Ninja 250 Engine Oil Cooler

[DaBlue1]

Over the past year I've had people ask me about this and where they can get one. Someone else on the forum has also shown one but didn't give a lot of details. Even though there are a couple of other threads on 2 other Ninja 250 forums, I've been asked to put up a thread here about what I've found out and think about this engine oil cooler. This thread may be a little long but should be informative.

Back in June of 2010 myself and Spooph were looking into a engine oil cooler that we had seen on a Ninja of a Newninja member (Eric Walker), who happens to be a designer and race sponsor in Thailand. He has also worked with Kawasaki Thailand on a few development things. he was also one of the first to put a Ninja 650 rear wheel on the 250 Ninja. After more than a few rounds of e-mails, the coolers were brought to us here in the States when Eric came on a business trip.

This is from one of my other threads.

11-27-2010

OK, It finally arrived and I got a chance to install my engine oil cooler. I have to say it it really nice, quality and appearance wise and both hoses are much bigger than the stock oil hose (which should help improve flow).

The install was pretty easy. Of course if you've done any maintenance on the bike, you'll know taking off the fairings can take a good amount of time. Once the fairings are off, it is easy from there.

I did a couple of other things while I had the fairings off as well, so my install time was a a little long, but if I had to give a time on just installing the cooler by itself, I would say about 20 -30 minutes for someone with moderate mechanical skills.

One thing I did before install was, take off the hoses on the cooler, blew compressed air through it to make sure there was not metal debris inside. Then I put one hose back on and slowly put a little engine oil in the cooler, put the hose back on, then assembled it the the bike. Checked the copper banjo bolt gaskets, torqued all the bolts, checked for leaks, let it warm up at idle real well, took it for a nice spin down the road, rechecked for leaks.

The temp outside was in the low 50's, so a real test of it's cooling efficiency will have to wait for a much warmer day. Other than that..I like it!

I have all the contact information for anyone interested in the engine oil cooler. The price is about $87.00 USD or 3,000 Baht (Thai Currency). Currently, as far as I know there are only two of these coolers in the United States.

*Update* 11-30-10

Today the temp was in the mid 70's, so I took the bike out on an extended ride at hwy speeds. There was no performance loss. In fact the bike seemed to run very good, but I think the ambient temp had a lot to do with that. Immediately after the ride I rechecked the cooler. It was very warm but not hot enough to touch, so there is some heat / cooler air exchange happening . The engine was hot as it normally would be. The next thing is to get an actual temp gauge reading of the oil. For someone who rides in a hotter climate, I think this cooler could help scrub more than a few degrees off of the oil temperature.

Description
This is a bolt on. It is attached on to the bottom of the existing radiator using the stock bolts and bracket the comes with the cooler. The stock Ninja has only a small hose that goes between the oil pump on the left side of the crankcase to the top of the upper cylinder on the right side of the engine behind the exhaust. This Oil Cooler replaces that hose. Normally the engine oil is cooled by air passing around the engine and the fins located on the bottom of the crankcase.

The ideal operating range for engine oil is around 180°F - 200°F, however the engine radiator coolant can be hotter than this (between 200 & 220°F). If your radiator fan ever comes on, the optimum engine operation temp has been exceeded and more than likely the engine oil is hotter as well.

For this mod, there is no extra oil added or need. The capacity of the cooler is only 100cc, however the larger size hoses along with the cooler provide more surface area for air to cool, and better oil flow thus cooling the oil. Combine this with a good synthetic oil and the cooling efficiency is enhanced. Talking to the developer, these coolers are having a good amount of success on the Thailand 250 Ninja Race circuit.

Lowering the temperature of engine oil has many advantages, especially in air-cooled motors. Oil has a lifespan of a few thousand miles (especially in the high revving Ninja). When the motor exceeds normal operating temperature, the engine oil breaks down quicker. Changing the oil often, helps keep the oils lubricating ability and slows the breakdown process a little. The oil cooler system can maintain the quality of oil for longer periods of time by lowering the working temperature of the oil and possibly extending the life of the engine and transmission.

