Oil Cooler?

[mr. softie]

I know that there are quite a few used motorcycle oil coolers, some with lines, on eBay. There is also a oil cooler kit for $50 w/shipping on eBay that includes hoses and some fittings.
http://cgi.ebay.com/ebaymotors/ws/eB...3AIT&viewitem=

I have seen oil cooler lines returned to the top of the head as well, at the end of the camshaft. Don't know if this would work or not. Of course this is not the GZ motor in these pics.

[patrick_777]

Originally Posted by mr. softie

Saw this on the web, thought it was interesting. The poster (Patrick_777)??rode for a while, parked the bike for 2 minutes and took these temps with an infrared thermometer.


Looks like the hottest spot on the motor is the rear top cylinder head (besides the exhaust pipes). I agree an oil cooler would be a good addition.

HA!

The Internet is circular.

viewtopic.php?f=3&t=1024

[mr. softie]

Yes I saw that on a site that was all in some foreign language (could not even tell what language) but happened to notice in the text a reference to Patrick_777, after I had posted it, so I edited in your reference. Figured it was you. Great pic with the temps and all.

[Easy Rider]

Originally Posted by mr. softie

I agree an oil cooler would be a good addition.

OK, I'll play along.....for a while. How do you figure that an oil cooler will do much to reduce the temperature of the cylinder head.......since that is where the heat originates AND there is precious little oil flow there ??

Another consideration: Oil capacity. In order not to let the level get too low, you would have to ADD enough extra oil to fill the cooler. If much of that drained back to the sump when off, then the "proper" level might be ABOVE the sight glass.

[mr. softie]

There is a bit of oil flow from the camshaft galley as the oil lubricates the valve rockers and camshaft and then moves to the sump. The oil that lubricates the cylinder walls also has a cooling effect on the cylinders and piston. I just have a "gut" feeling that if the oil was cooler it may have a small cooling effect on the whole motor. I realize that the GZ motor was not specifically designed to be oil cooled, so the effects might be less than hoped for. I never thought the GZ motor ran all that hot till I saw Patrick_777's pic. I have read by the way that the oil should not be cooled to less than 190 degrees or so, not sure why, flow maybe?

As far as the oil level goes, without an anti back flow valve in the oil cooler supply line you are correct, the oil level in the sump would be way high at start up, which could lead to blown seals, and at the least making it impossible to check oil level. Another complication.

One of the nice things about the GZ being so simple is that it is well designed and very usable in stock form. If it ain't broke don't fix it. This is probably not such a great mod.

[Quimrider]

Originally Posted by mr. softie

I have read by the way that the oil should not be cooled to less than 190 degrees or so, not sure why, flow maybe?

If the oil is not warmed sufficiently, the following 2 desirable things wont happen:
1 Unburned gasoline that finds it way into the oil will evaporate and leave the crank case.
2 Any moisture that may have condensed in the crankcase or moisture from combustion blowby will evaporate and leave the crank case.

Where did you find the pictures of that suzuki with the oil lines going everywhere? From what I can see it doesn't look like that would be to good for the engine.

[Water Warrior 2]

Use the KISS principle. Just use a quality oil that resists thermal breakdown and enjoy the ride.

[mr. softie]

Those pics were on a GSXR site

[Water Warrior 2]

Suzuki has been air/oil cooling bikes for years. I am sure a lot of research and design went into the product before offering it to the public. The oiling system on their sport bikes is designed with oil cooling in mind. I read a couple articles about oil cooling years ago when Suzuki first brought it out and it is not just a case of adding an oil cooler. A lot of internal parts are modified to accommodate oil flow, oil quantity and oil presure as certain points in the engine.

[mr. softie]

What Water Warrior said. I agree. It is beyond the ability of us owners to out engineer the factory engineers IMHO. On the other hand there are aftermarket solutions that address weaknesses in the original design of many products, not that adding an oil cooler is doable on the GZ250. Maybe cabin fever has set in this time of year and our thinking is somewhat faulty. We can't just go for a ride so we start having all sorts of crazy ideas, such as adding oil coolers to our GZ's!