Thermostat.

Pretty much the XR650R cools off with even at slow speeds while you move, I see L on my dash a lot while I am moving. I have seen as high as 200, but if I turn the fan on (I got a KTM fan installed) it will take it down to 180 or so. One reason to install a dash with a temperature indication/readout (Acewell). I tossed in some Water Wetter, just because I had it laying around. Otherwise I used some pre-mixed Prestone coolant I think it is. I have had no problems as of yet.

Not sure why people are afraid to install the KTM fan, it cost $100, not the most expensive thing out there, and it works *shrug*.

I have 9400 miles on my XRR now and have never touched the cooling system. I have not even taken the cap off to see the coolant. when I look at my overflow bottle I never see the level change more than half an inch. I live in the phoenix Az. area. I am always moving at least 10 or 15 mph at the slowest. Never had a problem. I have thought of replacing the coolant ( with the stuff the honda engineers designed the bike to run with). I have also thought about carrying a spare oem thermostat. I guess I would switch to a stainless one if I knew it was to the same specs as the oem one. These bikes are fine stock. -Matt

If you are in a pinch and just need some liquid to get back to your truck and trailer than even piss will work. it just means you'll have to flush and start again with pure Evans. So stop hitting trees and replaces your hoses before they split!

KTM265 wrote:The prolems with Evans or any other coolant that can't be mixed with water is trial fixes... If you split a hose and lose coolant on the trail...you just cant drop some water in it to limp back in with. If you're not a wrench turner, keep your mods simple and easy to fix on the trail...

I installed a KTM fan on my radiator...When the going gets slow, I turn it on and no problems with overheating.

OK i have read this but still not much wiser now , drill or not that is the question

If you drill, you wont damage any thing,
if you don't, things might not heat up evenly, causing some "hot spots" that could be bad.

Replace the thermostat with one from Napa (#115). Make sure to drill a small hole duplicating the stock T-stat if one's available for reference.
Use Engine Ice ready to use premixed coolant.

Check if the thermostat you buy has a hole in it. Some actually have this in already, with or without a thingy in the hole, a kinda rivet (called "dancer"). If it ain't drill one in, in the rim, say 2.5 or 3mm diameter. This hole allows air to escape hence allows you to 'bleed' the engine, quite like bleeding brakes. But, a main but, this engine has no bypass, so it MUST be able to bleed a bit past the thermostat... so though the thermostat, by means of that small hole!
Do not ride without a thermostat! XrsOnly sells a thermostat which opens 2.5C sooner (seem to remember at 80C instead of std 82.5C), and this is a good thing as the engine starts shedding heat a tiny bit earlier. Also, they sell a rad-cap rated 1.6Bar (std 1.2Bar), and this prevents boiling-over until a higher temp is reached, ie a better thermal storage reserve for your engine.
Never-ever use Evans in your engine, as this stuff has a specific heat of only 2/3's of water hence cannot transfer enough heat hence cannot cool enough.
Engine Ice is good stuff though, for a Focker you think darn well focking straight

You guys are sooooooo old school get with the program all the big boys use this stuff....
http://www.evanscoolant.co.uk/
You won't need a radiator cap just an old sock....

I have an old sock.....

Pure H2O its the best coolant seriously , the problem is that it freezes in cold weather , some people run on destilled water in summer and then change to whatever you like for the winter .

Yeah Maddy, yer right, Mauser is just trying to pull the woolen sock over our eyes.....

Hole drilled , mission complete

I dont have a stock t-stat for reference on the weep hole, anyone have pics of a stock or modified one?

xr650gnar wrote:I dont have a stock t-stat for reference on the weep hole, anyone have pics of a stock or modified one?

Hey how about saying hello before diving in with techy stuff

Welcome to the forums

hi

Whats happenin! Yup, new here, just rebuilt my 2000 pig from the ground up after the 70mph seize up on the freeway last year (I was quick enough on the clutch to avoid going down thank god). What else other than the lower rod bearing! Cracked both case halves.. Now its just broken in and ready to rip! Anyway, looks like you guys are more current than a lot of the other boards so, glad to have joined!

