Harley Overheating

QuestionHello, hope all is well with you. I have a simple two part question for you. What is the normal operating temperature (engine) on a 2007 road king classic with a 96 cubic inch motor.. and what kind of temperature readings should I expect to get on the head pipe between jug and O2 sensors?

I have a super tuner, big sucker, rush ceramic pipes and rush mufflers with 2.25″ baffles. I get about 324-340 degrees F on jugs right beside the spark plugs, and anything from 560-700 degrees F on the head pipes. Is my Harley overheating? Any info would be great..

Thanks,
Bill

Answer Hi Bill, Standing at idle for how long?

324-340 not bad and if you are driving down the road it would be cooler.

The trouble happens in traffic or any long periods of the bike running and standing still.

Passenger comfort, hot legs, from the rear cylinder and exhaust are usually the issue.

You can install an oil cooler to help the m/c run cooler and a cylinder cooling fan to also help cool when standing still.

QuestionMy last ride was in December, NYC Veterans Day Parade. We left from Staten Island it was 44 degrees, got to city traffic was dead stopped temp was near 70 now. Trying to get to the parade line up took 1 hour doing 5 mph, my bike idle went lower and I had to keep throttling up to keep it from staling. Well it did stale 2x, and was running the same until we got to destination. parked and waited for us to enter and lead the parade. It ran ok, not great. But going home doing 55-60mph it ran perfect. Any answers what would cause this, this wasn’t the first time it happened, seems to be over heating, I use synthetic Amsoil. My bike is a 2006 Road King with 20,000 miles.

Answer You bike was over heating. Parades are torture on an air cooled engine. Not only is there no air blowing across your motor; but your air intake lacks fresh air as it sucks in the exhaust of the bikes in front of you. If you plan on more rides like this, we strongly suggest that you add a fan to your ride.

Check out this assembly from Love Jugs. It’s an excellent kit. Looks great. Works great. Top quality and an AMERICAN company. They were a pleasure for us, at FMH to work with.


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Few videos with more info:

Cool-Master Video
Cool-Master Install
Love Jugs Stop Harley Overheating
JIMS USA ForceFlow Engine Cooling Fan
UltraCool Oil Coolers

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34 Responses to “Harley Overheating”

  1. Chris Reyes

    I just put the turndown pipes on my 2004 Sportster 1200. The engine seems a little hotter than usual. Is that normal?

  2. GUY

    I have a 2006 Road King with 80k miles. I have replaced every sensor and intake seals twice, new fuel injectors, etc. Bike has new camchest (hyd chain tensioner), S&S 2-1, Pwr Cdr V and 203 cams. New plugs, wires and coil. Problem: Engine miss at running temperature, various throttle positions/ load conditions. Seems to worsen as engine gets hotter. No problem at idle (cold or warm), except rough idle when hot (sitting at idle for ~20 min after reaching normal run temp). I think I’m seeing cylinder/ head thermals causing movement that allows air intake seal leaking. I use starter fluid around seals and engine rpm drops. Flanges are torqued and I even lapped flanges to get tighter squeeze. Ensured symmetrical seal/flange-to-head fitment when I changed the seals. Is this an engine overheating issue? Do high temps affect the ECU based on temp sensor readings? Please advise as I’m running out of ideas and my local mechanics are puzzled…

  3. Paul

    I need some suggestions to best lower 3" inches on a 2018 Harley Softail Breakout FXBR. The 3" inches is need to safely plant feet on the ground. I was thinking 1" inch from the chair to include pushing forward of approx 5' inches (this will allow feet to be comfortable on the forward controls as well as arms to control the bar). I'm also thinking of floor boards. Now the other 2" inches from the shocks... i'll need suggestions from you folks that has experience!! I'll appreciate any advise you can provide and can range from altering performance to cost . Thanks Paul

  4. Will Solen

    Bought first bike in 1963 and been riding since. Rode motors (HD) for the largest PD in S Florida for over 9 years most of the time in hot weather. If I've learned nothing else about Harley's I did learn that the slow riding, parades and funeral details, will kill the engine. The tech's were absolutely correct in their answer.

  5. Brian Gibson

    What would be causing add to act like after a long trip at idle to for it to die then file right back up

  6. Bob Haddox

    I altered my pipes now my rear cylinder is running hot do I need to get it remapped or what is the fix for this problem?

  7. Chuck

    I have a 98 Electra Glide with the same problem out of the front cylinder! It gets extremely hot, losses oil pressure and smokes out of the front cylinder! I was even riding down 295 during October thinking it would cool down but when we got to our destination the oil light came on, no oil pressure and the bike stalled out, had to let it sit for a while before it would start again!

  8. Leonard

    <strong> NB Ticket 19350 I have a 2013 Road King Classic with the 103 that I rode in a parade this past weekend. Once the parade started moving, I realized it was a bad situation as we were only moving 1-2 mph. Overheating bikes were everywhere. I decided to ditch the parade route and got on the road to cool my bike off. Once it sat for about 2 hours, I took it home, around a 10 minute trip. I noticed the bike was having issues running at idle; acting like it wanted to stall out. What could the issue be? Appreciate any info you can provide.

  9. Vincent devitt

    </strong> NB 17082 Ticket I have a dynamic street Bob 2008 ! My problem is , that after riding 20 / 30 miles she starts to splutter and cough and so have to stop and switch her off , she will ride ok from cold but once she gets hot same problem ! I have been told that the ECU is kaput finished but some guys tell me that if that were so the bike would not function at all ?? I've tried a crankshaft sensor cable but same problem do think that the ECU is screwed and would a new one slove the problem hoping one of ye can help me out ! Any advice please This

  10. clivemoxy

    2014 Rushmore low engine management light and fan not kicking in,done test and fans work could it be a temp sensor ?