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Discussion Starter · #1 ·
In another thread this popped up and i figured i'd start another discussion on the topic here to get some feedback and opinion.

OEM and the HRC kit/works front mount setups- Radiators run parallel, meaning we have coolant simultaneously flowing into and leaving both radiators via Y connections

Aftermarket Thermae, Durbahn, and Furick front mount setups- Radiators run in series, meaning we have flow first through top radiator then into left horizontal radiator and back into engine.

Why the difference and how much cooling capacity are we loosing by running in series?

Thoughts?

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Cooling is heat transfer and heat always move from hot to cold. The greater the temp difference , the more transfer , to some extent. Piped in series , the second radiator will be less efficient due to the lower temp coolant entering it , less temperature differential , less heat transfer. This is not saying hotter coolant loses more heat in a smaller radiator , it's just a basic , simple explanation before the penis gallery jumps in.
 

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Discussion Starter · #3 ·
Makes sense.

I guess my question would be, is the difference negligible in our application, hence why the aftermarket stuff went in series? My assumption would be that they made up the difference in cooling effectiveness, in comparison to stock, by moving the radiators forward from the stock lateral positioning.

Just want to understand the logic of the aftermarket stuff.

To be honest I never thought about it, until you brought it up. I just got the kit and installed it without giving it a thought. Its an interesting and valid point and now I'm thinking about redesigning the routing like we talked about.
 
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Also , as the coolant will moves through more slowly , it has more time to lose more heat. The front mounts have more surface area and also get more airflow than the side mounts. Cars have higher temp thermostats because a hotter motor needs less fuel , but it's not optimum for power. Cooler motors can take more fuel , more fuel , more power. Ever notice how well a bike runs until it gets up to temp ? Even on a car , you gain a little power just going to a lower temp thermostat.
 

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Discussion Starter · #6 ·
Most likely thermae system. Still runs a thermostat, right?
 

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I run distilled water with water wetter in my RC with stock side mounted radiators and fans and my average temps dropped 20 degrees Fahrenheit. My KTM 1190R has a front mounted radiator with electric fans and when I'm in bumper to bumper traffic it gets hot. I think the front mounts on the RC are cool but you should try water wetter, engine ice, or equivalent before spending the money on a conversion.
 

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really nice find, especially these days
 

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Hey guys hope all is well. My big bore motor is now complete and the only thing I need to get the bike going again is a front mount radiator setup. I have been thinking about a Thermae kit but theyh dont have any in stock and dont know when they will. Is someone thinking about designing another kit? I want to do it right the first time.
 

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Discussion Starter · #11 ·
No, I am more looking at playing with the routing for mine and making them parallel. Just need some basic hoses and connectors for the piping
 

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Good morning guys, as I did quite a bit of cooling system design work while working at Briggs Automotive I may have something of value to add to this conversation. My apologies if this has been brought up already in the other thread you mentioned @gts455 .

On all of the Mono's we ran a pair of pod mounted rads in parallel, one of which, the exhaust system side, is shown below:
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The first thing that jumps out at me with regards to the series setup shown in the first pic of this thread, is that the secondary rad looks to be of smaller capacity, which, if the rad tube size/spacing is identical in both units would make sense as the incoming coolant from the first rad would be lower temp, e.g., less heat to be dispersed.

Unless I am missing something I wouldn't think that rad setup can be run in a parallel configuration... I'm not saying it can't be done, but it does not appear that it would yield optimal results. Unless you are able to somehow adjust the rate of flow for the smaller rad you are going to end up with 2 different coolant temps on the way back into the engine.
 

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Discussion Starter · #13 ·
That's a good point. Definitely valuable insight. I'm leaving it in series for now. I mean that's how it was designed and its yielded good results from other users.
 
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The thermae setup works well. I ended up putting the thermostat back in on a stock engine track bike as it wouldn't come up to temp in the morning and playing with duct tape over the rad was a pain.

Don't over think it.

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