Fan cooling GS500f

[electromage]

I've read in a few threads here  that it's bad to shut down the engine when it's hot, or let it idle, such as sitting in traffic. I'm wondering if it would be beneficial at all to mount a fan to the front of the engine/radiator. I have some large 12V brushless fans from servers that will push/pull quite a lot of air, and I can build a small thermal controller to keep it spinning at the right speed. Does anyone see any reason why this wouldn't work, or why it would cause other problems? (The fans are 12CM square, and pull 1A at 15V.)

[ohgood]

you could put fans on it, but all the other bikes do just fine without a fan...

just keep an eye on your oil level and enjoy the ride

[Roadstergal]

If it ain't broke, fix it until it is.

[qwertydude]

Only on rare instances did I ever notice my bike get too hot, shifting would get notchy until it got cooled off again on a long straightaway. Other than that I'd say it's fine. That particular instance was Las Vegas 115 degree weather in almost parking lot stop and go traffic for half an hour, can't split there so had to sit in traffic. So unless you're facing even tougher conditions than that you really don't need a fan. Oh and it always comes up that you're in the muggy south or whatever. Engines don't see muggyness and humidity, so 90 degrees at 100% humidity might suck for you but to an engine it's just 90 degrees which isn't bad at all compared to a sweltering 115 desert heat, again doesn't matter that it was a dry heat, it's still heat.

[fred]

You'll just kill your battery. The GS will be fine, don't worry about it. When it does get super hot out, just check the oil more frequently... I rode in LA all last summer with no problems at all, even on days well over 100...

[ecpreston]

and I can build a small thermal controller to keep it spinning at the right speed.

what temperature would you measure and how? 

I was worried about it too. Not having a temperature gauge of some sort drove me nuts. Now that I've done a track weekend in 100 deg heat, burned very little oil, and it didn't miss a beat all weekend, I've learned to trust the design of this engine.

[sledge]

A great solution.............. to a problem that doesnt exsist.

[jp]

Unless you regularly get stuck moving at walking speeds or less for extended periods, this is really a non-issue. If you do find yourself in these types of situations, get an oil cooler if your bike doesn't already have one. Somewhere around 280-300°F is where you'll start to break down regular oil if it stays that hot. A small fan to help move air through an oil cooler might help with this, but if you're moving slowly enough to create those temps, you aren't putting out enough voltage from the charging system to power the fan without draining the battery.

[vorBH]

Drain the battery? It's a little fan!? lol....how can it dramatically drain the battery?
I was thinking to put on a fan to hit the oil cooler as well....if I do it it will be later on, but I am not so sure now....

[jp]

The drain may not be great, and in fact probably isn't, but if you're stuck in the kind of traffic which is likely to cause the oil temp to rise, you are probably running the engine at low enough RPM to not be fully recharging the battery anyway.  If the charging system is not operating correctly, it only shortens the time till you are sitting on the side of the road waiting for help. Probably not a major issue, but one that should at least be considered before adding anything to the electrical system.

[fred]

Drain the battery? It's a little fan!? lol....how can it dramatically drain the battery?
I was thinking to put on a fan to hit the oil cooler as well....if I do it it will be later on, but I am not so sure now....

From a quick google search, most motorcycle radiator fans seem to be 60 to 80 watts, some as high as 100. The stock headlight has a 55/60 watt bulb. Running a fan would be like having an extra headlight running at minimum, probably more. The GS charging system doesn't have a lot of headroom and doesn't even charge anything below 3000 rpm so if you're sitting at idle running the fan and the highbeams are on, you're likely draining the battery.

[vorBH]

Yea but....really....it probably takes like 1hr at minimum to fully drain the battery...no? even with that situation described above with highbeam and an 'extra light'

[fred]

Yea but....really....it probably takes like 1hr at minimum to fully drain the battery...no? even with that situation described above with highbeam and an 'extra light'

I think you're overestimating the capacity of the GS battery. A week of going on short rides while running the fan would probably be enough to get you in trouble with anything but the newest of batteries. Why do all the work of adding a fan to a bike that doesn't need it and risk killing your battery and getting stranded? Also, I challenge you to find a post on this board about someone overheating who didn't have a crazy lean mixture. If your bike is running correctly, you shouldn't have trouble with it.

[vorBH]

True true....but if my engine overheats and seizes...you owe me a new gs500 engine..deal? lol 

[Grommett2k]

A great solution.............. to a problem that doesnt exsist.

Exactly

[jp]

A fully charged battery will read about 13.1 volts with the bike off. Somewhere between 11 - 11.5 volts is where the bike won't run. That isn't really that wide of a range given the relatively small reserve that motorcycle batteries have. If I regularly rode in an area where a fan assist on the oil cooler would be a worthwhile addition, I would probably find a way to turn off the headlight to reduce the power draw when the fan was on.

This isn't a problem that doesn't exist, it's a problem that few riders will encounter, and most of them will only do so a few times. My 82 GS1100E has an oil temperature gauge. A group of friends and I were returning from a trip to Niagara Falls, and got stuck in a backup at the border. It took about 20-30 minutes for the oil temp to get to over 300°, when the normal was about 240°. Another time I was stuck on a toll road in the Chicago area waiting to get through the toll gate in rush hour on a 1980 GS750. I'm not sure what the temperature got to, but form the way my legs were roasting, and from the condition of the oil when I changed it the next week, I'm sure it was over 300°. Anyone commuting in an urban area with toll roads/bridges could find themselves needing a boost to the cooling system on a semi regular basis, depending on their travel time and routes.

[vorBH]

There we go makes sense, problem DOES exist......its an engine, it will overheat like any engine out there....But I never realized the problem of draining the battery (and I still think it won't be much, but thats because I am thinking like a computer fan hitting the oil cooler....connected to an on/off switch)

[sledge]

Anyone else know how to use and apply Ohms law??  Power = Voltage x Current

The figures are 2A total at 12v......that means the fans will draw 24w from the system, thats less than one half the power of the headlamp bulb.....and slightly more than 1 indicator bulb.

If you left it ticking over you would probably run out of gas way before the battery died 

[fred]

There we go makes sense, problem DOES exist......its an engine, it will overheat like any engine out there....But I never realized the problem of draining the battery (and I still think it won't be much, but thats because I am thinking like a computer fan hitting the oil cooler....connected to an on/off switch)

Wait, dude, you live in Toronto? According to this wikipedia article:

http://en.wikipedia.org/wiki/Geography_and_climate_of_Toronto

The highest temperature ever recorded was 106 F and that was in 1936 during a heat wave so bad it was given a name! You would have to go on one heck of a road trip before you even got close to an area capable of being hot enough to seize your engine, and once you got there, you'd have to get caught in wicked traffic for a long while. I don't understand how you could possibly be worried about heat. If you feel like doing a modification to allow you to ride more often in extreme weather, put a block heater in the bike so next time it gets near -40 you can still get the GS to start. That would be a mod you'd be way more likely to need given your location...

[electromage]

I did say that the fan pulled 1A at 15V, it also pulls .78A at 12V, which is 9.36W. Probably about the same as the turn signals I was thinking mostly about the fan itself obstructing airflow when the bike is moving.