FINALLY fixed the overheating problem with my 05 KTM 450EXC

[Marcelo T]

Can some one explain what has the jetting anything to do with Overheating?

[MikeSD]

if you are jetted too lean it creates more heat, and can blow the motor.

rich is safer and cooler, but less power and less mileage.

[cbff33]

I had the same problem, first ride out, smelled antifreeze, solution.....GRAB WHAT GOD GAVE YOU AND RIDE THE DAMN THING. Have not had a problem since. If you can't do that, go get an aircooled crf aka xr100

[cbff33]

Oh my, I am out-classed. I don't even have a "resume".

One last time for you, Scary, I never "spouted off" about how I ride and where I ride. I explained WHERE I ride because it is PERTINENT. It's the TIGHT AND NASTY TRAILS that make the KTMs overheat. Get it? And I never said that 95% CAN'T ride these kind of tight trails, I said they DON'T ride the trails. It's a choice for most people NOT to ride stupid sick trails. The group I ride with happens to like it. My challenge to Patrick was a counter to his claim that I am slow. My offer remains to prove to him otherwise.

Contrary to your belief that I came here simply to BASH a bike, my "entire point" was to say that during very tight trail riding the KTMs I ride with are having problems with overheating. But a few of you guys simply don't want to hear anything bad about KTMs, no matter what. That is BRAND LOYALTY, whatever you say you ride.

I think you can find the "educational value" you were looking for. Check out the suggestions that explain how to put a fan on your KTM if you'd like to keep it from boiling over. If you ride a KTM on tight nasty trails, I would recommend it. Feel free to take that advice or leave it.

Unless you have something pertinent to add, I'm done. Later.

Again, I ride tight, rocky, wooded trails, AND I do it all over 9000 feet. there is far less air up here for cooling. You just gotta ride faster. You will realize it when your Honda starts boiling over just like your KTM did.

[jeb]

Does thinner oxygen air cool less efficiently? It could be, I'd just never heard that.

[jeb]

I had the same problem, first ride out, smelled antifreeze, solution.....GRAB WHAT GOD GAVE YOU AND RIDE THE DAMN THING. Have not had a problem since. If you can't do that, go get an aircooled crf aka xr100

I guess if you ride in open stuff all the time, that'll work. Many of us like to ride in single track, though.

[cbff33]

I guess if you ride in open stuff all the time, that'll work. Many of us like to ride in single track, though.

I don't have any open stuff, unless you want to consider the single track that is above 11,000 feet and above timberline as clear, and at that altitude, dirt doesn't really exist...its all boulders. The colorado rockies do have some trees here and there. but not too many. since the state was cleared of all forests by the timber industry, trees are hard to come by here. Now they are working on crushing all the rocks on the states single track trails to use as roadbase for all road projects nationwide. But I don't know how much more they can do to make the riding here more "open stuff" than what it already is. Maybe they can consider leveling all the mountains here to really help give more of a true "open stuff" feeling. Wouldn't that be awesome....the future of colorado riding,,,no trees, no rocks, no grades to contend with, just nice flat riding...better put the bike on ebay so I can get a gsxr 1000. If all that happens, maybe the pros will like having enduro races here in Colorado.

Truthfully, the only open riding that isn't single track around here, is the 2 miles I ride down the highway to access the national forest.

[obgod3]

Jeb, now that you've moved down to Arkansas just wait until a 102F day and go play endless log hopping on some of the single track down there.

That will really give you and the bike a workout. It might even overheat some. ?

Are you anywhere near Fayetteville? We ride White Rock all the time. ?

your wrong about CO, where I ride 102 is quite normal during the summer here, never overheated. Same for Utah, but in western CO 102 aint nothin.

[Durango_Dave]

Does thinner oxygen air cool less efficiently? It could be, I'd just never heard that.

It seems to me that perhaps its the drier air out west that contributes to overheating more than in humid climates. ? JMHO

[chrispy]

? Ya mine did the same thing till I replaced the radiator cap and zap it quite sraying steam.

[g.thumper]

All right, enough is enough! Lets get to the nuts and bolts of this discussion. I see it has gone on long enough I hope. What have we learned so far? There are those who swear by and some who swear at KTM's because they reportedly overheat. My question to the board, How do we solve the problem? Let's not piss and moan anymore lets find a solution.

Where do I begin? I recently purchased a brand new '05 450MXC and on the my very first outing I noticed a stream of green liquid I recognized as antifreeze running down the front down tubes. I shut it off and checked the fluid level in the radiator. I let it sit for about 30 minutes while I attended to wife and sons needs. I then started it again and rode it around camp for 20 or so minutes. I came back to the truck when I noticed the green fluid was running down the frame again and out the water pump weep hole. It also appeared to be leaking at the Y-pipe up under the gas tank. Enough of this nonsense, I loaded it up and carried it to the house. I ordered the KTM cooling fan kit the next day. I installed it before I took it out again, also checking the hose clamps and replaced the factory juice with Engine Ice. I also notice the plastic elbow attached to the radiator overflow hose was not pushed into the frame as it should have been. This explaines why the green juice didn't run inside the frame neck and onto the exhaust header. Last weekend I took it out to check out my handy work and to get some more time on the engine. I rode it a total of 2.2 hours including what I had already ridden the week before. When I loaded my bike up I noticed the left side of the engine appeared as though the gasket between the block and cylinder could be leaking. It looked wet, possibly oil had been leaking from the head and running down the side of the engine. We headed straight to the dealer to have them inspect. They suggested I leave it with them because of the short amount of time I had left on the warranty. I found out this past week they traced it to the water pump seal leaking and running out the weep hole and down the side of the engine giving the look of possible gasket leaks. I'm currently awaiting parts so the dealer can make the repairs. Unfortunately by the time I get to ride it again it will be out of warranty. I sure hope this is going to fix my problem or I'll have even a bigger problem than overheating. I realize I don't have a solution for your reported overheating problem but I hope to get to the bottom of it soon. Has any one used the KTM coolant recovery tank?