-Adam

Adam, Welcom
You need to go back to the intro site and post some picks!!
We LOVE photos!!!!

my mtr is fairly modded, it takes about 1-2mins to reach normal operating temp, with no thermostat!, ive removed the t/stat housing, run a hi-flow Y joint instead, eliminates the need for uprated w/pump, i do use "anti corrosion type" anti freeze [ its never cold enough round here to need it], i do run twin core chicom rads, plus a 1.8 cap, dont have any overheating issues, even on trail rides following slowpokes, not that i follow them for long, he he, just blast past at first op

I have a '03 XR650R with a brand new OEM thermostat, the left and right Fluidyne Powersports Radiators, CV4 Hose Kit, and Engine Ice coolant. I live in Phoenix, AZ and the bike will reach 200+deg no problem. I have no idea why it gets so damn hot so quick. Even when driving in 3rd gear will the engine temp climb. Anyone know what I can do to fix this issue OTHER than installing a fan?????????
Thank you!

most engines run with coolant temp of around 200 degrees normally(212 is boiling point of water), when i ran my mtr stock it would boil if caught behind slower riders on the trail, i found once i got a hi pressure cap this stopped it from ejecting the coolant, never had a problem from it runnining too hot, since i modded the mtr i removed the t/stat housing and installed chicom twin core rads, it gets to operating temp fairly quickly, plus our normal air temp is always above freezing so no worries there, also a 50/50 mix of coolant shouldnt boil till 250 degrees , so dont stress about it

This is what I run for thermo(took the brass dancer so it was just a hole) and coolant with stock cap and haven't had any boil overs even in tight slow stuff in hot humid weather! (just thought I would share)

http://www.ebay.com/itm/190660510441?_trksid=p2060778.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Sorry pic is sideways @#$%&*iphone have to figure that out! 

Just to clear one thing up about EVANS.....your engine will actually run hotter than with ethylene glycol/water mixes
A lot of people get confused and think EVANS cools better, It doesn't, it simply tolerates a higher temperature without boiling off. so if the slightly higher temp is ok for your engine, then its safer to use

I run " Engine ICE " in the piggy , with the stock rads , and it works well , oil temperature is at 150 Fahrenheit , that is the lowest i have seen on a xr over here , they usualy sit at 180 degrees F .
BUT , i am going to dump it soon as the talk out there is that because it contains small silica particles to clean blast the cooling system it also damages seals and other bits , so i only want to run it for short period of time to clean the insides and then put some normall water based coolant in for piece of mind , when i get the fluidynes rads .

Pathfinder wrote:Just to clear one thing up about EVANS.....your engine will actually run hotter than with ethylene glycol/water mixes
A lot of people get confused and think EVANS cools better, It doesn't, it simply tolerates a higher temperature without boiling off. so if the slightly higher temp is ok for your engine, then its safer to use

Correct .

I just use what the book states...no heating problems @ 40mph ?......you lot must be riding everwhere in 3rd...try changing to 4th then 5th

Mad Frosty wrote:

Pathfinder wrote:Just to clear one thing up about EVANS.....your engine will actually run hotter than with ethylene glycol/water mixes
A lot of people get confused and think EVANS cools better, It doesn't, it simply tolerates a higher temperature without boiling off. so if the slightly higher temp is ok for your engine, then its safer to use

Correct .

Umm, yay & nay. Yeah, it definitely will run hotter, but what does Pf mean with "slightly hotter"? Besides, what about marginal situations, tight slow singletracking with little wind through the rads? The temp will soar but the rider will be blissfully unaware of it because the stuff does not boil off... which ain't good for the engine!
Water please, with some glycol added >> called coolant, sold the world over! Cools best, protects so well it is OEM-prescribed by all manufacturers bar none, and is cheap enough too.