Forced cooling

Sasa

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Today we had a conversation with @Dool about idle and higher ambient temperature and an epiphany struck my mind: why don't we force cooling the engine or the oil radatior?

We've all been stuck in traffic during a hot summer day and any air cooled engine tends to overheat in that condition. Even my stock hima used to start sputtering and die occasionally at traffic lights because the engine was way too hot. Since our engine is cooled (partially) with oil and there is an oil radiator already, the idea is to place one or more fan/fans behind the oil radiator. There are plenty of IP67 (waterproof) 12V fans out there.
The easiest way to drive it would be through a simple switch connected to the battery BUT that wouldn't be neither elegant nor precise as solution.
HOWEVER the mighty Red Box has an unused pin that has exactly that function and it's driven via the engine temperature sensor, with a custom threshold of actuation!

It should go like this: above a certain temperature the RB would close a switch connected to a 12V relay and the relay would then in turn power on the fan!
If anyone is interested, the actuation pin is #19. I'll take some measurements of the oil radiator to see possible fan candidates for the purpose!

What do you guys think?
 

RCruiser

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I REALLY Like it!
Maybe we could at the same time pursue the Larger Oil Radiator that had been discussed? I would think that having a larger 'face' of the radiator itself would perhaps give us more Fan options too.
I'll go back in the Time-Machine and search for the extra fan that I put on my 950A when I lived in Phoenix...
Bob
 

sam2019

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Great idea, how to isolate the pin 19 switch from the cable harness?
 

sam2019

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The shape of the radiator allows for 2 smaller fans to be stacked, however, will they diminish air flow when not in use? So maybe one only is better.
 

Sasa

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Great idea, how to isolate the pin 19 switch from the cable harness?
That's the trick: the original cable harness of the Hima doesn't have a #19 pin, so the port of the connector is pretty much empty. I need to find a way to insert a cable there. A roughed up, old and useless BS4 wiring harness would be ideal to experiment.

The shape of the radiator allows for 2 smaller fans to be stacked, however, will they diminish air flow when not in use? So maybe one only is better.
When not in use these computer fan would spin almost effortlessly, so I guess they would not interfere with normal air flow when not in use! Actually two stacked unit it's a good idea! I have to see what I could 3D print and source to make a fitting test!
 

sam2019

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A roughed up, old and useless BS4 wiring harness would be ideal to experiment.
almost impossible to find. that stuff goes in the trash and also: it is very rarely needed. A new one costs approx 85 euro here.
 

sam2019

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Actually most if not all harness problems are fixed by "jugaad" :alien:
Jugaaḍ (or "Jugaaṛ") is a colloquial Indo-Aryan word, which refers to a non-conventional, frugal innovation, often termed a "hack". It could also refer to an innovative fix or a simple work-around, a solution that bends the rules, or a resource that can be used in such a way.
 

Sasa

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almost impossible to find. that stuff goes in the trash and also: it is very rarely needed. A new one costs approx 85 euro here.
Not going to happen, specially with the biblical delivery times!

Actually most if not all harness problems are fixed by "jugaad" :alien:
Yeah, I'll see what I can "jugaad" when the other parts come from India and the bike goes in "overhaul" mode...
 

Dool

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Wow, a bit of movement here! I should check more often :)
Thermocouple switches are available also if connecting to pin 19 is a problem.
The current draw of the small computer fans would be low maybe no relay required, just a Fuse.
 

Sasa

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Wow, a bit of movement here! I should check more often :)
Thermocouple switches are available also if connecting to pin 19 is a problem.
The current draw of the small computer fans would be low maybe no relay required, just a Fuse.
Indeed, but I rather not overload the Red Box and risk overheating the small wonder box!
 

RCruiser

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Computer Fans? Is that what everyone is discussing here?? Surely they'd get short circuited as they're not meant to be water-proof, no?
What I had in mind was the type of fan that is standard duty for water-cooled bikes already...
(Put the computer fan on the Red Box like Sam did...)
 

Dool

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A few months back I posted up a pic and link to a Keihin plug that fits the RB, woild have been in the Alterntive ECU thread
 

Sasa

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Computer Fans? Is that what everyone is discussing here?? Surely they'd get short circuited as they're not meant to be water-proof, no?
What I had in mind was the type of fan that is standard duty for water-cooled bikes already...
(Put the computer fan on the Red Box like Sam did...)
There are some IP67 rated fans, they are meant to be submerged so they should be ok for this application
 

sam2019

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(Put the computer fan on the Red Box like Sam did...)
a peltier element, not a fan - bought it but have not installed it waiting for the heat to come back and also wanting to check if Sasa is right in thinking he solved the overheat problem by some change in the configuration.
 

RCruiser

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I didn't know that about the computer fans guys, cool.
This is what I had in mind: https://www.amazon.com/Spal-30103018-Paddle-Blade-Puller/dp/B009OBP55G It's OEM on a lot of bikes and bulletproof. The one That I had in mind is 3.75in/or 9.5cm but there may be smaller units available?
When I put another one of these on my KTM, in Phoenix with heavy traffic, it completely solved my heating issues while riding daily in the summer there... Spal 3.75.jpeg
 
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Dool

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Made in Italy !
That looks the Part;)
 

Sasa

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I didn't know that about the computer fans guys, cool.
This is what I had in mind: https://www.amazon.com/Spal-30103018-Paddle-Blade-Puller/dp/B009OBP55G It's OEM on a lot of bikes and bulletproof. The one That I had in mind is 3.75in/or 9.5cm but there may be smaller units available?
When I put another one of these on my KTM, in Phoenix with heavy traffic, it completely solved my heating issues while riding daily in the summer there... View attachment 319
These unit have excellent reputation and the 9,5cm version should fit nicely!

I checked the space available and, apart from the inlet hose coming into the radiator, there are no obstacles to mount it!

There is also an added bonus: the oil radiator is slightly angled toward the engine head: including a fan would pull air through the radiator and then direct it toward the head, improving engine cooling in two different ways!

No I've also identified the possible attaching points, I need the time to design a proper bracket. Ideally this could be 3D printed and then, once dimensions have been frozen, realized out of 2/3mm aluminum sheet and powder coated black.
Electrically I was thinking about using a three way switch: one position would disconnect the fan altogether, one would let it function on "auto" setting (controlled by the red box) and the last would be a manual override to start the fan regardless of the other conditions.
 

sam2019

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Hightech - and expensive. but who knows, if it catches on I can certainly have a few laser cut and possibly even powder coated - although that may be a big problem here.
 
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