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Sep 27, 2011 | 09:20 AM

fmnspooch

Thread Starter

Road Master

Joined: Sep 2011

Posts: 894

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From: NJ

Primary temperature

Sorry for all the damn questions lately.

I took a ride out on the highway last night. Maybe 20 miles round trip. Got home around 7 pm and parked her in the garage. I figured I would let her cool down before I cleaned her off. I went back out to the garage around 9pm and starting cleaning off the dust n bugs. I wiped off the Primary cover and noticed that it was still very hot.

Is this normal? I even checked it again at 11 pm and it was still warm...

Just making sure I dont have a problem. How hot is too hot. I just had the whole bike serviced at the local Harley dealership and all the fluids changed.

Thanks!

Sep 27, 2011 | 10:45 AM

fdb2007

Road Master

Joined: Feb 2010

Posts: 884

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From: n

you're overthinking it...it is a big chunk of metal that got very warm and is going to stay warm for a long time. It really doesn't take much more than minutes on the road to get things heated up. I don't even think about cleaning anything on the motor after riding that day. Have a beer and focus on the bugs on the front end.

Sep 27, 2011 | 04:51 PM

Bikenator

Club Member

Joined: Jul 2007

Posts: 463

Likes: 1

From: in a trailer next to a ditch in South Florida

Quote:

Originally Posted by fmnspooch

I use a cheap 14 inch electric fan to blow air over the cylinders from the side of the bike when I park it at home. When parked outside, natural air currents help cool it down pretty quickly.
But, there is almost no air circulation where I keep it at home. I do this to prevent heat-soaking the engine and electrical parts. I usually shut the fan off when the oil temp goes down to 100 degrees on the H-D oil tank temp gauge.

Last edited by Bikenator; Sep 27, 2011 at 04:54 PM.

Sep 27, 2011 | 07:02 PM

Blk and Chrome

Elite HDF Member

Joined: Jun 2008

Posts: 4,109

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From: Connecticut

Yes they get hot and depends on the outside temp is how long it takes to cool, normal

Sep 27, 2011 | 07:19 PM

PanHeadRich

Outstanding HDF Member

Joined: Nov 2010

Posts: 2,591

Likes: 68

From: Big Bear City, CA

Quote:

Originally Posted by Bikenator

You can of course continue to do whatever you like, but a slow cool down is actually more favorable. Aircraft engines are air-cooled as well and very similar in design to our H-D engines. If we're at altitude in an aircraft and just chop power to do a decent, it will crack the cylinders. The term for this is called "shock cooling". It's unlikely that you would crack a cylinder because the temp changes aren't as quick or dramatic as in an aircraft, but it's not of any benefit either. In reality it's more harm than good, and a complete waste of your time and efforts.

Just thought I'd mention that

Sep 28, 2011 | 10:20 AM

carlo

Outstanding HDF Member

Joined: Oct 2007

Posts: 3,178

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From: 50 Miles North N.Y.C.

You guys worry to much.

Sep 28, 2011 | 04:37 PM

Bikenator

Club Member

Joined: Jul 2007

Posts: 463

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From: in a trailer next to a ditch in South Florida

Quote:

Originally Posted by PanHeadRich

Certainly have heard that urban legend of shock coolong a reciprocating engine. Never ever had any form of proof that an engine failure had that as a root cause. I've been a pilot for a long time, though no longer active. Was also a Navy schooled recip mechanic back in the day too. Chopping power on our recip powered helicopters for practice autorotation and recovery back to almost full-power was not only routine training, it was practiced regularly and often. It's still done on a regular basis today, i.e. the popular Robinson recip powered light helicopters do it all the time during pilot training. If what you wrote were even a little true, these things would be crashing regularly due to engine failures, but they're not! Engines are a massive lump of a heat source. The thermal inertia of these units would need to be overcome in an extremely rapid fashion, far beyond anything we can re-produce except in special thermal cycling chambers, to approach anything like a shock effect.

I live in South Florida, the ambient temps here won't remotely allow anything like the effect of which you wrote.
Heat soaking an ECM, BCM or voltage regulator ages these electronic components prematurely There is documented proof of premature aging in abundance, unlike the myth you are repeating.

Last edited by Bikenator; Sep 28, 2011 at 08:23 PM.

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Sep 29, 2011 | 03:10 PM

Bikenator

Club Member

Joined: Jul 2007

Posts: 463

Likes: 1

From: in a trailer next to a ditch in South Florida

Quote:

Originally Posted by oct1949

CHILL OUT before U have a Stroke..

.
Ur for sure worrying too much.

If its 90 out, It'll take longer than if it is 50 for her to cool.

Think bout this.
Go take a ride in U car, then later see if the motor is still hot.

Thanks for the advice on the stroke, just can't let nonsense stand unanswered.
The car electronic modules are well separated from the heads on the (usually) water cooled engine, not so with the Harley air-cooled heads at 350 degrees eh?