Definitely a mod that has positive long term implications.

How effective is the oil cooler?
According to Eric the oil cooler is only showing it's efficiency when bike is moving and there is sufficient airflow through the fins. When standing still it does nothing. It's a supplement cooling aid to prolong the efficiency of motor oil.
The FI Ninjas do have a temp gauge.The needle will show 2/5 with the oil cooler installed and 3/5 when not on the scale. The cooled oil is directed directly onto the cylinder head. Cooling the head from above.

Cost
At the time these were purchased the price was about $87.00 plus S&H.

Are there other coolers available?
Yes. One is available from http://asiaproducts-factory.com/prod...d=1&model_id=3
I'm sure if asked nicely, one of our distributors or Asian connections can source and ship others.

[dubojr1]

I think this is a great idea. I'm wondering if I could find another cooler available from a different motorcycle/ATV that could be fabricated easily to the lil ninjette. Off to eBay I go.

[dubojr1]

No pun intended but does size matter?

[DaBlue1]

Originally Posted by dubojr1

No pun intended but does size matter?

I believe it does. Most coolers are sized based on engine displacement. You should be able to find some 150 or 250cc scooter coolers that may work. Also there is mounting space, hose diameter, and oil travel distance, flow impedance and oil pressure that become concerns. Here may be one to look into. http://www.scooterpartsplace.com/150...il-cooler.aspx

Good luck.

[dubojr1]

Yeah I was kinda thinking the same thing. I think it would also depend on the machine it originates from too on whether or not it was air or water cooled. I would think that an air cooled engine would have a larger oil cooler on it.

[DaBlue1]

Originally Posted by dubojr1

Yeah I was kinda thinking the same thing. I think it would also depend on the machine it originates from too on whether or not it was air or water cooled. I would think that an air cooled engine would have a larger oil cooler on it.

Not necessarily. You have to take in to account engine oil capacity as well.

[dubojr1]

So now I'm reading other information out on the web. Some are saying that unless you run a thermostat control on the cooler then your oil during the winter months could actually run too cold.

Thoughts / experience?

[DaBlue1]

Originally Posted by dubojr1

So now I'm reading other information out on the web. Some are saying that unless you run a thermostat control on the cooler then your oil during the winter months could actually run too cold.

Thoughts / experience?

Depends on the ambient temp. I don't ride in freezing weather, so it's not a problem for me. I've still had the fan come on once in mid 50 degree temps. Because the cooler is so small, it's not a lot of cooling surface but enough. I think Spooph had his on for a short time in a Colorado winter. He did say he took his off because of over cooling. Unlike the radiator, the oil cooler could be blocked/covered to prevent airflow thru the cooling fins if you did not want to remove it for winter riding. I always recommend to people wanting to block off the radiator in winter, not to do so but instead block the cold air flow around the engine by blocking off the lower half of the fairing below the radiator. Remember part of the engine cooling is air also.

[dubojr1]

Well I think my coldest riding day this past year was 28 degree's. Of course Florida doesn't see many of those days so I'm sure I could make some kind of block for it.

The Thermobob is supposed to fix the over-cooling of the engine coolant on those same cooler days so that will be in my future too. It's kinda weird that I'm trying to get the bike to run higher (normal) temps for the coolant and I'm also looking to lower the oil temps.

[DaBlue1]

Originally Posted by dubojr1

...The Thermobob is supposed to fix the over-cooling of the engine coolant on those same cooler days so that will be in my future too.

The only problem I see with the Thermo-bob on our bikes is space. Theres just not enough space between the radiator cap and the radiator. The thermo bob housing would have to re routed and have some kind of flex house and sit lower than the radiator cap.

[Alex]

Great thread.

[flurbadurba]

want.

[dubojr1]

Originally Posted by DaBlue1

The only problem I see with the Thermo-bob on our bikes is space. Theres just not enough space between the radiator cap and the radiator. The thermo bob housing would have to re routed and have some kind of flex house and sit lower than the radiator cap.

