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'08 300xc overheating

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Took the trusty steed out for its first ride this past weekend, what an awesome ride except for any long uphill pulls and the darn thing would overheat. I am running engine ice in it thank god its environmentally friendly as kamloops has been well drenched... Now I never lost a lot of fluid but I did have to go back and top up. I did buy a brand new rad cap ( stock 1.4 ) and it still overheated.... should I replace the impeller, I am old to biking but new to the new bikes as in I haven't ridden in 12 years, my old RM400 didn't have rad!!! I have also heard that it could be the rad protectors that restrict the air flow, could it also be I am using opti 2 fuel mix which I am running it a little richer then what was recomended ( I was told their mix was 100:1 ) which kinda scares me! Its probably about 80:1 which my friend is also running in his 300XC-W...... I am not an extremely fast rider but I can keep up so I don't really think that too slow speed and low air flow would be an issue. Any help would be great!!!!!!

:banana:

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really depends on where your jetting is currently. If it's close and it gets cooler, then you could go too lean. or you can be lean in one section of the circuit.

Need more info, jetting specs, etc.

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The 300 is prone to overheating......more so than the 250.

I thought that the '08 bikes came stock with a 1.8 cap. If not, replace the 1.4 with a 1.8 cap.

After proper jetting, the best fix is a radiator fan. A factory fan kit is available for the E-start 2 strokes.

Also, some radiator guards restrict the air flow too much.

Do a 'Search' on this problem. Also, join KTMTalk if you are not a current member. There have been several lengthy discussions over there on this very issue.

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really depends on where your jetting is currently. If it's close and it gets cooler, then you could go too lean. or you can be lean in one section of the circuit.

Need more info, jetting specs, etc.

I started out the day with a 168 jet changed it the next day with a 162 and still had problems....

I was told to try taking out the thermostat and if it still over heats it then could be my pump/impeller that isn't working.... is it okay to run with out a thermostat????

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by dropping the main size, you made it leaner and likely to overheat worse. Luckily most overheating issues come from lower throttle openings and lower speeds, usually climbing hills. Fuel has a cooling impact on the engine, so actually being a little rich helps, typically.

Taking the T stat out actually hurts also. the water moves thru the system too fast to be efficiently cooled.

what needle, pilot, AS setting, clip position?

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I never lost a lot of fluid but I did have to go back and top up.

Maybe your radiators were overfull to begin with?

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If your water level is at the bottom of the radiator neck , it is to full. Keep it just above cooling fins, with mine set like that never any problems.

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What is your definition of over heating? A little blow off or steaming like a tea pot. Is the radiator over filled (you just cover the core) if so its going to blow off until it reaches the right level. Jetting, tire selection and air preasure, and rider skill level all contribute to a bike getting hot. Bottom line if you are reving and not flowing much air it will get hot, so put a recovery bottle on there that way you have a sealed system and the bike can get hot all it wants.

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It is pretty common for my 08 300 to spit some coolant and on nasty climbs shoot steam. I have put the 1.8 rad cap, moved up from a 35 to a 38 pilot jet. I have a XC so there is no thermostat. I keep my main jet at 160-162 with a 50:1 mix, but I keep it there because my sparkplug looks good there. After a little more then two years with this bike I have come to accept it. I just make sure I have enough fluid in there before I head out. Your best bet would be a over flow tank or getting some of the Zip-ty waterless coolant.

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The 300 is prone to overheating......more so than the 250.

I thought that the '08 bikes came stock with a 1.8 cap. If not, replace the 1.4 with a 1.8 cap.

After proper jetting, the best fix is a radiator fan. A factory fan kit is available for the E-start 2 strokes.

The best fix is to speed up, lol. 2008's definitely came with 1.4 radiator cap. 2009 or 2010 switched to 1.8, so that would be my first suggestion.

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I have a 09 300 XCW and have done most of the overheating mods....overflow tank, 1.8 rad cap, engine ice, adj jetting and still overheated on most outings until I installed the radiator fan. I believe the problem is solved.

Is a heavier duty Stator required for the use of the fan???? I saw the heavier stator and under the description it read: For use with Heated Grips, HD lights or radiator fan.

It would seem to me that a little fan like that wouldn't draw that much power, but I don't want to install the fan myself if it requires the stator at this time.

As for the 1.8 cap, My 09 came with the 1.4 and I replaced it with the 1.8.

I'm also looking into installing the CRT to catch any possible overflow. Some of my club rides are pretty long and I don't want ot be adding creek water, piss or anything other than what's in there to begin with.:banana:

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So the trials and tribulations of owning a bike.... I went to the dealership and asked for a 1.8 rad cap... the guy says ktm doesn't make one and give me a 1.8 cap that will work.... I opened it up at the dealership to look at it and told the guy that this was too small of course he said no its what he's been selling to all the KTM guys that have been coming in looking for one.... well I got home and sure enough I was right..... the spring was to short when compared to the stock cap. Of course it screws in but I don't honestly think the spring would seat the seal to the rad. I will take it back ... Does any one know if KTM does make a 1.8 cap. If not will any of the other manufacturers make a cap to fit.....from todays experience the Kawi doesn't fit.

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Lot's of good suggestions here. You can also do a search for this topic, it has been beaten to death. Overheating the 300 is a common problem, but there has been some creative ways to overcome the issue. There has even been some fantastic fixes with pictures here.

(I still miss Chaz. Scout out all the single-track up there so you're ready when I show!)

I would overheat almost every ride. I finally broke the Y in the radiator hoses and ceased the beast when she ran outta water. :thumbsup:

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The problem seems to be that the radiators are too small for our bikes.

I see 250's with larger radiators.

The best fix is fans! I installed a dual set up. Cost me about $30.

IMG_1569.jpg

IMG_1568.jpg

But also if you look at our shrouds, the lower side doesn't allow much air to flow through.

IMG_1853.jpg

You might want to trim off the area I highlighted in yellow:

shroud.jpg

I haven't trimmed that area because I have dual fans and the CRT made by RLR.

But you might want to try this.

Good Luck!

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Where do you pull the power from and do you run a light with your fabed up computer fans?

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Where do you pull the power from and do you run a light with your fabed up computer fans?

I go directly to the battery, I upgraded the battery to the YTZ7s which puts out 130cca

I have a light but I only put it on when I plan on riding at night. I don't want to bang it up for no reason, so I don't leave it on the bike.

These computer fans draw a fraction of the KTM hardparts fan. Both fans don't even come close to 1 KTM fan power consumption. And each fan moves 102 CFMs so that's a lot of airflow! 1 fan draws 9 watts of power. Which is really small.

Edited by KTM300XC-W09

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So then you have it on a switch? And where do you mount the switch? What switch?

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