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How to Keep Your Motorcycle from Overheating

Posted on 21 Jul 2014 in Harley-Davidson, Motorcycle | 57 comments

Previously, we wrote about how to keep yourself cool on your motorcycle, but if your bike overheats on those hot days you won’t even be able to ride.  One of the first things that you notice when your bike overheats is the loss of power.  What happens after that can be much worse, like a nice hole in your piston.  When the temp nears triple digits, there are few things worse than being stranded on the highway.  Proper motorcycle maintenance and a few add-ons can help ensure that you keep your knees in the breeze and the bike running cool.

Hot weather riding

Cooling System

Let’s start with the obvious.  If you have a liquid cooled bike, your cooling system needs to be up to snuff.  When you know that you are going to be riding in high temps, make sure that you check your coolant levels and that the are where they need to be.  Also check to see that the radiator cap is on correctly.

Then, after the obvious, there are some of the things that you might not even consider.  For one, you might not even think that your coolant can break down over time.  When it does, it can create a mucky mess that will eventually corrode and plug up the cooling system, causing your engine to overheat.  Most motorcycle manufacturers recommend that the coolant be changed every two years to prevent this from happening.

Engine Oil

You might think of your engine oil as a key factor in engine cooling.  Your oil, though, plays a huge part in keeping the temps down.  By properly lubricating the engine, it reduces the amount of friction, which in turn creates heat.  The oil also helps to dissipate the heat throughout the engine and eventually to the outer walls.  Low oil can be a huge factor in engine overheating.  Conversely, too much oil can create too much pressure causing your engine to work harder than it needs to.  Make sure the oil level is right where it should be for the best results.

The type of oil that you use is important for hot weather riding too.  When riding in the hot weather, it’s usually a good idea to choose an oil with a higher weight.  A lower weight oil will become too thin at these high temps to properly lube the engine.  Synthetic oil is an even safer choice because they can endure much hotter temps without breaking down.

For air-cooled engines, it’s that much more important to pay close attention to your oil.  Since your engine only has the air to remove the heat, you need to have the right oil in it to limit the amount of heat that is produced in the first place.

Adding an oil cooler kit will help ensure that that your oil temps stay in a safe operating range and it is perfect for air-cooled V-Twins.  Oil cooler kits like the one from Jagg, route the hot oil from your engine through the oil filter to a heat exchanger where the oil is cooled and then back into the engine.  Some units have fans to cool the oil even faster.  You do need to be careful, though.  If your bike doesn’t need an oil cooler, you should not add one because it will make it harder for the oil to reach the optimal operating temp. If you are constantly riding your bike with extra load on it, like with a heavier passenger or with a trailer behind the bike, an oil cooler kit may be right for you.

Oil Cooler

An easier way to cool your oil, but to a lesser extent than an oil cooler kit, is by swapping your disposable oil filter out for a Speeds Performance Plus re-usable oil filter.  Among its host of other benefits, the SPP oil filter has cooling fins on it that work on the same level as an oil cooler to drop the oil temp.

Re-usable oil filter

Clutch or Drivetrain Problems

You may see increased engine heat if your clutch slips or if your drivetrain causes you engine to work harder.  These issues put extra load on your engine, making it work harder than what it was designed for.  You may not see the effects on the engine when you are riding in cooler temps, but they will rear their ugly heads once they are compounded with the excessive heat from the weather.  Make sure you resolve these issues before you take a ride on a really hot day.

Brake Hanging Up

Not only will your brakes get overheated when they hang up, but your engine will as well.  Just like the clutch slipping and drivetrain problems, your engine can be put under too much load when a brake is dragging.  Make sure that your brakes are adjusted properly before a ride on a hot day to eliminate the unnecessary excess heat.

Cylinder Head Cooler

If your engine is still overheating, you may want to consider a cylinder head cooler.  The Cylinder head cooler works by having a fan force heat away from the engine by pushing high velocity air through the cylinder fins in a wide flow pattern.  The JIMS ForceFlow Cylinder Head Cooler can automatically turn on when the temps rise too high.  The ForceFlow can lower the head temps on your Harley by up to 100 degrees.

Cylinder Head Cooler

With these things in mind, you won’t have to worry about overheating your bike and getting stranded in the middle of the desert.  Just make sure you keep your body cool too.

