[Black_peter]

Since your's is a 600 Kat, you may want to consider fitting a 750 oil cooler. They are a bit bigger than the 600 so it may be enough to keep it a bit cooler.

The fittings are different no? Pre 600 has banjos 750 o-ring/flange
But if you got the cooler and lines. That would work.

[hardlydangerous]

To lower engine/oil temps
use a synthetic oil.
Keep the cooler clean
go 1 plug cooler in the hotter weather
Richen the pilot mixture

last use a higher octane fuel.
I don't like going with a higher octane fuel as it costs more, waists money and performance will suffer slightly but the higher the octane the harder it will be for the engine to burn efficiently and it will slightly cool combustion temps.

Don't install a fan it will only restrict the air flow at high speeds when you need it the most and will drain and cause a larger load on the charging system at idle. the oil cooler is not like a radiator and does not need to maintain an perfect temp range for reliability. A good synthetic oil will provide all the lubrication you need regardless of the oil temps

[chinto]

The fittings are different no? Pre 600 has banjos 750 o-ring/flange
But if you got the cooler and lines. That would work.

750 cooler

http://www.bikebandit.com/houseofmotorcycles/suzuki-motorcycle-gsx750fr-katana-1994-oil-cooler/o/m6189sch280993

600 cooler

http://www.bikebandit.com/houseofmotorcycles/suzuki-motorcycle-gsx600fw-new-1994-oil-cooler/o/m6177sch260962

connections looks the same to me.

[VifferJim]

750 cooler

http://www.bikebandit.com/houseofmotorcycles/suzuki-motorcycle-gsx750fr-katana-1994-oil-cooler/o/m6189sch280993

600 cooler

http://www.bikebandit.com/houseofmotorcycles/suzuki-motorcycle-gsx600fw-new-1994-oil-cooler/o/m6177sch260962

connections looks the same to me.

Pretty sure they're the same, though, you might have to finaggle the brackets to hang it on the frame. For some reason, I remember them being a little different (??).

[chinto]

Pretty sure they're the same, though, you might have to finaggle the brackets to hang it on the frame. For some reason, I remember them being a little different (??).

as far as i know the brackets are the only thing that will need to be modified to use the 750 cooler.

[The CyberPoet]

The fittings are different no? Pre 600 has banjos 750 o-ring/flange
But if you got the cooler and lines. That would work.

98+ has both 600 & 750 having o-ring+flange design at the oil cooler-to-hose connectors, banjo-bolt connectors at the oil-pan. Unlike the pre-98's, the 98+ have the lower frame brackets welded into the frame and not as a bolt-on item. This means for a 98+, you need to use some form of adaptor bracket to support the bottom of the cooler if you put a 750 cooler on a 600.

go 1 plug cooler in the hotter weather

In plain English, that means a number higher (i.e. - if you are using a DR8ES, moving to a DR9ES) will move more heat from the combustion chamber into the heads. More details from NGK here:
NGK FAQ - Understanding Spark Plug Heat Ranges.

There are two problems with this approach.
The first is that most Kat models already call for the highest temp-transfer-rate plugs NGK offers in their class (98+ both models and pre-98 750 all use heat-range #9 plugs as stock; the only exception is the 600's which use #8 range plugs as default).
The second issue is that these high-transfer-rate plugs do not reduce how much heat the combustion builds, they just help it get out of the combustion chamber area faster (by transferring it to the heads, where the oil cools the metal!). Thus, a higher-than-called-for temp range plug can make your oil heat even faster in such a over-heating situation.

A good synthetic oil will provide all the lubrication you need regardless of the oil temps

I hate to disagree with hardlydangerous, but I do, in part from hands-on experiences (& the fact that I had the temp gauges installed in my Kats). Perhaps his experiences in Ontario are different than those I've had in Florida...

The temps in the heads, esp. in weather like we see here in the southern summers, during traffic jams and heavy stop-n-go driving can hit temps no motorcycle oil on the market is designed to deal with -- ever. If you run high speed on the interstate on a 90 degree day, and then suddenly starve the engine for fresh air in a traffic jam, the heat level at the engine will climb very fast and can easily exceed the oil's flash-temp at the heads in under 10 minutes.

