Author Topic: Cooling fan speeds up with throttle, normal?  (Read 3415 times)

Offline voodooskin

  • Motobrick Curious
  • Posts: 41
  • gone: 1997 K1100LT
Cooling fan speeds up with throttle, normal?
« on: April 01, 2016, 01:41:28 AM »
I truly apologize if this is a dumbass question but I am whack when it comes to electrons:

I have one of those spal aftermarket cooling fans for the radiator described elsewhere on motobrick, the OEM fan needing replacement.  Maybe 25K since the fan went in, no real issues.

I put a manual switch in so I could turn the fan on whenever I liked, described elsewhere on motobrick.  Good value so far.

At idle, if the fan is on due to heat or me kicking the switch, you can hear it  cranking away down there.  If you raise the RPMs by 4-500 the fan spools up noticeably faster.  Drop RPMs, fan drops speed.  I think it's always been somewhat like this but now it's quite pronounced.

Is that typical behavior or does that indicate an issue with the fan or alternator or something?  The battery is a fairly new Odyssey 680 and holds a charge great, never needs the trickle charger, probably perfect.

'97 K1100 - no heated gear or anything not stock other than a headlight relay system added (again thanks to motobrick…).  I have a couple of the free Harbor Freight digital multimeters and would be delighted to put one to use if I knew what it does…

Thanks!
  • Oregon
1997 K1100LT 49K miles

Offline Scott_

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Re: Cooling fan speeds up with throttle, normal?
« Reply #1 on: April 01, 2016, 06:57:53 AM »
Connect up a volt meter and watch the voltage to confirm it if you would like, but yes, when the bike system voltage changes so will the speed of the fan.
Just like your lights. When you are at idle and your alternator isn't putting out any charging power your system should be in the area of 12.6-13.0 volts. Run the engine speed up a bit for the alternator to engage and start charging(14.0-14-7 or so) your lights will get brighter.
  • My Garage
1995 K1100LT 0302044
2017 FLHTK Ultra Limited
1997 K1100LT 0302488 (R.I.P.)
1997 R1100RT ZC62149(sold)
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Offline johnny

  • TrailBrakingThrottleWhacker
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Re: Cooling fan speeds up with throttle, normal?
« Reply #2 on: April 01, 2016, 08:42:29 AM »
greetings voodooskin...

i think its reversed polarity... proally cause your battery to explode... which is located directly below your taint...think about it...

j o
  • :johnny i parks my 96 eleven hundert rs motobrick in dodge county cheezconsin  :johnny

Offline voodooskin

  • Motobrick Curious
  • Posts: 41
  • gone: 1997 K1100LT
Re: Cooling fan speeds up with throttle, normal?
« Reply #3 on: April 01, 2016, 01:58:48 PM »
greetings voodooskin...

i think its reversed polarity... proally cause your battery to explode... which is located directly below your taint...think about it...

j o

Russell Day-Long my good man, bet I won't even notice   :neener:
  • Oregon
1997 K1100LT 49K miles

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