Radiator Cap 1.1 VS 1.8 Explained - Dirt Bike Overheating 

Use the coolant the manufacturer recommends. Gylcol based is the most common. 50/50 seems to give the best for heat protection, preventing freeze up in the winter, for preventing corrosive buildup within the radiator and/or coolant passages within the engine. In addition, 50/50 mix of glycol and water works best for providing the water pump with proper lubrication. In a lot of racing organization (such as auto racing and paved track motorcycle racing) glycol based coolant is actually banned. This is because if any gets on the paved racing surface it is very slippery. Do not forget to change the coolant on a regular basis as the additives within it can get used up. If using straight glycol based coolant, mix with distilled water (do not use tap water as there are usually salt and minerals in tap water). Distilled water is easy to get at a lot of places. If your vehicle still has a warranty, use what the manufacturer recommends or you could void your warranty. Never release the pressure cap (whether on the radiator or recovery bottle) when the system is hot. Venting while hot could cause the coolant to explode violently outward and badly burn you. Make sure the radiator hoses are cool to the touch before releasing the cap.

Try engine ice I was overheating my 250F in Glamis which is deep sand but I flushed my system and ran some engine ice and my bike runs ALOT cooler now

Using a high pressure radiator cap on a cooling system designed for much lower pressures will put the radiator hoses, head gasket and radiator at risk of rupturing under higher internal pressures.

There's a few things I'd do first before doing this. 1.service the cooling system with a flush and new liquids. 2.clean and fix the radiator fins. 3. make sure you don't have paint or blockages in the system as internal paints can come loose and clog up the thermometer and smaller passages. 4. check that you don't have an air bubble in the system. Bikes don't just get hot all of a sudden. They are designed with tolerances in mind as to not cook the motor.

I went from an OEM 1.1 to a Tusk 1.8 with a built in guage and blew a head gasket. I'm guessing to much pressure in the system. Ok, new discovery and a rookie mistake. When washing my airbox the plastic cover that's takes place of the air filter was installed wrong. Pushing water down the carburetor and into the engine falsifying a blown head gasket. So it wasn't really the 1.8 radiator cap and the elevated pressure. Lesson learned.

ya bad idea. if you raise the pressure your raising the temp . they spend a ton of money to designe our bikes to run at a temp for a reason

Bro I have a KTM EXC 125 2T the cap writes 1.4 and I want to change the cap with one with temperature gauge…should I buy a 1.8 or 1.3 cause I can’t find 1.4 cap…please help

I liked the way you did the explanation of the caps, but is there a differance in coolant and antifreeze or is it the same?

Check oil screen behind magnito . Had to rebuildmy bike 3 times after dealerships sold me a rebuild bike . I tried the ho cap bigger rads evrything on the net nothing helped me the screen was blocked with gasket maker.

Hey buddy some great information ,ill have to do some research LIKED ( thumbs up )

Hey there I just watched your video for the first time I just subscribed to by the way! My son has an 04 Suzuki LTZ 400 and has been riding it with no issues and just the other day I noticed steam coming from the engine so he pulled over and I noticed there was radiator fluid coming from where the radiator cap is! And as I was saying he has been riding this thing I would say for at least a week with no problems beforehand he's very experienced and really puts the machine through its paces. I'm just wondering if maybe the radiator cap decided to take a poop?! I'm not sure of the specs for this particular machine but if you could give me any information on this before I go out and buy another radiator cap and potentially get the wrong one. I would greatly appreciate it. Also I noticed the fluid coming out of the radiator was almost identical to the consistency of brake fluid or power steering fluid! And as you might already know radiator fluid has a distinct smell to it and almost a sweet type of smell anytime radiator fluid leaks oh, for me at least I can tell if radiator fluid just by the smell, in this case oh, there was no smell of radiator fluid and again if I had to bet anything I would bet it was brake fluid or power steering fluid?! If this is the case why the hell would somebody put that into a radiator?! I bought the machine for him about 3 weeks ago check the oil I made sure the machine was tight and the radiator Reservoir was full and it was a darker color like radiator fluid should be but then coming out of the radiator cap is this clear liquid which I just noticed yesterday, sorry for the huge rant

I wonder if this would cause pressure to build up and send water out the weep hole though. 🤔

So is it better to have a higher pressure or lower pressure my oe cap is 15psi but they used 16psi which pressure will run my system cooler and what is the point of raising the pressure

Hi mate, i have a kawasaki kx450f and my coolant is leaking when the engine heats, i have a 1.3 bar radiator cap and i use "motul" coolant . Should i use the "engine ice " ? And also buy a higher presure radiator cap? Something like 1.5 or maybe 1.8? Thanks a lot and excuse my english if there are some mistakes :)

As far as thermal conductivity of Evans coolant goes, why dont you test it. Get some Data. Using a stove, a pot, a laser thermometer and a stop watch. Map the temp rise over time.

Hello, i have a gsxr 600 k8, when i come back home from a "fast" ride when i switch off the bike and the fan worked, i hear a boiling sound and then bleeding the antifreeze/cool liquid from the resorvoir, can a bad radiator cap fault? i changed thermostat and agan draining..

yo so i just bought a new rad, since my old one broke and the seller gave me the rad cap aswell, and actually i thought that the thing that it had a spring mechanism and all that was hella weird, since like my old one didnt even have a place for it yet the rad itself did have it, i used the new cap (with the spring and all that) and used coolant that boils at 200c and ive been riding without cooling issues ever since. also my cap says 0.9 on it, even tho it opens at 160c?

What might cause my coolant to leak out after a minute or so of warming up my KX450F?

WHERE can you get these SMALL caps? I purchased a total aluminum radiator on ebay for my 1994 Ford ranger, the factory radiator had the NORMAL U.S. size cap, the aluminum from China has the SMALL cap that looks like the one you have, I want to get a 1.1 Bar cap LIKE what looks like yours, WHERE & WHAT do I ask for, already been to 3 parts stores & they cannot help me.

Did you have any problems with the1.8 cap?

Thanks Great Video 👍

I feel smarter after watching this

May I know if the radiator cap having different size beside bar? Thank you in advance!

But also need to mention to much pressure can blow back in the engine.

my engine boils a lot and drains the water from the radiator very quickly. how can i solve my problem? crf450r 2010?

Also the higher pressure the better the heat soak.

Evans made my bike run way way cooler like 40 degrees

Bought a 2.0 stock was 1.1, thinking bigger is better but now you got me rethinking??

I was riding my 2002 crf450 and we adjusted the idle then the three way hose exploded anyone know why?

Can you answer my question please!!!! I have a 1988 suzuki RM250, what kind of coolant should I use???!!!!

Are utvs allowed in burro wash trail ? I know it had nothing to to with this Video .

Definitely informative

So it is safer to change from 1.8 to 1.1 Than the other way around?

Use engine ice

I had a raptor 700, did the change and it blow out the waterpump seal om my first ride.

I am going back to the 1.1 then, that is true my radiators over heat easier with the 1.8 then the 1.1

you'll blow your hoses off