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overheating issue

Posted: Fri Mar 22, 2019 1:47 pm
by CHAPO450X
Hi all, hoping some one can help with an overheating problem I have with my CRF 450X 2010. I've had this bike quite a while and never had a single issue with it. On my last 2 rides the bike overheated and dumped a lot of coolant out of it. The first time was at the top of a difficult hill - enduro and the second time when i was doing a lot of waiting at idle riding with my daughter. I assumed after the second time i had a cooling system issue . After doing a bit of online research everyone who has a problem like this heads for jetting or exhaust changes, not one person even mentioned the cooling system ! I found this odd but it did get me thinking , I noticed after the last ride before the heating issue that i had damage to the header pipe where it bends around the engine. It must have coped a hit and it was slightly kinked directly after it leaves the engine . I'm not sure when i did this and did not notice a performance change. Maybe just a coincidence but it is the only thing different about the bike. The bike is completely stock, I love it the way it is! has anyone had this problem ? Can anyone help me ?

Re: overheating issue

Posted: Fri Mar 22, 2019 7:54 pm
by JimDirt
Welcome the the site !! \:D/

You mention you have had the bike quite a while , how long ?? , and what have you done to it ?? (maintenance wise/rebuilds/head gaskets, etc.)

Have you tried starting it from cold and removing the radiator cap ?? , you need to do this to see if there is air bubbles going thru the system indicating a blown/leaking head gasket or to make sure your impeller shaft in the water pump is not leaking , also look closely at the radiator cap itself , and make sure the seal is not compromised ..... running hills and sitting idling WILL make the bike overheat , why ? , because the only cooling is the air that flows thru the radiators , so when you are sitting there , its got no air flow or anything to cool the water that is flowing and it will overheat or spew out .....

Have you considered a cooling fan ?? , I made my own setup Image Image , but Trail Tech makes a nice setup that is basically bolt on
https://www.crfsonly.com/catalog/produc ... ts_id/5360 , and switching to a 1.6 or 1.8 bar radiator cap will allow the temps to raise about 50 degrees before it starts to boil over

Also switching to Engine Ice (what I use) or Evans Waterless Coolant will help with overheating https://www.crfsonly.com/catalog/produc ... ts_id/1920

As far as the exhaust goes , it might help if you could post a picture of it , so we can see whats going on , or if its anything to worry about .... to post a picture you need a image hosting site like IMGUR or , if you have money , Photobucket (it used to be free to but they got greedy and lost a lot of people) or any image hosting site to use for Forums , for IMGUR you will sign up (its free) then upload your picture/s to it , then click on the picture and it will open up a little window with the picture and some links on the right , click the one that says "BB Code (message boards & forums)" its second to last on the bottom right , it will look like this ............................................ [img]https: //i.imgur.com/yLR1FNo.jpg[/img] , then just Copy , then Paste that code in your post here

But it will show up like this when you hit Preview or Submit
Image

Also , make sure your jetting is correct for your elevation , if the bike is stock , then most likely its lean even if you are at sea level , you need to check the main and pilot jet and see what they are , if its stock the pilot will be a 42 and that is too lean , the main will most likely be a 142 , which is too lean (this is stock jetting made to pass emissions , not run well)

This is a Jetting Guide , if its jetted to this , it should be good , and that will eliminate that as a cause or issue

Jetting Guide for Main Jet:(pilot 45) CRF450R/X

Sea level....165
2000 ft.......162
4000 ft.......160
6000 ft.......158
8000 ft.......155


Temperature/Elevation:
One main jet size (up/down) for every 2,000 feet or 25 degrees in temp.

Re: overheating issue

Posted: Sat Mar 23, 2019 1:06 am
by CHAPO450X
Hey, thanks for the reply . I did as you suggested and ran with the cap off from cold , I was a bit surprised to see the fluid level was full after it dumped some on the last ride . I ran on choke for about 30 seconds then let idle to about 2 minutes . At this time the coolant was too hot to hold your finger in , the header was radiating heat and you could barely hold your hand on the muffler. Surprisingly the exhaust air itself felt quite cool. I have had the bike about 7 years and other than oil and filters , I have not changed a single thing . Im pretty sure the original owner hadn't either. To describe the header kink without a photo , id say a quarter or less of the pipe is restricted , but the hit was enough to push it back onto the original plastic engine/waterpump guard and melt it . It was this smell that made me realise the damage . The header now sits about 5mm off the frame. There is no damage to the header where it must have taken the hit, only where it bends straight out of the block. I never took any notice but maybe this has always had a slight kink at this point from manufacture ? I like the look of the fan you have , do you have it one side or two and i take it its thermostat controlled ? Auto on - off ? Its just got me beat on why its doing it now and has never done it before. Nice looking bike you've got anyway , I haven't seen a seat like that before with the dip . Custom made ? Cheers Dave

Re: overheating issue

Posted: Sat Mar 23, 2019 2:44 am
by Leardriver
A CRF getting hot after a tough section doesn't necessarily mean that anything is wrong.
You could be pretty lean if you are truly bone stock, like Jim says.

