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Lower engine temp with soft lowers

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Old Apr 3, 2012 | 12:18 AM
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Default Lower engine temp with soft lowers

After reading a post by MKguitar that his bike runs cooler with his factory lowers on I decided to do a test with my after market soft lowers "desert dawgs". I have a 2007 Roadking. Fact: On an 85 degree day in california I made four runs over the same route in the same temp. Letting the bike cool for ten minutes and then completing the route, which was about 45 minutes long. Twice with the soft lowers on Twice with them off. Average head temps for the two runs without the lowers were fron 311 front and 345 rear. With the lowers on 275 front 330 rear. Temps measured at the same spot between the head bolt and the spark plug. I know that there will be a lot of people chime in and say it takes 50 tests and maybe my method was not scientific enough. I will add to the post as I do more tests. I have an oil-temp gauge and the oil temp only dropped very, little barely noticable. If you look at the bike with the soft lowers on though they for a funnel towards the heads makes sense. Only draw back your feet get a little warm but you can always put them on the higway pegs.
 
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Old Apr 3, 2012 | 02:04 AM
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From: Phoenix '53, '88, '09 Big Twins
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the only soft lowers I have seen are the HD which are not very "aero-dynamic" I wouldn't above 50şF.

Interesting, but keep an eye on things.

I based my measurements on oil temp alone ( no oil cooler at that time)
 

Last edited by mkguitar; Apr 3, 2012 at 02:15 AM.
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Old Apr 3, 2012 | 02:04 AM
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From: Phoenix '53, '88, '09 Big Twins
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jeez, website acting up...

cont'd;

I use oil temp as I hope it best indicates an average of motor temps, the hottest areas being the pistons, cylinder bore and heads. Oil carries heat from these areas to be dispersed.

testing was on my 1995 FLHTC 80" evo, stage 1.
( which typically has lower operating temps, BUT less oil volume/pressure and does not have piston skirt oil cooling jets. The evo has generally the same shape motor, with similar fender, forks, fairing and other aero-dynamic features as on current models)

2 X 22 mile loops at 55 MPH ( I live by a freeway) at ambient temp of 105ş, low humidity- test conducted within the same hour.

1 with hard lowers ( unvented) on, one with hard lowers off.

Oil temp was 25ş cooler with hard fairing lowers on.

"test instrument" was the HD thermometer dipstick, which was tested for calibration against my wife's expensive candy thermometer ( Don't tell her ! ). The HD tested accurate all the way up over 300ş

Mike
 

Last edited by mkguitar; Apr 3, 2012 at 02:24 AM.
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Old Apr 3, 2012 | 02:46 PM
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From: Port Orange, FL
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Originally Posted by oldtech
After reading a post by MKguitar that his bike runs cooler with his factory lowers on I decided to do a test with my after market soft lowers "desert dawgs". I have a 2007 Roadking. Fact: On an 85 degree day in california I made four runs over the same route in the same temp. Letting the bike cool for ten minutes and then completing the route, which was about 45 minutes long. Twice with the soft lowers on Twice with them off. Average head temps for the two runs without the lowers were fron 311 front and 345 rear. With the lowers on 275 front 330 rear. Temps measured at the same spot between the head bolt and the spark plug. I know that there will be a lot of people chime in and say it takes 50 tests and maybe my method was not scientific enough. I will add to the post as I do more tests. I have an oil-temp gauge and the oil temp only dropped very, little barely noticable. If you look at the bike with the soft lowers on though they for a funnel towards the heads makes sense. Only draw back your feet get a little warm but you can always put them on the higway pegs.
Just ordered 2 sets of Desert Dawgs today for our Softail Deluxes. I talked to the rep up there in St Francis, MN. They were designed to funnel air into the jugs. We are in Florida and she said she had many Florida customers that keep them on all year round...and she told me that even before I mentioned that we were from Florida. I got what they called "Fog Dawgs". They are the standard desert dawgs only with an extra cut out up top to accommodate fog lamps. I custom made my own wind deflectors that sit atop my engine guard bars right where fog lamps would be. Free shipping with orders over two hundred clams. They should get here by next Wed, just in time for our annual April jaunt from Daytona to Macon GA.
 
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