Radiator Thermosat
- Thread starter 2stroke
- Start date
Automotive engines used 160* thermostats for many years. It was common to install a 180* thermostat in the winter to increase heat output from the heater.
Using increased engine temperature became important only for pollution control issues. Higher temperatures altered the formation of oxides and other harmful substances and helped the pollution control system perform better.
As long as an engine is warm enough that the oil viscosity allows proper oil flow, the engine will be fine. A 2T can operate successfully at lower temperatures than a 4T.
Using increased engine temperature became important only for pollution control issues. Higher temperatures altered the formation of oxides and other harmful substances and helped the pollution control system perform better.
As long as an engine is warm enough that the oil viscosity allows proper oil flow, the engine will be fine. A 2T can operate successfully at lower temperatures than a 4T.
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I'm still missing something. I have a clean carb (I just did it last weekend, and I am thorough), I have fresh gas, no ethanol, yet my bike will not run correctly until about 140. Of hundreds of engines of all kinds I've come across in my life, they all act in a similar matter
I don't think oil plays much a part of cars engine temperature. You can always use thinner oil. Back in the day of 160 thermostats, leaded gas, and carburetors, cars were lucky to make it 100 thousand miles, and required constant maintenance. Plus you had 10w oil, 20w oil, etc. With a 5w-30, you can cover a much larger temperature range. Now with 195 thermostats, and fuel injection, I have yet to see an engine honestly wear out. People blow them up, sure, but its always by abuse.
I'm not sure why this turned into a thread about how 2 strokes run ice cold. The fact is engineers designed the engine to run at a certain temperature, and I guarantee it isn't 120F. It has little to do with oil, and everything to do with tolerances, especially the piston and cylinder. I will lay money you do more damage running an engine hard at 120F than at 240F.
So with that, I will no longer respond to this thread unless its about thermostat housings. I'm simply too boneheaded to listen to more.
I don't think oil plays much a part of cars engine temperature. You can always use thinner oil. Back in the day of 160 thermostats, leaded gas, and carburetors, cars were lucky to make it 100 thousand miles, and required constant maintenance. Plus you had 10w oil, 20w oil, etc. With a 5w-30, you can cover a much larger temperature range. Now with 195 thermostats, and fuel injection, I have yet to see an engine honestly wear out. People blow them up, sure, but its always by abuse.
I'm not sure why this turned into a thread about how 2 strokes run ice cold. The fact is engineers designed the engine to run at a certain temperature, and I guarantee it isn't 120F. It has little to do with oil, and everything to do with tolerances, especially the piston and cylinder. I will lay money you do more damage running an engine hard at 120F than at 240F.
So with that, I will no longer respond to this thread unless its about thermostat housings. I'm simply too boneheaded to listen to more.
I have a 2011 EC 300 with the original factory thermostat. I have a trail tech with the red temp warning light set for 200 degrees F. My bike seems to run in the 160 to 180 range. It only gets to 200 degrees if I'm stuck in some dense tight grown over single track at a crawling speed, but it never has boiled over.
I have some buddies that ride pumpkins and they boil over constantly. Maybe the heavier sandcast engine cases of the GG act as a heat sink?
I have some buddies that ride pumpkins and they boil over constantly. Maybe the heavier sandcast engine cases of the GG act as a heat sink?
So the 2011 I saw with a thermostat was a factory add on, I just figured someone stole it from a KTM. Not sure why KTM would be more prone to overheating. Maybe you are mistaking boiling for simply spitting coolant? Good coolant shouldn't boil to 260+ depending on the radiator cap.
swazi_matt
Active member
I am convinced the ktm boiling issues are a result of their frame configuration. Their fuel tank just about blocks off the radiators whereas the GG frame means that the fuel tank sits between the radiators allowing much better air flow through the radiators.
Since i fitted a fan the bike will boil much quicker than without the fan purely from the restriction caused by the fan and the cowling (obviously this is if i forget to turn the fan on - with the fan on it never boils ... generally stalls on the next downhill because i forgot to turn it off!!)
Yes I did, I was asking what the best method was. A thermo-bob has a bypass to keep coolant re-circulating while the thermostat was closed, where the stock gasgas thermostat simply blocks one line until its open.
Best post ever .....
Here's my thoughts. The thermostat is just one more thing to go wrong. I think it came from a Euro emissions requirement (maybe not) and my gasser is the first bike I've ever owned to have one. I believe that when I melted down my engine, the thermostat was possibly at fault. I removed it and didn't notice any difference in how the bike ran. (After the repair obviously) In fact, it boiled over on me in exactly the same spot on the same trail, both before and after the t-stat. If the bike runs cooler without it, then great. I happy for the extra overhead.
barossi73
Gold Level Site Supporter
An engine with thermostat removed may or may not run cooler,depending on wether the full open stat is still having a restricting effect on max flow.
however with thermostat removed it will certainly take longer to warm up,esp in colder weather as right from start cooling circuits are full open.in fact in very cold weather it may not reach proper operating temp at all.
Changing the thermostat temp will also change the rate that an engine can warm up...its not just about the upper limit,but managing the operating temp through the whole temp range
however with thermostat removed it will certainly take longer to warm up,esp in colder weather as right from start cooling circuits are full open.in fact in very cold weather it may not reach proper operating temp at all.
Changing the thermostat temp will also change the rate that an engine can warm up...its not just about the upper limit,but managing the operating temp through the whole temp range
Correct. The thermostat bore is usually adequate for full flow in a dirtbike. The point in all of this is that if you want accurately regulated engine temperature, you need to put a thermostat on both sides. That will force the engine to reach operating temperature regardless of how the engine is being worked or not worked.
My engine will not get up to temp, that is why I started this thread. A thermostat won't affect the maximum temperature at all, only the minimum, and the engine warms up quicker.
I did not consider putting a thermostat on both radiators, I assumed one would have a good enough effect. All I want is to keep temperatures about 160-200f. My engine will live longer, and jetting will be consistent. Carburetors are bad enough as it is.
I did not consider putting a thermostat on both radiators, I assumed one would have a good enough effect. All I want is to keep temperatures about 160-200f. My engine will live longer, and jetting will be consistent. Carburetors are bad enough as it is.
barossi73
Gold Level Site Supporter
Personally i would leave it be(bigger safety margin) but you seem determined to try this,so before you get too far,why not blank off part of or all of 1 rad with cardboard temporarily.this should lift eng temp and allow you to be sure its not going to run like a bag of shit after you raise the operating temp.also higher eng temp will increase pressure in cooling circuit so rad cap will prob need uprating
That's a good idea, blocking off a radiator should give me a good idea how fast it will warm up.
Even if I decide I don't like a thermostat, its as simple as replacing a hose, and all of them could stand to be replaced anyway.
Raising the temperature up will certainly change how the bike runs, but I am going to start over with jetting, with a different carb and pipe anyway.
A higher pressure radiator cap is not a bad idea, mine is only 1.2 bar. I just started to get some coolant in my catch bottle when I got up to about 170F.
Even if I decide I don't like a thermostat, its as simple as replacing a hose, and all of them could stand to be replaced anyway.
Raising the temperature up will certainly change how the bike runs, but I am going to start over with jetting, with a different carb and pipe anyway.
A higher pressure radiator cap is not a bad idea, mine is only 1.2 bar. I just started to get some coolant in my catch bottle when I got up to about 170F.