Re: overheating issue

Posted: Sat Mar 23, 2019 8:42 am
by JimDirt
Leardriver is correct , he is our resident Carb/fuel guru , he is actually the one that came up with the jetting chart I posted above
I am wondering since you said its pushed back that you may have a exhaust leak either at the head where the header connects or where the header and muffler connect , also , when you let off the gas , especially on downhills or for extended periods , does it pop/backfire thru the muffler ?? this is a good indication its too lean , not sure why it decided till now to overheat , it could be header related , but it just might be the coolant has become diluted or just wore out (you need to replace coolant periodically anyway as it breaks down just like oil does) , maybe its just now that you actually noticed it ??

As far as the fan goes , it is only on the Right side , and yes , the second picture is the thermostat control sensor , it kicks on/off the fan as needed just like a car , the switch is actually from a car , here is a quote of my post (below) from 2013 on parts used (pics don't show up because Image Shack decided to charge as well, but I could dig up my original pictures of the wiring , etc. if you would like) , though the Trail Tech fan (and Honda makes one for the 250X that will fit as well) are a easy install and will benefit you if you ride in any single track or stop and go places along with the 1.6 or 1.9 bar cap (stock is 1.2) and Engine Ice or Evans , it all adds up along with the correct jetting (follow the chart recommendations) , here is the entire topic https://www.crfsonly.com/forum/viewtopi ... ooling+fan
Parts:
SW524 Cooling Fan Switch ...AutoZone ...$32.99
Spal 4" 12v Pull Cooling Fan...EBay........$35.99
12v 2 prong male/female connector ...RadioShack....$5.99
Shrink Wrap ...RadioShack..$3.49
ATC Splash Proof Fuse Holder..AutoZone..$3.29
and about a 4' peice of wire i had laying around , i went a little extra and added some 1/4" split loom wire wrap , i got that at Shucks/O'Rielly Auto ..$6.99
So for roughly $88.74 i got a cooling fan that turns on when the temp gets too hot at about 195 then shuts off by itself at about 180

On the Thermo Switch , just go to AutoZone and give them that SW524 part number and they should be able to find it , i think its for a Mitsubishi car , i just cant remember its been too long

PICTURES:
Here is my setup , i got the fan from EBay (its the same fan KTM uses) its a Spal Pull Fan http://www.ebay.com/itm/ws/eBayISAPI.dl ... 0932579727 , it needs to be a pull fan not a push fan as it needs to PULL air thru the radiators , the switch is off a car , its a fairly straight forward install , also i would highly recommend getting a 1.6 or 1.8 radiator cap , and Engine Ice instead of coolant , it alone will drop your engine temps by 50 degree's here is a basic jetting guideline to go by for Main Jet

Sea level 165
2000 ft.. 162
4000 ft.. 160
6000 ft.. 158
8000 ft.. 155

Image
Image
Image
Image
Image
Image

The benefit is no worry about overheating and being stranded with no coolant or worse a blown head gasket 30 miles from your rig/camp

Re: overheating issue

Posted: Sun Mar 24, 2019 4:12 pm
by CHAPO450X
Hey, thanks for the advise. I have decided after an awesome of 7 years without touching a thing - maybe its time i did ! Mind you the bike only has 60hrs and 1750k"s on it. I will look at the jetting and maybe replace the header with a stainless one, does anyone know what these power bomb things are like ? I will also go over the cooling system and replace fluid with the blue ice, ive never thought to renew the fluid .Its quite funny how things have turned out, when i got this bike stock as a rock I said to everyone im not touching a thing its staying factory stock because i just want a reliable bike i can get on and know it will start and run. Now you mention things like emission control and having to comply to certain standards or levels , I think I see whats going on . I was of the opinion that who am I to try and improve on Honda's vast history and knowledge of bikes and performance , and that what came out of the factory was the best possible set up ! Things aren't always what they seem, there's always red tape. Its time to let her breathe ! I will post the outcome . Thanks again - Dave