Hmm... I was thinking the Thermobob install would be very similar to the pregen which has already been done.



Here's what I decided that looked best for the cooler from ebay. I'm searching for the proper length lines that bolt to cooler and have the banjo on the opposite end. You by chance know how long those lines need to be?

[DaBlue1]

I asked exploring/carolina about the lengths for the Thermobob he did. So I have those. I'll have to measure the hose length for the oil cooler. I do know that the inside diameter of the cooler hose is about 3x bigger than the stock hose.

[dubojr1]

Originally Posted by DaBlue1

I asked exploring/carolina about the lengths for the Thermobob he did. So I have those. I'll have to measure the hose length for the oil cooler. I do know that the inside diameter of the cooler hose is about 3x bigger than the stock hose.

Do you know an approximate diameter of the inside then. The hoses will have to come from another machine as the the lines for this particular cooler are not anywhere near what would be needed.

[DaBlue1]

Originally Posted by dubojr1

Do you know an approximate diameter of the inside then. The hoses will have to come from another machine as the the lines for this particular cooler are not anywhere near what would be needed.

I don't know the inside diameter of the stock hose or new ones. That one will require some forensics. I do know the new hose are custom made. But here is what I do have...

The stock oil hose length is 10.5 in.
The OPU-cooler hose is approx 8 in.
The cooler-head hose is approx 9 in.
The cooler is 7.5 in long x 1.5 in wide
The mount plate is 1 in. high

ThermoBob dimensions;

The overall length of the Thermo-Bob unit is 3.5".
The ThermoBob length is 1.9" not including the nipples.

The overall length of the Tee/Bypass is 2". The Tee/Bypass is .8" not including the nipples.
According to exploring/carolina, WattMan has an alternative ThermoBob routing, if the PreGen setup will not work on the 08 and later bikes. You'd have to see what he has.

[dubojr1]

Thanks a ton man. This is all good information!

The cooler I found was from a Suzuki GS500. It's dimensions "appear" close to one you have but the cost looks to be around $20-25 for a used one. A small radiator mount bracket can easily be made from aluminum and the 500's cooler can be mounted up in a very similar fashion to your. This means the hose lengths I'll need to look for should be pretty close to your coolers hose lengths.

Back to eBay I go.

Originally Posted by DaBlue1

I don't know the inside diameter of the stock hose or new ones. That one will require some forensics. I do know the new hose are custom made. But here is what I do have...

The stock oil hose length is 10.5 in.
The OPU-cooler hose is approx 8 in.
The cooler-head hose is approx 9 in.
The cooler is 7.5 in long x 1.5 in wide
The mount plate is 1 in. high

ThermoBob dimensions;

The overall length of the Thermo-Bob unit is 3.5".
The ThermoBob length is 1.9" not including the nipples.

The overall length of the Tee/Bypass is 2". The Tee/Bypass is .8" not including the nipples.
According to exploring/carolina, WattMan has an alternative ThermoBob routing, if the PreGen setup will not work on the 08 and later bikes. You'd have to see what he has.

[dubojr1]

Here's another question. Should a Thermobob be done first? Our bikes coolant tends to run a bit on the lower temp side which I'm sure helps the oil temp stay down too. Once a thermobob has been done then the coolant temp will be more controlled but it will also run at a little bit higher temp. This would also raise the oil temp right?

[GateKeeper]

This is very interesting, I suppose one could use just about any oil cooler, this one if from my GS750E, I will have to see how it would be to try and fit it on the Ninja....

before painting it



after painting it

[dubojr1]

Oh wow. That one looks nice too. Easier maybe too because it only needs banjo bolts on both ends.

[cuong-nutz]

Debating.... which one to go with... suggestions?

http://www.ebay.com/itm/Dirt-pit-bik...40144d&vxp=mtr

http://www.ebay.com/itm/Dirt-Pit-bik...527f17&vxp=mtr

[DaBlue1]

Originally Posted by cuong-nutz

Debating.... which one to go with... suggestions?

I'd go with the one with banjo bolts and braided hose, provided the banjo bolts were the correct size. You definitely would need to make a mounting bracket.

