Yeah, the fans should be reversible. They may not flow as much air, and as the radiator is slanted, it would be harder to push air through the radiator backwards but all of that said, it may well work; the C-14 has a very robust cooling system and so if the overall fan efficiency was knocked down by, say, 10% or 15%, and the system has 50% excess built into it, then it would still work fine.
I certainly would not recommend trying to force the air through the radiator backwards once there is any forward motion though. Doing that is going to make the fans directly fight the normal airflow generated by the bike moving and would end up preventing airflow through the radiators, at least at some speeds. And seeing as my fans often come on at low speeds (guess: less than 30 MPH) even on a modestly warm day (80's F), I think defeating the fan flow would not work out.
I also do not think it would be desirable to instantly reverse the current flow and direction of an already running fan because it will probably generate a large current spike. So there should be some time delay between running forward and then running in reverse (and back again) when stopping. That could be done with time delay relays but they are expensive and the system would still need some means of sensing when the bike is not moving. That will be the more difficult part, although a crude but effective 'speed check' electronic device could be made using a timer / counter chip (such as a 555) and having the vehicle speed sensor reset it. So once the bike stops, the timer would time out and engage the electronic 'stopped mode'. But then you would need a method to reverse that too, so the easier way, IMO, would be to use a MCU for all functions in the fist place. That way all parameters would be controlled by code and easily changed during the testing phase (often called Research and Destroy).
All of the automation aside, one could try it with nothing more than a couple of relays and a three- position switch which would be used for Forward (normal), Off and Reverse. You could trigger the switch with your fingers and try out the whole system that way.
And YOU are living in one of the best ambient temperature test- bed areas around Marty.
It does not get that hot here and besides, when it does go into the mid- 80's and above, I hide behind A/C in the car and house like Mary Jane Tinklepants 'cause I hate it when it is hot. But where you are, a 100F day is merely warm, right?
Brian
I'm not sure how complicated the automatic part would be, but the fan reversal (manual) should be a relatively easy mod for those that know their way around relay wiring. Since the ECU only controls the fans relay, it could care less whether the fans are running forward or reverse. As long as there are no unseen diodes inside the fan motor housing I would think a DPDT relay could be inserted between the fan relay and the fans. Control it from a LED switch (red I think) where the LED is lit when it's reversed. Now how complicated would it be for automating it?
I wonder if the fans are powered off automatically by the ECU at a certain speed? Anybody know?...anybody? anybody?...if they are, then having them reversed all the time wouldn't necessarily be a bad thing. (?)
It is certainly something I would look into if I used my bike as a daily commuter.