Re: overheating issue

Posted: Wed Mar 27, 2019 9:32 am
by JimDirt
I am still using the stock header , but have a 450R(05) muffler on mine with a Pro Moto Billet end cap on it , it helps with performance and is not annoyingly loud like a aftermarket muffler is , as the OEM muffler still has to comply with noise limits , but it helps the engine breath along with removing either the snorkel or complete top from the airbox (the part you see when removing the seat) and rejetting for your elevation , you can even do the "Pink Wire Mod" if you want , it will hurt nothing , and is easily reversible (or you can put it on a map switch like I did) it will give the engine 500 more RPM before it hits the limiter , and give a bottom end performance increase , it is better noticed when using a different cam (I use a HotCams stage 1 in mine) , the mods I just mentioned (along with Stainless intake valves) is all that has been done to my X mechanically , mine is still on the original piston,clutch since new and it has about 3600 miles on it (never kept track of hours but am guessing around 150 or so *mostly single track*) , yes , keeping it less modified is better , as it lessens the interval between major maintenance chores , the "recommended" maintenance intervals (piston, etc.) is based of "Racing Conditions" , not light use , so these bikes will last a long time if maintained properly (oil changes , dirt , etc.) , I have had mine since new (June of 05 , and its a 06) and have not had a major malfunction with eh exception of the intake valves about 6 months in , before I learned about dirt getting past the air filter taking out the valves

Other than that , my bike has had a happy life of minimal malfunctions , and I like it that way , the 4 stroke high maintenance myth , has been debunked long ago ....

In relation to your reply , don't forget to add/swap the radiator cap with a 1.6 or 1.8 bar , it will lessen the chance of overheating under normal conditions

Re: overheating issue

Posted: Fri May 31, 2019 6:53 pm
by Crfroe
Howdy all, not sure if this is relevant to this topic, but I got my 05 crf250r back together today and started for the first time. Let it idle for a few minutes to see if it ran ok, like didnt die and what not, and I notice that the exhaust was glowing red right where it bolts up to the head, it has an fmf power bomb and q4 muffler. Just want to know if this is normal, or if the bike is running lean, and if so, how can I tell that it's running lean? Thanks.

Re: overheating issue

Posted: Fri May 31, 2019 7:26 pm
by JimDirt
It is normal for it to glow , the exhaust usually gets around 1500 degrees when Idling , the bike itself will overheat if left running for more than a few minutes , because even though it has a water pump to circulate the coolant , it still needs air flowing thru the radiator to actually cool the system , so just sitting , everything will get hot......... With that said ...... Check your fuel screw , and see how many turns it is from lightly seated , so turn it clockwise till it lightly seats , counting the turns as you go , it should be no less than 1-3/4 turns out and no more than 2-1/2 turns out , if you need to turn it in less than 1-3/4 then you are too rich and need a smaller pilot , if you need to go more than 2-3/4 out then you are too lean and need to go to the next larger size pilot jet ......it should be in the highest idle , then back it off 1/4 turn , and it should still run with no popping/backfiring , and/or no bogging when snapping the throttle , it should idle the highest within those specs , then you are jetted fine ;)

Re: overheating issue

Posted: Mon Jul 08, 2019 2:34 am
by jackfrank
Hi all, hoping some one can help with an overheating problem I have with my CRF 450X 2010. I've had this bike quite a while and never had a single issue with it. On my last 2 rides the bike overheated and dumped a lot of coolant out of it. The first time was at the top of a difficult hill - enduro and the second time when i was doing a lot of waiting at idle riding with my daughter. I assumed after the second time i had a cooling system issue . After doing a bit of online research everyone who has a problem like this heads for jetting or exhaust changes, not one person even mentioned the cooling system ! I found this odd but it did get me thinking , I noticed after the last ride before the heating issue that i had damage to the header pipe where it bends around the engine. It must have coped a hit and it was slightly kinked directly after it leaves the engine . I'm not sure when i did this and did not notice a performance change. Maybe just a coincidence but it is the only thing different about the bike. The bike is completely stock, I love it the way it is! has anyone had this problem ? Can anyone help me ?
I have the same problem with my CRF. Just going to 3-5 miles the engine becomes so hot and the heat comes and touches to my feet. Don't make out what need to do?