Check Out All Motorcycle Cooling Systems


Ryan is one of the lucky ones who gets to combine their passion with work. He has enjoyed powersports his whole life and now gets to write about it. Ryan has been around the industry since High School and continues to enjoy learning and sharing about powersports with others in his role at DK.


  1. deric / July 26th, 2014 23:27

    But u are not suppose to use synthetic oils on any motorcycle because the clutch will slip

    • Ryan / July 28th, 2014 8:16

      Hi Deric. It is true that if you use an improper synthetic oil for your bike that you may experience clutch slip, but it can work just fine when using the proper synthetic oil made for your motorcycle. Try to avoid automotive synthetics because they contain extra additives that can be hard on your bike.

      • richard mccannell / June 14th, 2015 0:06

        All oil provides a rating which indicates the viscosity. The lower the rating, the lighter the oil is, meaning that it flows very easily. This is not an issue at low temperatures, but as the engine heats up, it will rapidly begin to degrade, and get very hot. As a result, drivers want one with high viscosity to ensure smooth running of the engine at high temperatures. Many come with a combined rating such as 20W-50, indicating that at low temperatures the oil flows smoothly and as the engine heats, it retains its viscosity. Single grade is available, but multigrade is recommended.

        The claim made by many manufacturers of specially formulated motorcycle oil is that which is designed for cars may actually damage the engine of a motorcycle. This is simply not true. While some designed for automotive use is not optimal in motorcycles, most oil is easily interchangeable, although motorcycles are more demanding than cars are. Motorcycles still operate along the same internal combustion principles as cars do, after all.

        In scientific testing, it has been determined that motorcycles will break down oil more quickly than cars, with the results being the same for both types. Oil breaks down as repeated circulation shortens the polymers in it, causing the viscosity to be lowered. In addition, increased oxidation and repeatedly running too hot will cause it to break down and become less effective. Testing also determined that synthetic oils are not as subject to break down as natural ones, and are therefore a better choice for drivers.

      • David / June 14th, 2015 19:56

        you can use Amsoil in all three holes

      • sree / February 10th, 2017 21:24

        Sir,i am using pulsar150 classic..old2003 model.. Sir i am facing the problem of over bike is getting heated at 1to2km..and mileage shortage…can u plz hlp me.tell me some ways to solve the problem

  2. Javier C. / September 8th, 2014 18:48

    Good list of “to do” solutions. Particularly like the idea of a reusable SSP oil filter. My Triumph Bonneville would undoubtedly benefit from such an item. Will also talk to my dealership about my new Triumph Speed Triple’s possible enhancement by using the SSP filter. Thanks.

  3. Denny R. / September 9th, 2014 15:18

    Yep, Agree with Ryan 100%, but I would expand on that to say try to avoid ANY automotive oils mineral or synthetic. Use only motorcycle formulated oils synthetic or mineral. And yes the good synthetics will run cooler with excellent cold flow property’s as well, it is the only oil I use.

  4. gerrie / January 20th, 2015 7:53

    Is it possible for a bike to overheat at high speed when you had a sprocket conversion

    • Ryan / January 20th, 2015 10:51

      Hey Gerrie, it is possible that a sprocket conversion could cause this if it is making the engine over-rev. If the sprocket conversion created lower gearing, the engine could be working too hard at higher speeds and begin to overheat. A small change shouldn’t cause this to happen though, unless in extreme conditions.

  5. Henry G. / March 16th, 2015 22:51

    I’ve used synthetic oil made for motorcycles on my 02 suzuki TL 1000R although since the previous owner changed the original gages I’m blind to the temp ? I’ve run a rocker switch u can manually turn on the dual fans with and my mind is set on running some type of aftermarket gage ,what do I do run the wires from the existing temp sensor ? Help!I don’t want to over heat for summer,Thanx.

  6. laurie cotenas / June 13th, 2015 23:03

    Do they have these ssp for a sportsters?

    • Ryan / June 15th, 2015 8:07

      Hi Laurie, the SSP oil filter will work Sportsters.

  7. Fred Wudell / June 14th, 2015 0:19

    I have a vrod and use the Amsoil 20/50 and have used the reusable oil filter on my Honda XR600 for many years with no problem so I put one on my vrod as well

  8. Steve Herrington / June 14th, 2015 8:15

    Full-synthetic oils, even motorcycle formulations, are not recommended for All bikes. Victory specifically recommends semi-synthetic as the composition of their clutch plates does not like full-synthetic and they will slip. I also do not agree with using a heavier weight oil, the oil passages in the engine are designed for a specific weight.