[mgentz]

Wasn't there a series if posts regarding this? If I recall correctly people complained about a drop in oil pressure and not enough oil getting to the head.

[DaBlue1]

Originally Posted by mgentz

Wasn't there a series if posts regarding this? If I recall correctly people complained about a drop in oil pressure and not enough oil getting to the head.

Never heard or read that. As far as I know there were only two coolers (like mine) personally bought to the States. If you find something post it up.

[DmbShn41]

Sorry to dig up from the archives, but any updates on this? Is it a worthwhile upgrade that lasts? Or did anyone have massive failures related to this? I'm looking to do this for the oil longevity as I typically only see enough miles to do one oil change a season, but would feel better knowing that within those miles, the oil is kept in good condition. Thanks~

[Ghostt]

I did a similar setup on my PreGen, Here's the write-up,

to cool, or not to cool, that is the question....

[DaBlue1]

Originally Posted by DmbShn41

Sorry to dig up from the archives, but any updates on this? Is it a worthwhile upgrade that lasts? Or did anyone have massive failures related to this? I'm looking to do this for the oil longevity as I typically only see enough miles to do one oil change a season, but would feel better knowing that within those miles, the oil is kept in good condition. Thanks~

Over 4 years and 26k miles and no problems. How many miles are you doing a season? I would say if you are only changing your oil once a season, you really don't need an oil cooler. My guess is your not even stressing the oil to long extended periods of heat and high rpms.

Even with my oil cooler I still change the oil frequently. Good oil is cheap insurance for a longer running engine.

[DmbShn41]

Originally Posted by DaBlue1

Over 4 years and 26k miles and no problems. How many miles are you doing a season? I would say if you are only changing your oil once a season, you really don't need an oil cooler. My guess is your not even stressing the oil to long extended periods of heat and high rpms.

Even with my oil cooler I still change the oil frequently. Good oil is cheap insurance for a longer running engine.

I'm running between 3-5k miles a season, depending on the Ohio weather patterns....I always start the season with fresh oil, and then depending on how long I can go, maybe hit another one close to end of season, then change it at beginning of next. Oil cooler would be for the purpose of insurance with the oil. I ride most of my miles on the highway, so high RPMs for extended periods of times. Figured that with a $40 or so investment, couldn't be a bad thing. Was just wondering what the longevity of this was. Thanks for the response.

[quarterliter]

Originally Posted by Ghostt

I did a similar setup on my PreGen, Here's the write-up,

to cool, or not to cool, that is the question....

156F is too cold for oil. That is not up to operating temp, and because of this your oil is too thick. Oil is rated hot at 212F and running it cooler than that is not good. Hotter is better than too cool. SRT will state that 300F oil temps are nothing to worry about with penziol ultra, a high quality GRP III oil. Unless you are seeing 300+ oil temps, an oil cooler is not necessary. An oil cooler will reduce flow in an engine as well. More distance the oil has to travel which equates to more fluid drag. Also with oil that cool, contaminants such as gasoline, and water will not evaporate off as effectively.

Moral of the story is you should use a good oil such as 5w40 rotella t6 and change it every 3000 or so.

[jkv45]

All oil, synthetic or convention, is designed to run at 212F - that's the temp they use to get the higher rating. There may be instances where an engine could exceed that, but with a water-cooled engine it wouldn't be by much in most conditions.

With oil, thicker and colder are NOT better. An oil cooler will extend warm-up time also, which is also not an advantage.

If you are concerned about maximum protection, move up to an ester-based synthetic oil (Group V) like Redline or Motul which can withstand extreme heat and pressure that even a Group III synthetic like Rotella T6 can't. But if you are getting into that range, you most likely have bigger problems.

[Somchai]

The oil temperatur of my Ninja (2011) with the oil cooler here in an outside temperature of around 100 F is between 180 F and 200 F (rpm around 10500 all the time) and since I use Motul 300V Ester core racing oil there is no problem until it reaches 300 F.
With all modern oils you should have no problems until the temperature is starting to move higher than 250 F, while racing oils are good up to 300 degrees in F.
The lowest temperature from where you should rev your engine to high rpm is 175 degree in F.

