[Crash21]

I was overheating all weekend at the indiana badlands and am curious why. Some info about it to ponder. Yes I know I was overheating. The hot light was on, the fan was screaming all weekend, and at one point the coolant boiled out of the radiator. I pulled the radiator cap and the radiator is full, as is the res. The radiator was clean as well. It did not come on instantly more like after 1-2 Hours of riding. I was thinking thermostat or water pump but it took so long to start overheating I kinda ruled that out. I had another XX riding with me and he was not having any overheating problems. The only difference between our 2 machines is I have a UNI air filter and a EHS lid. Both of us have stock exhausts with our spark arrestors pulled. The only thing I can come up with is maybe I am running too lean with the filter and lid. I dont have a programmer and I know quads for the most part come pretty lean from the factory. Any ideas? I thought I would get some opinions before I did anything. I really dont want to take it for warrenty and then it not be something broken and get charged a bunch of cash for diagnosis time for nothing.

Please help!
P.S. Some awesome pics and video from the weekend soon to come!

 

[THREESVTS]

What was the air temp? Were you in a lower gear pushing more rpm's than your buddy? Is this the first time this has happened? How many hours are on the machine? Is the radiator free of any mud? I see you have a 13 tooth sprocket. If your friend doesn't he would be running lower rpm's and have a cooler engine temp compared to yours. I've ridden VERY hard all day in 95 degree weather and the fan was screaming non stop, but have never overheated. Boiling coolant is never good. I'm asking how old the machine is because if it's new, there's a possibility that the cooling system had air trapped in it and would cause an over heating problem. I would flush the system and replace it with Engine Ice or something along those lines. Ride it again and see if it happens. If so then a trip to the dealer is in order.

 

[Crash21]

This is the first time it has ever overheated like this or at all for that matter. Temps were in the upper 80s. I was pushing the machine hard/high reving but so was he. We rode roughly in the same gears; I asked him about that to confirm. He has a 13t sprocket as well. The radiator was clear of mud. I have had the XX since Dec and has roughly 60-70 hours on it. I did plan on replacing the coolant with engine ice but I dont want to cover up an underlying problem if there is one. Going to the badlands I end up pushing the XX harder than I ever normally would but like I said he had an identical quad minus the EHS lid and UNI air filter

 

[THREESVTS]

I would say that it's just the high revs and ambient air temp. The fan can only do so much to cool the engine if it's hot out. If the speeds are slower and the revs are high then the problem gets worse pretty fast. It wouldn't hurt to flush the cooling system though. I don't think you're running too lean. The mods you have really don't do much as far as power goes. The air coming in cannot go out any faster then stock with the factory exhaust in place, even without the spark arrestor. Take a look at the end of your pipe and see what color it is. Pull the plug just to be sure.

 

[EEHonda]

I would say you are right, to lean. The pea gravel at the Badlands pulls hard. I ran into the same thing with a stock 400EX about 10 years ago there, it was only 2 months old and it got hot enough that it started puffing out some oil smoke. Filter and proper jetting and never had the problem again. A little bit of fuel can do wonders for your engine temp. Just my opinon.

 

[Crash21]

What should I be looking for on the plug to confirm lean or not? Would I notice anything at this point with a fuel programmer or would it just be a waste of money? I know all quads usually come lean from the factory for emmision purposes but I am not sure to what extent. I plan on talking to Eric at EHS as well to see what he thinks. I appreciate all the input on here and keep the opinions comming. Maybe it's something I didn't even consider. I'm newer to quads but I have a general idea about engines

 

[THREESVTS]

The porcelain part of the plug needs to be a tan paper bag color to be dead on with the fuel mixture. If it's more white it's too lean. More black it's too rich. The EHS lid and a UNI, IMO, won't make you too lean. The lid is barely bigger than the stock opening as far as sq inches go. So the amount of air isn't that much more than stock. If it was that lean you would notice it sputtering and popping in the upper rpm range and your friend would be able to walk past you. I honestly think your problem is just due to high rpm's, ambient air temps, and slower speeds.

 

[Crash21]

I will check the plug today. My only reason to question that it was temp/rpms/slower speeds is that my buddy was riding in almost the exact same way and he had no overheating problem and his fan barely ever came on

 

[Crash21]

Something to add to this now is that I just checked my oil and it was lower. Not by a ton but like half way on the stick instead of full up. I just topped it off as well before the last ride and I dont have any leaking on the ground. I just talked to the dealer he said that was in a more normal range so I dont know. I checked for air in the radiator and there was none. I really dont want to take it to the dealer and get hosed for 2 hours of diagnostic time if they dont find anything.

 

[ein]

the other weekend i ran mine with airbox lid off/ spark arrester out and no fuel programmer and mine seemed to get hot.. moreso than normal. put the lid back on and bike stayed alot cooler! ... just my 2 cents.

 

[THREESVTS]

How did you check the oil? The quick way or proper way? Also checking for air in the rad?

 

[USMC0861]

lean....50 bucks on it

 

[Baxter]

Mine overheated to the point where the header turn blue. One of the things that was wrong is ,I had changed the coolant to engine ice and ended up with a airlock. Only noticed when I had took the radiator of to check it was clean and was refilling it . It took 100cc more coolant. Best way to get rid of air is to squeeze the rad hoses when filling.

 

[THREESVTS]

Best way to get rid of air is to squeeze the rad hoses when filling.

The right way to do it is to remove the cap, start the engine and watch the level. As the thermostat opens the level drops and circulates the fluid. If there is an air bubble it'll "burp" within a few minutes. The air pockets are usually trapped inside the engine somewhere. It also helps to have the front end elevated more than normal so the air can escape easier.

 

[THREESVTS]

lean....50 bucks on it

The reason I don't think he's lean is because he said it happened after 1 or 2 hours of riding. If it's lean it won't show symptoms after 2 hours of riding, it'll be very, very quickly. And his mods are less than a slip on. People on here say they don't get lean to the point of overheating with a slip on and no programmer. The E.H.S lid barely flows more than the stock lid, isn't even considered a performance mod, and there really is no gain other than a cleaner filter. I still think the air temps, slower speeds, and high rpm's is what's causing his problem. Once the engine gets heat soaked it takes a long time to cool it down. If you keep on riding the way you were it'll overheat.

 

[Crash21]

I am almost thinking bad thermostat. I had the cap off the radiator and ran it for a few mins. The coolant ended up rising to the point where it was leaking out of the opening

 

[THREESVTS]

That's normal. It's just pressure and heat making it expand and pushing it out. Keep it off until the t-stat opens and the level will drop. Not only that but if a t-stat is going to fail, 99% of them will fail in the open position. If yours failed closed it would overheat in less than 10 minutes.

 

[EEHonda]

lean....50 bucks on it

I'm with you.

 

[Crash21]

Do you notice a difference in running temp with engine ice? If so how much? I plan on trying the EHS programmer as well both to help it run better and the temp savings. How much hotter will it run if it's just a little lean? The first time it over heated was because of mud in the radiator and it got so hot it came out the radiator. After that happened is when it would over heat with a clean radiator

 

[scuzz]

When I shot this video it was easily 120 with the sun radiating off of the rocks:



When it was stock I lived in Dallas and it was just as hot there where I went riding.

I'd be willing to bet (also) that you're too lean.

(just sharing my experiences)