300exc overheating

[Ktmboy]

Its got nothing to do with all of the above. The 300exc, up to 2009 are prone to getting hot. Why do you think they made adjustments to the radiator cap for the last version.

Yes, I take Dangers view that the enduro scenario is relevant. But when you are man handling the freakin thing for 30 minutes(not just a simple hill climb)in first gear through jungle then it makes no difference if its summer or winter. If you are doing the wires then I'd be doing surgery.
Removing the thermostat increases the volume of coolant through the radiator as there is a restriction where the thermostat housing is.
Simple trail riding or enduro racing then a bit of coolant spew is ok.

[4stroke]

Thermostat sits inline where your hoses join under the fuel tank.

I've heard the big-banger katoom is a bit more prone to boil ups. I've had my 200 pretty hot when running hard in deep sand though, & have thought about removing the thermostat for summer. Advantage as I understand is improved flow rate at this point. Never eyeballed it but certainly must be something to it if Birchy does it. I prefer the idea of my bike getting up to operating temp faster but might try removing it for summer.

Would pay to check your hoses for kinks that might interfere with flow as well. The hose coming off the head on mine used to be a bit too long and this caused a pronounced flat spot in it at the tightest bend.

When I first got mine, it lost a little coolant every ride so I ordered a new rad cap. On close look I noticed cap wasn't sitting square & flat. Rad filler neck had taken a knock at some point and lip was a bit distorted. Ali on these rads is very soft (was easy to straighten out) & no lost coolant since.

Barty made a good point about keeping the fins/cores as clean as possible. You can't hit 'em with pressure washer so they may not be as clean as they appear at a glance. When I did my top end I soaked my rads (twice) overnight in buckets of hot water laundry detergent & nappisan. Gave 'em a good swish back & forth in water. A surprising amount of extra crap came off them. Even a thin layer of this probably not good for heat dissapation. I even went to trouble of straightening out the bent fins to make 'em pretty again, also easier to wash & less likely to hold dirt.

Re what Danger noted about water being the superior part of your coolant recipe. I've heard of that before. Apparently water 'sits better' (for want of a better term) against hot metal & enables better heat transfer? I use that 'Engine Ice' brand stuff and was going to try a 25/75 ratio last summer but it says on pack to leave it 50/50, so I didn't try it. Can't really see the harm though. We don't really need the antifreeze factor much here & you'd think 25% ratio of whatever anti-corrosion agent is in there should be enough if using distilled water? Be interested to know more about this. You don't worry about corrosion 4 stroke?

water wetter has corosion inhibitor in it and also an anti-freeze agent, down to about 5 degrees below tho. but as for anti-boil this stuff is incredible, pure water has a better cooling efficiantcy then anti-freeze\water mix

[flyingcr250]

water wetter has corosion inhibitor in it and also an anti-freeze agent, down to about 5 degrees below tho. but as for anti-boil this stuff is incredible, pure water has a better cooling efficiantcy then anti-freeze\water mix

were do you get water wetter from??

[camchain]

Its got nothing to do with all of the above. The 300exc, up to 2009 are prone to getting hot.

Woops. Mainly first line of my post was really meant for flyingCR. Rest of it way too general for this thread I s'pose. Point taken, didn't mean to confuse the issue.

[4stroke]

were do you get water wetter from??

BNT i where i got mine from, make sure you get the pinky coloured stuff not the purple stuff--thats for diesels and trucks etc.

here i found this, should answer some q's
http://www.expotv.com/videos/reviews...rwetter/173095

[B0000M]

BNT i where i got mine from, make sure you get the pinky coloured stuff not the purple stuff--thats for diesels and trucks etc.

here i found this, should answer some q's
http://www.expotv.com/videos/reviews...rwetter/173095

i run the diesel stuff in mine.

apparently the diesel stuff is better suited as diesels tend to run hotter- much like our bikes

added bonus too is the bottle is bigger

[4stroke]

good point, hadent actually thought bout it like that.

[IIIRII]

Do a search on tardme , I spotted 1 litre of coolant with very high boiling point for about $40 specifically for bikes....
Under bikes / parts , I think ....
Dont have tardme at work sorry or i'd post the link.

[barty5]

Do a search on tardme , I spotted 1 litre of coolant with very high boiling point for about $40 specifically for bikes....
Under bikes / parts , I think ....
Dont have tardme at work sorry or i'd post the link.

http://www.trademe.co.nz/Trade-Me-Mo...-232780828.htm


added it for yah

[dafydd roberts]

I run a temp gauge on my bike I got a little stuck the other day, was registering 135C for about 30min on the clock still wasn’t boiling. I just run a standard antifreeze/summer coolant 50/50 from super cheap.