While this engine is very forgiving of hot temps in general (it can easily survive running 350 degrees for hours on end), when the idle shoots from 1150 - 1350 up to above 1600+, you've hit the point that the engine simply can't cool itself adequately, and the oil has hit a temp that will start ripping the oil itself up into tiny chains that don't do the lubrication job the oil is supposed to do. Generally by the time idle reaches 1600 RPM or higher (if it's correctly set to 1250 hot in the case of the 98+ models), your oil is already above 380 - 400 degrees F at the oil pan and easily twice that at the heads.

As for cost-effective solutions, shutting off the engine when you come up on a traffic jam is still the most cost-effective one I've found

Cheers,
=-= The CyberPoet

[Jax]

Here is another solution:
Walk
Use the Bus
Car Pool
These alternatives will have a dramatic affect on your oil temperature while the bike sits nicely in the garage....

I figured everything has been said to help you out...

[zvisus]

You guys are too much.

What about attaching a peltier device to the backside of the oil cooler? It can get cold enough to freeze water, so I figure it should do wonders on the oil, no?

[The CyberPoet]

BP & I have discussed the concept of peltier devices before (embedded onto the oil pan instead, where it won't block the air-flow at the cooler and has a bigger heat-sink to draw out of)... I don't remember the complete conversation, but I think we came to the conclusion that it wouldn't work because of power-consumption vs. heat-generation rates.

Cheers,
=-= The CyberPoet

[zvisus]

I think peltier devices always generate more heat on the hot side than they take away on the cold side. i mean, they'd pretty much have to considering the amount of power they draw.

I'd also be a little worried about exposing a part of the metal pan to a significantly cold temperature. I'm not a materials engineer or anything, but wouldnt the fluctuations in hot/cold areas warp and maybe even break the oil pan?

[Black_peter]

I don't remember the complete conversation,

I do.. I thought is was a silly idea!

I think peltier devices always generate more heat on the hot side than they take away on the cold side. i mean, they'd pretty much have to considering the amount of power they draw.

They do in fact heat more then they "cool".. They also should either be run wide open or on analog control..

[thetable]

Everything I have ever read about Peltier devices says they are incredibly inefficient. Efficiency so low that you would be looking at a bigger alternator just to handle the current draw if you even wanted to cool a mildly warm engine.

[Black_peter]

Everything I have ever read about Peltier devices says they are incredibly inefficient.

They are inefficient but not based on need.. Cars are incredibly inefficient too..
If you have a very small amount of space and aren't too worried about consumption they are just the ticket.. Adding a water/oil heat exchanger would be more efficient. But the cost would be size/weight/$$.
Don't get me wrong, Peltiers on a motorcycle would be foolish IMO..

[The CyberPoet]

Adding a water/oil heat exchanger would be more efficient.

That raises an interesting point...
It might have been a misprint or misinterpretation by the authors, but a first-run magazine article when the bike first came out was saying that there was (is?) a water-shrouded oil cooler on the bandit 650's; that the cooling on them is still oil-driven.

I haven't looked at one close enough, nor have I been able to find the fiche for the Bandit 650 to verify those statements, but if it's true, you ought to be able to mod it on to the Kat with a minimum of effort.

Cheers,
=-= The CyberPoet

[Black_peter]

That is interesting. Water has a lower specific heat than oil, so it's conceivable that you could just build a box around the oil cooler. Include some heat sink and you could improve the cooling efficiency of the oil cooling. The water could act as a catalyst in transferring the heat to air.

Cyber, have you heard of heat tubes?
I might have asked you before, but a Fin was explaining it to me. It's like a reverse Sterling cycle or one of those dipping birds? A fluid is boiled on one end of the tube absorbing the heat. The vapor travels to the other end away from the heat where it condenses.
I don't know what the fluid is and I know there is some baffling involved as well.