[Ghostt]

@quarterliter @jkv45 @Somchai

If you look again at my write-up, you will see that it's not the actual oil temperature, the temperature gauge I have is an oil cap, so it doesn't actually sit in the oil itself, it's in the clutch cover. It did read cooler with the oil cooler, so it's all relative.

My ride report on the oil cooler, with the ambient temperature pretty much the same as yesterday's, and rode the exact same route, and style.

Without the oil cooler, oil temperature was 80℃(176℉), with oil cooler 66℃(151℉).

I know this sounds low, and I know it is, since the oil temperature gauge is just kinda mounted in the clutch cover, and your right. But it's all relative, and there is a definite temperature drop.

Bottom line is I'm happy with it, and cooler oil is always a good thing.

[Somchai]

Originally Posted by Ghostt

@quarterliter @jkv45 @Somchai

If you look again at my write-up, you will see that it's not the actual oil temperature, the temperature gauge I have is an oil cap, so it doesn't actually sit in the oil itself, it's in the clutch cover. It did read cooler with the oil cooler, so it's all relative.

I messure the temperature direct in the oil main stream after the oil cooler.

[quarterliter]

Originally Posted by Ghostt

@quarterliter @jkv45 @Somchai

If you look again at my write-up, you will see that it's not the actual oil temperature, the temperature gauge I have is an oil cap, so it doesn't actually sit in the oil itself, it's in the clutch cover. It did read cooler with the oil cooler, so it's all relative.

If it isn't in the actual oil, I would argue that your data is useless then and that some other method should be used to check oil temp. It may give you some idea of the effect of the cooler, but to know if you need it you need to get actual oil temp.

[InvisiBill]

Originally Posted by quarterliter

Oil is rated hot at 212F and running it cooler than that is not good. Hotter is better than too cool. SRT will state that 300F oil temps are nothing to worry about with penziol ultra, a high quality GRP III oil. Unless you are seeing 300+ oil temps, an oil cooler is not necessary. An oil cooler will reduce flow in an engine as well. More distance the oil has to travel which equates to more fluid drag. Also with oil that cool, contaminants such as gasoline, and water will not evaporate off as effectively.

Moral of the story is you should use a good oil such as 5w40 rotella t6 and change it every 3000 or so.

Originally Posted by jkv45

All oil, synthetic or convention, is designed to run at 212F - that's the temp they use to get the higher rating. There may be instances where an engine could exceed that, but with a water-cooled engine it wouldn't be by much in most conditions.

With oil, thicker and colder are NOT better. An oil cooler will extend warm-up time also, which is also not an advantage.

If you are concerned about maximum protection, move up to an ester-based synthetic oil (Group V) like Redline or Motul which can withstand extreme heat and pressure that even a Group III synthetic like Rotella T6 can't. But if you are getting into that range, you most likely have bigger problems.

The Thermo-Bob guy agrees with these statements too.
http://www.watt-man.com/uploads/TB_FAQ.pdf

"Why a 195°F thermostat instead of a 160°?"
Because hotter is better until it causes items to decrease in life. The KLR oil is notoriously cold in the winter, hotter only helps get more heat into the oil which helps get rid of contaminants that enter the oil. I’ve dealt with a few engine designers over the years and they’ve said if mileage and engine life was their primary design goal, they’d probably use a 220° or 230°F thermostat. Current materials / design seem to be around 195°-210°F on the exit side of the engine, and for the cars that actually have the thermostat on the inlet side of the engine controlling the inlet temperature, they control at 180°-195°F, which results in very similar exit temps for both designs.

"I thought hotter was worse"
I hear this occasionally from the over-generalizers. They get on a "hotter is worse" thread because we all know that 300°F is worse than 250°F. And based on experience, 250° is worse than 230°. But is 160° worse than 140°? No, it's better. Engines are designed to run in a certain operating range... 140° stinks, 150° is better, 160° is better still, etc. You want to be in that 190°-220° range all year to keep clearances right and to keep your oil free of water.

