Fitting a larger aftermarket oil cooler?

[sp838]

Theoretically speaking, good idea or not? I was wondering if it would 1) mean you could have a larger oil capacity and 2) larger cooling surface area, 3) and most importantly, get a tricker looking oil cooler (just kidding, purity-trolls. calm down now...)

 

Has anyone here done it? Am I mistaken about the validity of ideas 1 and 2?

[Jan Hubert]

As far as i know, oil should be too hot nor too cold. So, it depends on where you live also. I have an oiltemperature gauge and it always surprises me how long it takes before the 80-90 degrees Celsius is reached. On a hot summer day comming with city traffic it rises up to near 100. Using Eni full synthetic oil.

[sp838]

Thinking about it further, a larger cooler wouldn't help with oil capacity since capacity is determined by the volume of the sump... So idea 1 is not valid. Better cooling would still be a good thing to try for, esp. as Jan says with regard to begin stuck in slow traffic.

[Jan Hubert]

I dont have an oilcooler and the original sump in place.

[GuzziMoto]

There should be a thermostat in the oil system, so that oil does not go through the cooler unless it is hot. So a larger oil cooler should not be an issue.

I doubt it would actually help for most people. Unless you have over heating issues what good would a bigger oil cooler do?

But, it should not be a problem to do.

If you do something like this I would consider adding a fan with it. If you are stuck in traffic a bigger oil cooler isn't likely to help much if there is no air flow through it. A fan might help.

A bigger oil cooler does add more capacity, but often the oil in the cooler does not get changed during an oil change, so it is a trade off.

[sp838]

Jan, why don't you have an oil cooler? Did you remove it?

 

The fan idea is a good one, I have friends who ride enduros who have basically zip tied computer fans to their water radiators, some with a little thermostat, some with a manually operated switch to turn the fan on...

[docc]

Jan, why don't you have an oil cooler? Did you remove it?

 

The fan idea is a good one, I have friends who ride enduros who have basically zip tied computer fans to their water radiators, some with a little thermostat, some with a manually operated switch to turn the fan on...

The more I play bass guitar, the more I wish I had fans.

 

even just one . . .

[GuzziMoto]

Fans are nice, but groupies are better......

[Jan Hubert]

Jan, why don't you have an oil cooler? Did you remove it?

 

The fan idea is a good one, I have friends who ride enduros who have basically zip tied computer fans to their water radiators, some with a little thermostat, some with a manually operated switch to turn the fan on...

The bike is a '96 sport. No cooler was provided by factory.

[Lucky Phil]

Why would you want a larger oil cooler? is there some empirical evidence one is needed? or is it the " I just need to change something" deal.

Ciao 

[MartyNZ]

Just like GuzziMoto said, if you fit a larger oil cooler, then in normal operation, not much will happen.

The V11 thermostatic oil temperature regulator would be operating the same as before, and it will shut off oil flow through the cooler if the oil is below 71 degC. A larger oil cooler will not cool more than the stock oil cooler unless you operate the engine for extended periods with the thermostat valve fully open, and the oil temp does not stabilise at safe levels.

The regulator begins to open at 71 degC, and is fully open at 85-90 degC. You need better oil cooling if your oil is getting into the range of 160-180 degC (and you should be using fully synthetic oil at those temperatures). A temperature indicating dipstick will tell you how hot your oil is.

As Jan said, oil too cold and too hot are both bad. If your oil is too cool, then the actions of some oil additives is inhibited, and condensation makes sludge form, as well as the obvious engine running clearances. Too hot and lubrication and cooling deteriotates and the oil forms varnish and carbon.

So if you WANT to fit a bigger oil cooler, then you won't do any harm, as it can't cool below 71 degC.

To decide if you NEED to fit a bigger cooler, then you need to collect some data.

[sp838]

Thanks for this explanation Marty, makes sense. I guess I was confusing the action of engine oil and the performance of the oil cooler, with that of the liquid coolant of a liquid cooled engine and its radiator.

 

In thinking about it, I also realize that the oil cooler's volume and surface area are probably perfectly calculated in proportion to the volume of engine oil, so changing its size wouldn't be of much if any benefit, unlike bigger water radiators which are better for water cooled bikes. Only benefit might be -faster- cooling down to the 71°C - 90°C temp. range, which could be an improvement for city riding in the summer. Dunno about yours but my V11 hates being in slow traffic.

[GuzziMoto]

I do think that a larger oil cooler would increase the cooling capacity of the motor. And the thermostat would allow you to run a larger cooler without over cooling like other bikes. But in slow traffic, where you are most likely to run into over heating issues, the larger oil cooler probably would not help as much as a fan that blows air through the oil cooler. It is the same as water cooled motors. They use a fan for slow speed situations to help cooling. Bigger radiators increase cooling capacity but have less benefit in slow speed situations.

If you dramatically increase the power output of your motor you are also increasing the heat output of your motor. If you ride in slow speed situations a lot you also may benefit from a larger oil cooler and/or a fan. Or not. It is likely not needed, but it can't hurt. If you want to know if it would help, track your oil temp.

But I would not over estimate the engineering that went into your Guzzi. They likely grabbed the oil cooler that was handy, the one that fit in the location the stylist wanted it in. I seriously doubt there was any real "engineering" that went into it. It is a Guzzi.

[sp838]

I would not over estimate the engineering that went into your Guzzi. They likely grabbed the oil cooler that was handy, the one that fit in the location the stylist wanted it in. I seriously doubt there was any real "engineering" that went into it. It is a Guzzi.

 

hahahaha

 

If you dramatically increase the power output of your motor you are also increasing the heat output of your motor.

 

I don't know how dramatic the power output of the motor is now that I've installed the higher compression pistons etc., haven't done a dyno session yet (really should do it soon) but it's presumably gonna be something measurable, so maybe it isn't such a crazy idea... Not a top priority perhaps, but I'm going to investigate further. Earl's performance makes a whole range of oil cooler sizes and shapes, lines and adaptors, and hanging brackets are easy enough to fab up.

 

Thanks everyone!

[Kiwi_Roy]

I think the oil would overheat only in traffic with low air flow over the radiator.

What would work better, a larger radiator with low air flow or adding a small computer fan behind the existing one?

 

A small thermostat on the return line set to about the same setting as the existing thermostat would cut the fan in or if it ran 24/7 the existing thermostat would only let oil in when it gets overheated.