overheating problem

[WheelieMan4]

I have an 05 450r that I do mx with. Everytime I practice, or run the quad hard for over 20 mins, my coolant actually starts to boil!?!?!? My fan runs fine, and is clean, the radiator is clean...I have to add coolant everytime before I ride. And when I ride, even if it doesnt boil, the coolant still runs out all over everything and makes a mess and smells horrible.

Im out right now with a broken arm and decided to ask you all and see if I can get this problem fixed before i'm able to ride again...Thanks

[TheBlasterMan]

Ive been in your situation. My problem was jetting, mine was running lean, yours probally is to.

When u say the coolant flows, what is it flowing out of?

[WheelieMan4]

It's coming out of a hose, so i'm guessing its the overflow...My jetting seems to be good though? But I guess I could be wrong..

[allstock]

what kind of coolant are you using.... i used to use normal prestone and it would boil then i tried coolanol and engine ice and neither would boil... also you should invest in a temperature gauge

[WheelieMan4]

Yea..its regular prestone 50/50 crap from wal-mart...I guess I will have to try some engine ice...

Where can you buy engine ice? And a temp guage..are those the strips to put on your motor? Where do I get that at as well?

[Rulz]

Originally posted by WheelieMan4
Yea..its regular prestone 50/50 crap from wal-mart...I guess I will have to try some engine ice...

Where can you buy engine ice? And a temp guage..are those the strips to put on your motor? Where do I get that at as well?

http://cgi.ebay.com/ebaymotors/TEMPERATURE-GAUGE-YFZ450-KFX450-TRX450-RAPTOR-660-700_W0QQitemZ320140432140QQihZ011QQcategoryZ43977Q QcmdZViewItem

[TheBlasterMan]

i still managed to boil engine ice. My issue was the jetting. Putting engine ice in may solve your problem.

I dont think its right if its overheating from 20 mins of hard riding. Id give your jetting a second look.

[WheelieMan4]

You think its to lean? What should I go with...I have a stock motor, full rossier, and a uni filter with no lid....Thanks

[TheBlasterMan]

Its very hard to give someone exactly the right jetting. Too many variables come into play like elivation, and other riding conditions. Your probally very close to the right jetting. Id just bump up the main on what ur running now and see if that improves your running temp. You may even notice a small gain in power.

It may not even be the jetting, but that is what i would look at first. You might just ride like a bat outa hell. But in my opinion its better to be safe then sorry.

Average starting point is around 185 main jet. Piped open lid 05 450r's usually run 175-185 main. Ive noticed Rossiers tend to fall around a 180 mj.

Bump up the main, its trail and error.

my $.02

[pro-rider46]

yeah invest in a jet kit if you havent already, i was running a 180 and seemed a little lean and now i am at 190 and is good on 90+ degree days so i am going to a 185 cause its on average like 80 degrees.

[TheBlasterMan]

make sure u stay with keihin jets. Dyno jets are on a different scale and from what i hear dont go as wide as keihin. A scale many arnt familier with including me lol

[pro-rider46]

i have a scale i can post up tomarow. for a 190 keinen its like a 170 dynojet. if you have the conversion chart it is easy to get right

[pro-rider46]

yeah the chart is in the the how to section under "how to jet your bike�h

[WheelieMan4]

Thanks...I bought this quad used and have never tore the carb apart yet...but from what I remember, the guy said he had a 178 main in it...I will have to get in there and see, thanks a lot.

[TheBlasterMan]

no problem :cool:

[WheelieMan4]

Turns out it has a 182 main jet...you still think it's lean?

[duke416ex]

I have had 2 overheating issues, one time it was old coolant. I just put new engine ice in and it was fine from then on.


The other time was similar to yours, if you weren't riding hard it wouldn't overheat, but in a rce it would spew out. I talked to other who had similar problems and tured out to be a blown head gasket.

[TheBlasterMan]

182 sounds about right but dont take my word for it.

Make sure radiator is clean of debris like mud and dirt.

Change coolent, many prefer engine ice.