequently.  I am hoping the more frequent oil changes will maintain the engine on the bike longer and I will not experience as much problems with the clutch and/or power loss later on