  9. David / June 14th, 2015 19:58

    I did see anything about LoveJugs cooling fans, ohh this is Dennis Kirk I forgot

  10. Kou / June 30th, 2015 22:29

    Hey Ryan

    I just got my first bike and I stalled that thing way too many times to count. Was stuck out in 95 degree heat for three hours and to top it all off, I was cruising up and down steep hills the entire time. I think my motorcycle might of overheated because the bike won’t start and the oil chamber, in particular, is feeling hot as hell compared to the rest of the bike. Am I right thinking that the intense heat of the oil is the reason why my bikes not starting?


    • Ryan / July 1st, 2015 8:16

      Hey Kou, there could be a few reasons as to why your bike won’t start and you will have to do some troubleshooting. I would start by making sure that you still have good spark. If you do, check your compression to make sure you didn’t blow a head gasket or broke a ring. If you still need some help, contact our techs and they will be able to walk you through a few more scenarios. 320-358-3409 or by email at

  11. Rick / July 17th, 2015 19:01

    Is it possible for the clutch to stop working if oil cooler is plug with mud? 2910 cvo ultra classic

    • Ryan / July 20th, 2015 8:33

      Hi Rick, which part of the oil cooler is plugged with mud? If mud got on the inside, then yes that would be bad for everything. If it was just the outside that got plugged, the only thing I could see is if the excessive heat somehow boiled the fluid in the clutch lines. To help you troubleshoot this further feel free to contact our tech team at 320-358-3409 or by email at

  12. Chris / August 7th, 2015 8:18

    There is a new bad boy in production from Stars design called the BFF1000. A cooling fan that’s a tab bigger in air volume than the Harley parade fan. More technical looking and actually I think it looks like it should be there. Simple install and the testing they did is real. I hop the border all the time and endure a line up for more than an hour and can run constantly no problem.

  13. Butch / August 10th, 2015 16:33

    I have a 06 Fatboy that runs hot after a 35 mile ride. runs fine and when I stopped for a red light it went dead. I have noticed at times it backfires and tyres to go dead at idle.I Have to rev it to make sure it don’t stop. what do you think I should have checked?

  14. Butch / August 15th, 2015 21:25

    have a 06 Fatboy that runs hot after a 35 mile ride. runs fine and when I stopped for a red light it went dead. I have noticed at times it backfires and tyres to go dead at idle.I Have to rev it to make sure it don’t stop. what do you think I should have checked?


    • Ryan / August 17th, 2015 8:35

      Hi Butch, I would start by cleaning the IAC (Idle Air Control) valve. These can get plugged up and cause your engine to not idle properly.

      • Butch / August 31st, 2015 21:36

        where is it and how do i clean it? Thanks for your help.

        • Ryan / September 1st, 2015 8:20

          To get to the IAC, you will need to remove your air cleaner assembly. The sensor hole for the IAC will be located at the top of throttle body. Use some mass airflow sensor cleaner to spray out the hole. You can get the spray at any auto parts store. Hope this helps.

          • Butch / September 1st, 2015 11:50

            Thank will do

  15. MAZI / October 9th, 2015 18:10


  16. william alfeche / October 26th, 2015 4:00

    hai,,, what shoud i do for my motorcycle,?when i travel a long distance i noticed every time im got stop for refuel,, its hard to restart my motorcycle,,,, other says that my motorcycle get overheat,, and i have to change the valve,,,,, other say that i have the cdi also,,,, hope you can help me,,, could you please send my email your answer

  17. william alfeche / November 6th, 2015 6:40

    what kind of oil that are suitable for 125cc common motorcycle?

  18. muhammad shahzad rana / December 31st, 2015 7:35

    my bike is cd70 cc is old version, plz tell me what is the reason my bike ride just 3.5 kilo meter and its head is burn, mechanics says its head value problem, plz tell me sir what do u think, that this is really value problem.

    • Ryan / January 4th, 2016 8:22

      Hi Muhammad, without having the bike in front of me it’s hard to tell. It could be a valve problem. It could have been running on a lean fuel mix too. If you want, you can email our tech team at and they will be able to help troubleshoot your issue further.

