KZ650 Oil Cooler Adaptor

An oil cooler certainly won't hurt, especially in hot conditions. But many things have changed since the 70s and 80s.

Modern synthetic oil can maintain a better viscosity (and for longer) than the mineral oil these bikes were designed with. A 10W50 oil will have the same viscosity as a 10W40 when cold, but will stay more viscous once heated, and will handle high temperatures better. With the better additives we use now they won't leave much sludge when run hot as old oil does either.

If you're spending time sitting in traffic in hot weather, it's probably worthwhile. If you're always on the move I don't see it being necessary, especially if using modern oils. If you have a heavily modified bike, that's a different story.

 

I have been riding my 831cc motor without a oil cooler for years but I am switching to a cooler this year as I know it runs hot if I hit traffic.

Summers here can hit 95F so it is needed, my liners are .080" the same as a 900 bored to 1015. My barrels are a bit thin due to the larger liner so that is a issue for needing a oil cooler as well to keep the liner round and in place.

I would like the bore job to last so I think its in my best interest to run this engine with a oil cooler.

I am also building a 1197 street motor so that one is also getting a oil cooler.

Thank you for all information!

adding a temp gauge, is maybe smart for monitor the temp?

 

sorry for spaning your thread… Will close my mouth

I don't know how effective of accurate those type of temperature gauges are, plus you have to look down at it while riding - not a fan of doing that at all.
If your concerned about oil temp then there are all kinds of digital temperature gauges out there you can add to your dash/handlebars that would run off a pressure plug and be way more accurate.
Koso brand is one that comes to mind.



 

I have been running a 1993 ZR1100 oil cooler on my KZ650 for about 8 years now, using the Klasmo fitting kit. I have an aftermarket gauge on the oil filler opening to monitor the temp. I have about 40k miles of practical riding with this setup in all types of weather conditions. I have found that my KZ650 SR does NOT run cooler in temperature with the oil cooler installed. The machine runs steady at temp, and has not overheated. The volume of the oil system is now larger by a bit over 1 quart. Practically, the oil does not look as black/burned up when I change the oil. I use to change the oil at 2500 miles, but now I can run longer before I need to device the oil.

I have seen several different ways to plumb the system, with some spirited insistence that one way is better than the other. I don't know, but I am comfortable with the look and improved performance of my system. I was surprised that the temp did not come down, but not loosing any sleep over the finding.

The oil cooler is not to cool the engine.       The oil cooler is mostly to prevent oil from boiling and losing its lubricity....more of safety device.....   and does not hurt because in a motorcycle oil not only lubricates the engine, but also the transmission, and additionally cools the wet clutch..only area where the oil is used as cooling media.


............the oil mostly dissipates heat generate by the clutch. .......and remember, even liquid cooled motorcycles have oil cooler.        

....it is better to have it than not to.........just like an automatic transmission fluid cooler.     Helps longevity.