Bottom Line – This hasn’t raised peak temps at all – but have raised minimum temps when you're riding and it's below 80°F outside. Even here in the desert, that's the majority of my year. In a lot of places, that's the entire year.

I personally think it's more advantageous to upgrade the cooling system with something like a Thermo-Bob to add a bypass loop. That way, the coolant is constantly circulating through the engine staying a consistent temperature. When it gets too hot, the thermostat opens and allows coolant through the radiator to dump some heat. When it cools down again, it returns to just flowing through the engine.

By comparison, the stock setup is a single loop. When the thermostat is closed, it essentially blocks flow of all the coolant. That makes it harder for the heat of the engine to get to the thermostat to cause it to open when the engine gets warm. When it does open, the cold coolant that's been stuck in the radiator rushes into the engine (we all know that throwing cold water on hot metal is a great idea), and in some cases will even make it through the engine cold enough to cause the thermostat to close again, causing the cycle to repeat.

With a bypass circuit, as long as your radiator is sufficient to dump as much extra heat as the engine is making, the engine should stay right around the thermostat temp, without major swings up or down. When it gets warmer, the stat opens and the radiator dumps the extra heat. When it gets cooler, the stat closes and the coolant just loops through the engine.

It's bad if your oil is too hot. But it's also bad if it's not hot enough. Being a water-cooled engine, the oil is only a secondary cooling method. I think it's more of a direct fix (as opposed to a band-aid on a symptom) to change the lame cooling system to something that will help the entire engine stay the proper temp. If everything else is in working order and your oil is still too hot, definitely add a cooler. But I don't think it's a good idea to just assume (without any data) that adding a cooler is an improvement over stock.

[wardie]

How much additional oil does the system hold with the cooler installed?

The additional oil has to have some positive affect on cooling.

[sharky nrk]

Originally Posted by wardie

How much additional oil does the system hold with the cooler installed?

The additional oil has to have some positive affect on cooling.

There is not alot of additional volume in those coolers, not sure exactly how much in this application but I know that when installing at transmission cooler on different vehicles of larger sizes, it still was not that much additional volume.

I would venture a guess to say we are talking less than a 1/4 of a quart, maybe not even a 1/10th on a small cooler like the ones here. That is of course a WAG but its not going to a lot.

The additional oil volume is likely not going to hurt anything, nor is the the additional cooling from this unit in most climates. It is also not likely to benefit much unless oil temps are being pushed around 225-250F.

I would consider this on a oil/air cooled machine a lot more so than water cooled unit as well.

[InvisiBill]

Originally Posted by wardie

How much additional oil does the system hold with the cooler installed?

The additional oil has to have some positive affect on cooling.

According to the OP, the cooler had a capacity of 100cc. The Owner's Manual says the engine has an oil capacity of 1.7L from dry. That's an extra 5.9%, not counting the extra in the associated lines. With such a small total capacity (my EX500 takes over twice as much oil), I'd say that adding extra oil is generally a good thing. But as stated above, don't assume without data that doing more to cool the oil is a good thing, plus there are downsides (also mentioned above) to adding more components into the oil flow.

[DmbShn41]

All good data and definitely things to take away from this. Did not dig this up to incite a riot. Thanks all.

[spooph]

This cooler would work great for a turbo setup, or, if you live in an area where the ambient temperature is close to, or over 100F, especially if the humidity is over 60%, much like what can be experienced in the summer in Thailand or North Carolina..

However, many places in North America do not get hot and humid enough for this, for any length of time, and unless you ride your bike thousands upon thousands of miles, you will not see any benefit in either the engine or oil condition.

This cooler would be more of a risk in the northern or higher altitude states (like in CO). Here in Colorado I only say about 2 weeks a year of weather where the cooler would have helped, and almost 7 months where the cooler would have hurt my oil, so it didn't stay on my bike for very long.

The craftsmanship was immaculate however and Eric is a most delightful individual to work with!