  19. SAK / January 31st, 2016 19:25

    I just bought a new apsonic China motorbike which i intend to use for work so please advice me on the type oil i should use and how many kilometres i should cover before i get my oil changed.i it’s air cooler and we have a very hot weather here as well.

  20. md sajib / February 12th, 2016 10:37

    Dear sir
    My bike is hero splendor 2004
    My problem is 3 to 4 km ride this bike than gearbox is very hot (unreachable).
    I will Chang connecting rod,all bearings,piston,
    Problem not solved. Bike start kick by kick , no problem.
    Now what can I do please tall me what?

    • md sajib / February 13th, 2016 10:59

      Not unreachable is it Untouchable

  21. Punit Kalyankar / February 24th, 2016 0:50

    How to fit oil cooler to 125 cc bike

  22. adama timileyin / March 20th, 2016 14:25

    My bike do off when heat even not going to far distance

  23. subrata choudhury / March 21st, 2016 11:27

    I have 150 cc honda make unicorn dazzler. Recently I have changed both the crank case cover of the engine. Now engine oil is easily overheated and unable to deliver power. Prior to crank case cover change there were no engine overheating. Company workmanship was excellent.
    Please give me possible solutions.

  24. Nate Ross / June 25th, 2016 14:16

    Got a 2003 kawasaki ninja ZX-6R (636B) keeps overheating on me, I put a new radiator in at the beginning of the year (old one had a hole in it, that’s what I figured the problem was) bike ran good for a few rides then continued to over heat, checked oil level it was a little low through some oil in it, still overheated. Took the thermostat out checked it, works fine, threw it in the freezer got it real cold then threw it in a pot of boiling water the sting shrunk down allowing space for fluid to come though. My next thought is either the radiator cap, or the head gasket. I’m about to do a complete tune up on the bike and see where that gets me. Any suggestions or thoughts?

    • Ryan / June 27th, 2016 8:26

      Hey Nate. When you replaced the radiator, did you bleed the cooling system when you added more fluids? Sometimes air bubbles can get trapped in the system and cause overheating.

  25. Jeff / July 31st, 2016 12:48

    I have a 2011 roadglide, after about riding around town for about a hour. My clutch won’t engage. It’s get real easy to pull in and I’m not able to shift gears. It actually stalled out at a red light. After sitting for about a half hour, clutch is working normal again

  26. Tom Tailor / August 16th, 2016 1:25

    Extremely useful article! will certainly keep in mind.

  27. Shadak Ali / September 16th, 2016 13:53

    How I will understand that clutch is slipping

  28. Vignesh Dhandapani / October 13th, 2016 5:42

    I need some suggestion, I own a KTM RC 390 with 9000 kms on it. Quite recently i am facing a lot of over heating issue. I also replaced my radiator set which had a leak. How do i prevent it from over heating? Right now i am using a motul inugel coolant a KTM service station specified. Please advice.


    • Ryan / October 13th, 2016 8:08

      Hi Vignesh, Our Tech Team should be able to help you troubleshoot your overheating issue. You can contact them by email at

  29. Roscoe / November 7th, 2016 18:11

    I have a 012 kawasaki vaquero they all seem to run very warm what do i do to cool it down

  30. Mayank / December 27th, 2016 0:43

    I want to own a harley davidson fatboy but i am getting lot of negative reviews. Many have suggested me to go for triumph thunderbird storm instead as it is a liquid cooled engine and thus cause less overheating. What would you suggest ?

  31. sanjay / March 17th, 2017 12:14

    Hi, Sir
    I need some suggestion, I own a Hero super splendor 125cc bike i want to know that how maney kilometer i can ride my bike without any stop ? Thank you .

  32. Jonah Levine / April 16th, 2017 21:07

    Hi Ryan, I’m going to be riding a 1980 Honda CM400T across the country this summer, and will be going through the southwest which I’m sure will be over 100 degrees most days. It’s air cooled. Do you think this will be okay? Which option do you suggest I do to help it to not overheat? Thanks!

