Oil cooler

[flynrider]

I've ridden my CB11 on dozens of 110+ days here in Phoenix. Can't avoid that if you ride everyday. I've never seen the oil temp light, but if I did, I'd be seriously concerned. The manual states that it will light at a frighteningly high temperature ( I think it was something like 340F). Most oils are already starting to break down at that temp.

I have managed to overheat the CB750 (also equipped with an oil cooler) on two occasions in the last 20 yrs. Both times involved standing still while idling for 20-30 minutes in 100+ temps. Now that I know better, I just shut it off if I'm not going to be moving for a few minutes.

[Pterodactyl_imp]

I've ridden my CB11 on dozens of 110+ days here in Phoenix. Can't avoid that if you ride everyday. I've never seen the oil temp light, but if I did, I'd be seriously concerned. The manual states that it will light at a frighteningly high temperature ( I think it was something like 340F). Most oils are already starting to break down at that temp.

I have managed to overheat the CB750 (also equipped with an oil cooler) on two occasions in the last 20 yrs. Both times involved standing still while idling for 20-30 minutes in 100+ temps. Now that I know better, I just shut it off if I'm not going to be moving for a few minutes.

Once or twice I've considered shutting down but wonder if that might lead to an initial rise in engine temperature as the oil stops circulating. On other engines, fitted with temperature gauges, I've observed this. With the CB as long as the warning light doesn't come on then I guess all is well.

Cheers.

[Cormanus]

Quote: curlyjoe said—

There is a high temp "idiot" light that comes on when the oil temp is too high. I wonder if our friends in Arizona or OZ have ever seen this come on when riding in stop and go traffic on very hot summer days?
Like others, I've ridden on some hideously hot days and the oil light has not come on. Most has been in the country but some in the city.

[Southwend]

What a crazy thread....how did that little black oil cooler work up such a discussion? It's hardly noticeable!

I guess it's not just oil threads, but oil related threads that do it...

I guess it's not just oil threads, but oil related threads that do it...
Very true mate. Oil is the "precious bodily fluid" of our bikes.





We cannot allow anyone to sap and impurify all of our precious bodily fluids. When did that come to me? Well forum decorum does not allow me to go there .

Cheers
And Jim, I'm not crazy. It's everybody else. Heeeeeeehaaaaaheeeeeeeee........

I guess it's not just oil threads, but oil related threads that do it...
Very true mate. Oil is the "precious bodily fluid" of our bikes.





We cannot allow anyone to sap and impurify all of our precious bodily fluids. When did that come to me? Well forum decorum does not allow me to go there .

Cheers
And Jim, I'm not crazy. It's everybody else. Heeeeeeehaaaaaheeeeeeeee........
wow one of my all time favorite cinema moments.

[Southwend]

At the risk of beating the dead horse, I was in my garage staring at the CB last night. For me the whole 'oil cooler thing' for me is to allow a better view of the engine. I do not want to shortchange the engine's cooling or ignore the engineering of the design. So how about this. If the oil cooler stayed in place, but was angled out say 20 degrees or so at the bottom only so it would clear the front fender on rebound. If you picture this when you are looking at the bike, it appears that it would really open up the front of the motor visually while keeping all of the design characteristics unchanged.

[Jim21680_imp]

Hmm...if I'm imagining this right, you're thinking of rotating the cooler out into a vertical position (out away from the normal frame-mounted angle)?
I think that would undoubtably draw more attention to the cooler instead of the engine, as if something was broken off or bent, etc.

It could probably be mounted to the lower fork tubes, either in front or behind the stanchions. I don't think you'll do better than that.

[Frulk_imp]

I'm only posting here because #77 is my lucky number

[Southwend]

Hmm...if I'm imagining this right, you're thinking of rotating the cooler out into a vertical position (out away from the normal frame-mounted angle)?
I think that would undoubtably draw more attention to the cooler instead of the engine, as if something was broken off or bent, etc.

It could probably be mounted to the lower fork tubes, either in front or behind the stanchions. I don't think you'll do better than that.

not rotating, not moving, just changing the angle, away from the frame at the bottom of the cooler stiil at the frame at the top of the cooler.

[dsinned_imp]

Very interesting . . .

Here's an update to twist this subject into the extreme opposite direction. Yesterday, I was in my garage with a box full of various sizes of fans and the idea of mounting one to the front of the oil cooler entered my mind. It would be easy to do, although a pusher fan would not be as beneficial as a puller (mounted "behind" the cooler). With the elongated rectangular shape of the cooler it might even be feasible to mount TWO fans side by side.

First, I'm planning to install a thermocouple sensor with a handlebar mounted temperature meter to measure the EOT at the stock cooler. The delta T across the cooler also would be of value to measure, but more complicated in favor of just the temperature at a single fixed point. Then, repeat the same measurement, under identical test conditions, with a fan mounted. This answers the question, would there be any benefit with the addition of the in lowering EOT?

I suspect there would be especially at relatively high OAT, stop and go riding conditions, or making the engine work harder riding continuously uphill for several miles at a relatively slow speed.

A good candidate for a fan - one with an integrated finger guard for added personal safety - is one made by the Italian automotive grade fan manufacturer, SPAL. They have a relatively low cost, 5.2" diameter pusher fan suitable for this application. (They have smaller sizes, but their CFM ratings are much less than the 5.2" fan.) It's a bit oversize, but should do good a job helping to further air cool the oil flowing thru the cooler on the CB1100, without causing the 12V battery and alternator to be overloaded.

I'm going to take on this project mainly to gain a better understanding of the OEM oil cooler and how it can be made to look even uglier, but more efficient, without major modifications, at the same time.

P.S. There is another recently started thread on the subject of measuring EOT, so I will resume posting my findings over there since I think we have already established the importance of keeping the oil cooler, so this thread should be considered closed.

[Noleshot_imp]

My 1980 GS1100 did not have an oil cooler, made 105hp at the crank and survived many years in TX and FL with no mechanical issues. Nobody has mentioned the richer fuel/air mixtures then as a possible means to keep the engine running cooler. Leaning the mixture out to where they are today in a 1980 engine would cause heat related failure, detonation/holed pistons very quickly. So, why not find a way to make the mixture richer, change the spark plug heat range, etc? With the modest output of the CB, that could possibly substitute for the oil cooler, not to mention the fact that metallurgy and design are now worlds better. I also like the thought of working around emissions-related gear (we don't have emissions inspections here in Florida). Besides the clear view of the front of the engine, one could again inspect plugs and exhaust openings for the proper color left by unburnt hydrocarbons.