What is the average oil temperature of a fully warmed up and ridden 400EX? What temerature is too hot and could be dangerous for the quad? Thanks!

 

Not sure on the 400EX but my bikes use the same style engine.( XR 250R ) On a 105 degree day we had a hair and hound race. the trail was super tight single track threw the woods. alot of tight turns that you come out of in 1st gear floored up huge hill's. never got it into 3rd so the engine got super super hot. I was loosing power, hickuping, pretty much running like choke was on. my ankle got bunred by the clutch cover. when i got back to the camp my mom's meat thermometer read 300 degrees! Darn good thing for the snythtic. Joe

 

never really answered your question did I? id say to keep it below 250 with snythtic and 200 with normal oil. Those RFVC engines run hot. Your wont hurt it so dont worry I have only lost 2 engines and they were due to stupidity.. XR500R in the sand with Havoline 30WT and a big red pulling 1,000 lb trailler up a 5 mile long hill floored in 2nd low range Keep fresh oil in it and it will litterly run forever..

 

I'm running around 150-225 this time of year.Curtisy of oil temp dipstick.

 

Oil temp dipstick? where can i pick one up? sounds like a life saver to me..

[This message has been edited by JRM (edited 11-12-1999).]

 

White Brothers has them, they referred me to East Coast ATV, it was $44.05 with tax and shipping costs. There number is 215-529-4632 .

 

Thanks!

 

We build racing 4cyl.4 stroke engines for a living and find that one of the biggest problems with oil temp. is using the engine hard when the oil is too cold. (oil cavitation/starvation problems etc.) I have an oil temp. gauge fitted to my Polaris Scrambler 500 and find the it takes 15 mins to get the oil temp. up to 40-50 degrees Centigrade (minimum temp. to use engine hard).
In tough 'woods' hare & hounds races the oil gets up to 70-80 degrees Centigrade. We know that the oil works well up to 130 degrees Centigrade. I did a beach race recently and found a big problem getting the oil hot enough the whole way through the race so I'm working on a water to oil type cooler to warm the oil as well as cool it.