  33. Marz / June 18th, 2017 8:52

    Hi quick question I am riding my 04 Yamaha R6 am I live in southern Utah where we have temps at 115 how can I do they make anything to help cool this engine I am using engine Ice right now but on a short ride last night my bike started over heating

  34. Richard Bekoe / February 23rd, 2018 4:47

    Am using Honda cb750 when i run it about half an hour none stop it get overheated when i off the engine it will not start though the starter will run the engine alright but not start it will take two hours when the temperature normalized just a touch to the starter button it start .Am emailing you from Ghana in West African , sorry its oil coolant engine not water , may i also know if oil cooling engine has Thermostat in the engine thanks in advance look forward to hear from you.
    my best regards
    Richard Bekoe

    • Ryan / February 23rd, 2018 8:08

      Hey Richard, this sounds like an electrical issue. You can email our Tech Team and they will be able help you troubleshoot this step by step.

  35. Alan / March 2nd, 2018 6:33

    Hi Ryan, I just bought a Honda Magna 250 v-twin and I’m a noob to bikes. When riding it home after about 15 min I had lack of engine power then it cut out. I tried to start it abut it wouldn’t fire up, so I decided to wait for 5 min before trying again and it worked. 5 more min down the road the same thing happened. This time I listened to the bike with the ignition in on postition and couldn’t hear the radiator. I then waited 10 min then fired her up and got home safely. The next day I fired her up and she started first time but I didn’t ride her. Anyway do you think my problem is the radiator? I took a look at the radiator and I think it’s seen a lot better days.

  36. Steve morgan / March 5th, 2018 10:28

    2009 road king, air cooled. Will be riding in Arizona during summer months. Will my bike overheat?
    What do I need to add to prevent overheating.

  37. Melissa / April 21st, 2018 20:31

    Hi I just brought a Honda 2017 bike and only rode it twice and now it is overheating and make a clicking notice but once it is cooloing down the noise eventually goes. Why is this happening when it’s a new bike.

  38. Joe D / April 27th, 2018 13:11

    I just changed the engine oil on my 2011 fatboy a week ago, I was idling my bike for 30 min ion 55 degree weather got on the bike she started pinging figured it was over heating rode ez around the block a few times pinging slowed down ,am I in for trouble down the road? Thanks Joe

  39. Justin / January 29th, 2019 12:43

    I highly recommend that folks read Terry Dyson’s blog about motor oils, as he has extensively tested a number of motor oils in extreme conditions to see what their wear properties are. He has busted a couple common myths regarding oil. One of the main ones is that synthetic is always better as to lubricity, temperature stability, and otherwise all around. Some conventional and semi-synthetic oils scored quite well, and above many other synthetic formulations.

    And might be surprising to some, but a plant based oil scored extremely well. In fact, out of straight from the bottle only tests (he also did some combos with add on oil additives/conditioners), one of the plant based formulations scored 3rd place as far as psi wear protection, and furthermore lost only .7% under extreme heat testing of 275 F, though it’s break down point was also at that temp (some oils tested were a little higher and some a little lower as far as thermal breakdown point). This is surprising because that oil tested was a 5w-30w weight, and one of the common beliefs/perceptions is that lighter, higher viscosity oil doesn’t do as well as thicker, more viscous oils at higher temps and pressures.

    In fact, the straight out of the bottle oils that tested the best out of all of them, were 0w-20w synthetic and 5w-30w Amsoil products (part of the Signature series). They provided not only the most protection from wear, but also had a fairly high temp protection level (lost 7% at 275*F), as well as high temp stability (thermal breakdown at 295, which was higher than many others). Yes, these were full synthetics, which seem to support the first mentioned belief, but again, a plant based oil was in 3rd, not far behind, and then there were conventional and semi-synthetics also in the “fantastic” range.

    I realize that some of these oils are not appropriate for many motorcycles because of clutch issues, but the point is that the general extrapolation can apply to other oils and other combustion engines. I have a Ninja that is currently down, but I also have a Fly 150 scooter that is running, and I plan to try the plant based oil that ranked 3rd in straight from the bottle. Was able to find a quart of same for a little over 6 dollars, which isn’t too bad and considering it’s more biodegradable (in the open environment) and renewable, and has outstanding wear protection across wide temp ranges, seems more than worth it. It’s too bad I can’t also use it for the Ninja!

    The article can be found at:

    It’s very long, to get to the actual ranking, go down about 1/7th of the page or so.

  40. Isaac / January 22nd, 2020 9:16

    Honda Forza 250 Problem. When I travel about 25 kilometres the engine stops as if there is a fuel shortage. After 20 minutes when you start the engines it starts but is not able to take you more than 10 kilometres.


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