[Cactus73]

All right, enough is enough! Lets get to the nuts and bolts of this discussion. I see it has gone on long enough I hope. What have we learned so far? There are those who swear by and some who swear at KTM's because they reportedly overheat. My question to the board, How do we solve the problem? Let's not piss and moan anymore lets find a solution.

Where do I begin? I recently purchased a brand new '05 450MXC and on the my very first outing I noticed a stream of green liquid I recognized as antifreeze running down the front down tubes. I shut it off and checked the fluid level in the radiator. I let it sit for about 30 minutes while I attended to wife and sons needs. I then started it again and rode it around camp for 20 or so minutes. I came back to the truck when I noticed the green fluid was running down the frame again and out the water pump weep hole. It also appeared to be leaking at the Y-pipe up under the gas tank. Enough of this nonsense, I loaded it up and carried it to the house. I ordered the KTM cooling fan kit the next day. I installed it before I took it out again, also checking the hose clamps and replaced the factory juice with Engine Ice. I also notice the plastic elbow attached to the radiator overflow hose was not pushed into the frame as it should have been. This explaines why the green juice didn't run inside the frame neck and onto the exhaust header. Last weekend I took it out to check out my handy work and to get some more time on the engine. I rode it a total of 2.2 hours including what I had already ridden the week before. When I loaded my bike up I noticed the left side of the engine appeared as though the gasket between the block and cylinder could be leaking. It looked wet, possibly oil had been leaking from the head and running down the side of the engine. We headed straight to the dealer to have them inspect. They suggested I leave it with them because of the short amount of time I had left on the warranty. I found out this past week they traced it to the water pump seal leaking and running out the weep hole and down the side of the engine giving the look of possible gasket leaks. I'm currently awaiting parts so the dealer can make the repairs. Unfortunately by the time I get to ride it again it will be out of warranty. I sure hope this is going to fix my problem or I'll have even a bigger problem than overheating. I realize I don't have a solution for your reported overheating problem but I hope to get to the bottom of it soon. Has any one used the KTM coolant recovery tank?

First of all, if your jetting is stock, it's too lean. Log on to KTM Talk to get your jetting sorted out. After you get the water pump gasket fixed and have the jetting squared away, you will likely find the end of your overheating problem. Putting engine ice in your bike and an electric fan will just treat the symptoms without fixing the problem. After you get your bike back, jet it, take the fan off, and put the stock coolant back in it and go riding. I bet it doesn't overheat anymore. Unless you ride in extremely gnarly, tight, slower than 8 mph stuff, your bike shouldn't need the fan.

Don't sweat the warranty running out, KTM is pretty good about fixing stuff under warranty, even after it expires, especially if it's related to your water pump gasket leak.

The oil weeping between the cylinder and the head is normal and will stop when you get a few more hours on your bike.

There is a guy on KTM talk selling coolant recovery tanks, but just like the engine ice and fan, I don't think it's necessary.

[lost coyote]

I just bought an 06 450xc and have had no probs so far, I love it. I made the jump from the honda's. This bike is good all around,even on the track. I see more and more every weekend in the district 37 races here in SOCAL. ?

[Shrewless]

Enough! You don't need cooling fans, oil or antifreeze additives, or any other crap. Make sure the radiators are not overfilled, rejet the bike for your altitude and temp, and if you want to be more cautious then jet a little rich. End of story. If you can't get it work to your satisfaction after this then buy a different make and sell me your KTM at a great discount because we all know they are junk so I would be doing you a favor taking it off your hands. I have to unsubscribe from this thread cause it is filling my mailbox.

[g.thumper]

No way, I'm not selling my KTM to you or any body else. I bought it because of the reputation and power this bike has. I just want to get it up and going so I can break it in, change the oil and have fun with my young son. The fan will stay for now. Your probably correct in regard to not needing it but I do ride some trails slower with my son right now. In the future he will be waiting on me but for now I'm still in the lead.

[impi]

Our state used to allow the KTMs to be plated cause of the way the title reads. But now the only way our dealer will plate a bike is if it comes set up for the street which both the Gas Gas models do. The 05 EC300 and the 05 450 already have everything they need to be street legal and the dealer will plate them on the floor for us. This is the same dealer I bought my 04 525EXC from and they plated it from the floor even though it was not street legal. They left the legality up to me. They will no longer do this for their KTM line cause of State scrutiny.

Not sure which dealer you're using but the 450EXC I bought a month ago was plated by the dealer without any problems. Fitted the DS kit and quite happy with it.

[ractive1]

well i think staying off the clutch is the key, and also proper mixture of coolant. ive raced

and rode some tight trails and never over heated my bike.but theres always a first.cant wait to take it on the big bear trails, and creekcrossings. i just got a 06 525EXC and it is bitchen.

[cardiffdrz]

well i think staying off the clutch is the key, and also proper mixture of coolant. ive raced

and rode some tight trails and never over heated my bike.but theres always a first.cant wait to take it on the big bear trails, and creekcrossings. i just got a 06 525EXC and it is bitchen.

Congrats on the new bike. Splice will not be missing his KTM as by now i bet he is an expert at valves with his Honda

[mophead]

I've never had a problem with my 450exc overheating except when I'm on the clutch too much, or ride too slow

[DR.billZ]

Never had a problem with overheating and I ride EXTREMELY tight trail in the hot, humid Southeast.

Doesn't overheat in 3 trips to Colorado either.

You've got TO KEEP MOVING.

One must ask oneself one question:

Do I want to have a slight overheating problem or adjust and replace valves all the time