bigger radiator test
Posted February 21, 2013 - 06:02 AM
To my surprise, the rads look really good, much better than expected for the money (good welds, thick walls, thick body, but crappy cap). Also, had some good comments about their better cooling ability due to more capacity, since they are 40mm instead of the 23mm or so from OEM rads.
I always thought this bikes run a little bit too hot, specially at low speeds or hot enviroment (desert, wind form behind, hi-reving in mud or deep sand, etc) , and I think that some extra cooling would help in engine durability, reliability and efficiency., so I decided to kill my curiosity and test them.
First installed the temperature gauge right after the engine water exit.
Then run the test with OEM rads, from a totally cold engine, one day in the morning. After that, installed the CHN rads and run the same test in the afternoon, also form a totally cold engine and almost same conditions (same spot, about same ambient temperature, etc)
The test I run was very simple, home-made-non-scientific. First the “static test”: start the bike and keep it completely idle for 10 minutes (not a single gas turn). Take temp readings every 30sec the first 5 min, then every 1 min. At minute 10, turn it off and keep reading for another 5 min. After that, the “dynamic” test: run the bike hard for 3 minutes. After stopping, read the current temp and then again 1, 3 and 10 minutes after that.
After that, installed the CHN rads and hoses, and repeat the test. (kept the OEM cup)
Here, the results. (The temperature is in Celsius, sorry Fahrenheit fans)
My interpretation and oppinion:
They cool a little more (about 2 ºC) when the bike is heating up, up to a certain temperature when them both cool the same. When riding, the also cool 2-3 ºC more. When stopped, the CHN get cold faster 4ºC).
They look stronger. Couldn´t test that yet, we´ll se after a few falls if that´s true
They are heavier (rads+coolant weight like 0.5Kg more)
They don´t fit so well: the shrouds needed some hard pulling to get in place.
My general conclussion is that they seem to run a -little- better, specially when running and after stopping.
Not worth the replacement for performance reasons, but a very cheap replacement choice.
Bike: 08` WR450f with stock water pump and exhaust pipe. OEM rads non bent nor hit.
Altitude: sea level
Coolant: water with no special coolant (there´s a reason for that)
Env: 24-25 ºC, no wind, cloudy
Try them in the desert raid.
Install a fan cooler and run the test with different coolants (i think THERE will be a difference)
Install a hi-flow water pump.
Best regards, from Argentina.
Posted February 21, 2013 - 09:40 AM
Posted February 21, 2013 - 08:52 PM
Posted February 22, 2013 - 04:00 AM
One benefit that might be getting overlooked is that they hold more fluid, so if they do boil over, they will still be holding more fluid than a boiled over OEM radiator, and this might be enough to keep from causing engine damage. Just my thoughts.
Posted February 22, 2013 - 04:33 AM
Sitting and cooling is one thing, but a 15-20 minute loop with air flowing (or not flowing) might provide better ideas how the shed "overheat" and not just "normal temp heat".
Just a thought, and thanks much for doing this.
Posted February 22, 2013 - 09:49 AM
I find this very interesting , I had thought that the bigger rads would produce way lower temps.
I wonder how much more cooling would be acheived with an aftermarket/high flow waterpump combined
with the larger Chinese rads.
BTW.... nice write up .
Thanks everyone for the good feedback
I think that the hi-flow pump is the key to the difference. That´s the opinion for example, of Mauricio "Paco" Gomez, a guy from here who run 2 Dakar Rallys with a private WR450. He did it with a Boyesen Pump, OEM Rad and silicone hoses. He had ambient temperatures over 50ºC and rides at 4.000m high (water boils around 80ºc there) This year he had an Official Yamaha France YZF so he didn´t care any more about mechanic nonsense
miweber is right: 3 minutes hard run is not much. Should have run more. But what worried me most and made me try to do this was "near-static" running.At had speeds, CHN may or may not run cooler, but OEM run just fine. Hi-reving at slow speeds in sand, sliding the back wheel with no grip in mud at 5 km/h, etc., that´s what i care most...
maniac says "[color=#282828][font=helvetica, arial, sans-serif][background=rgb(252, 252, 252)] It doesn't matter how wide a radiator is while sitting still. It's all about how much surface area there is that can shed that heat to the atmosphere, and this is the same on both". The surface part is right: when moving, the bigger radiator has more surface in contact with air to radiate. Static, the surface is almost the same. but don´t forget the water volume (mass) is bigger (about 30%) So it has a bigger "heat inertia", it takes longer to heat. A little longer, as seen in the test.[/background][/font][/color]
[background=rgb(252, 252, 252)][font="helvetica, arial, sans-serif"][color="#282828"]I´ll keep testing and keep you briefed, but unfortunately no more comparison will be made because I ´m keeping the CHN. [/color][/font][/background][color=#282828][font=helvetica, arial, sans-serif][background=rgb(252, 252, 252)]Maybe if someone else has the TT gauge installed at the radiator intake can post their numbers, and we can make sort of statistic or reference values[/background][/font][/color]
[color=#282828][font=helvetica, arial, sans-serif][background=rgb(252, 252, 252)]Best Regards from Argentina[/background][/font][/color]
[color=#282828][font=helvetica, arial, sans-serif][background=rgb(252, 252, 252)]. JM[/background][/font][/color]
Posted February 25, 2013 - 03:32 AM
Have you installed any radiator guards? This is the primary complaint with the larger radiators, in that most of the time it's nearly impossible to fit radiator guards to them.
Nope, tried Work Connections but it won´t fit, but it seems they can be adapted. I´ll work on it this month.
Posted February 25, 2013 - 04:03 AM
The china rads fit without major issues on my WR250s though so go figure... also got aftermarket radiator guard to go in without major issues.
Posted February 26, 2013 - 07:23 AM