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I know that I've simply punched a hole or removed faulty car thermostats before, so why not just take the thermostat out of a bike if it fails? I was wondering if a professional motorcycle technician could explain the importance of a thermostat to me because motorcycles are usually operated in warm weather and have no heating/A.C. system.
 

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I know that I've simply punched a hole or removed faulty car thermostats before, so why not just take the thermostat out of a bike if it fails? I was wondering if a professional motorcycle technician could explain the importance of a thermostat to me because motorcycles are usually operated in warm weather and have no heating/A.C. system.
The thermostat is supposed to tell you where your engine operating temperature is at. If you don't care to know if your engine is going to overheat and shut down then by all my means disconnect it.


Also:

 

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I know that I've simply punched a hole or removed faulty car thermostats before, so why not just take the thermostat out of a bike if it fails? I was wondering if a professional motorcycle technician could explain the importance of a thermostat to me because motorcycles are usually operated in warm weather and have no heating/A.C. system.
Leaves me out.:angry
 

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When the coolant in the engine block gets to a certain temp, the thermostat opens up and the the hot coolant from the block, circulates into the radiator and the cooler coolant from the radiator circulates into the block and the thermostat closes off again.
The coolant absorbs heat from the block and the radiator absorbs heat from the coolant and the process starts all over again.
Without the thermostat and this process, the coolant will simply circulate full-time and will eventually get over heated, as it has no time to sit in the radiator and give up it's heat.
Replace it, it's cheap and essential.
I'm not a motorcycle tech, but I did stay at a Holiday Inn Express last night.

That, and I have a mild understanding of basic physics.
 

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But it whould be fine to run without a stat,
if you run seafoam and marvel mystery oil in your radiator and use 110 octane gas.
 

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The thermostat is supposed to tell you where your engine operating temperature is at. If you don't care to know if your engine is going to overheat and shut down then by all my means disconnect it.


Also:

Well, no... the thermostat regulates coolant flow to the radiator, doesn't tell you how hot or cold the bike is.

And you can go right ahead and take it out without any major issues - so long as you only ride when its 100 degrees out. Otherwise you are overcooling the motor. Engines are designed to run at a certain operating temp.
 

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Discussion Starter #7
But it whould be fine to run without a stat,
if you run seafoam and marvel mystery oil in your radiator and use 110 octane gas.
I am a fan of products such as engine ice but I'm not too sure what the seafoam is-Is it worth purchasing?....As for the 110 octane, I just ran a tank of 110 sunoco but I mixed it with 89 octane pump gas(1gal-110/3.5gal of 89). I didn't notice much of a power boost but the bike ran really smooth and was quiet. Do you think that the 110 is any benefit to a stock zx9 engine with a 12.2:1 compression ratio? By the way, good explanation on the coolant question-These bikes are a lot smaller than cars but heat can damage them a lot easier and air cooling is not as much of a help as I once believed.
 

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Without the thermostat and this process, the coolant will simply circulate full-time and will eventually get over heated, as it has no time to sit in the radiator and give up it's heat.
Nope. It over cools the coolant this way, not under cools. The thermostat doesn't open up for a second, let the coolant in, and then close so it can sit and chill in the shade for a minute and catch its breath.

It opens, the radiator cools the coolant flowing through it, and once the coolant coming from the motor is cool enough it closes again.
 

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I am a fan of products such as engine ice but I'm not too sure what the seafoam is-Is it worth purchasing?....As for the 110 octane, I just ran a tank of 110 sunoco but I mixed it with 89 octane pump gas(1gal-110/3.5gal of 89). I didn't notice much of a power boost but the bike ran really smooth and was quiet. Do you think that the 110 is any benefit to a stock zx9 engine with a 12.2:1 compression ratio? By the way, good explanation on the coolant question-These bikes are a lot smaller than cars but heat can damage them a lot easier and air cooling is not as much of a help as I once believed.
Higher octane gives you precisely zero power boost unless your engine is retarding the ignition automatically to compensate for lower octane fuel. (Do bikes even do that? I know some cars do) Which just means you are getting the proper amount of power, not a boost.

And no, you don't need no damn 110 octane in a bike that doesn't have any work done to the engine. The idea is to use the lowest octane that is safe for the engine, in most cases mid grade is more than enough and premium is just a waste of money. If you are actually shelling out the coin for 110, you are really wasting cash.

Chances are some 91 would work just fine if you actually noticed that the bike runs smoother and are not just imagining it.
 

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Well, no... the thermostat regulates coolant flow to the radiator, doesn't tell you how hot or cold the bike is.

And you can go right ahead and take it out without any major issues - so long as you only ride when its 100 degrees out. Otherwise you are overcooling the motor. Engines are designed to run at a certain operating temp.
Yes sorry, technically I'm wrong and Masta Squidge is right. I just meant that without the thermostat the bike can't tell you what the engine operating temperature is. Thanks for correcting me MS :cheers.

Damn, I should have spent the time to read the wiki page on thermostats before posting like the "professional motorcycle technicians". Oh wait, a "professional motorcycle technician" hasn't posted yet. :squint
 

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I don't see how splitting hairs over which way the coolant flows, is helpful to expressing the point that he shouldn't remove his thermostat.

And......
pull your thermostat out in mid summer and drive around in stop/go city traffic for 2 hrs and let me know how over-cooled it stays :thumbup.
 

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I remember that question from HS autoshop

The answer is pressure and temperature regulation. Like above, the engine was engineered for the expansion of its metal parts operating at ~160+ degrees (143+ on my 9Rs). However, if you take the thermostat out, according to the book, that without the thermostat's designed pressure bottleneck, the engine will actually overheat or simply run hotter.

I've never tested this idea, since I've always had thermostats in my vehicles and they don't overheat. :lol Not much point in aggravating the situation in my estimation and there are more than a few found in a quick Google search that say exactly that: thermostat out, overheating :headscratch :rant
 

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And......
pull your thermostat out in mid summer and drive around in stop/go city traffic for 2 hrs and let me know how over-cooled it stays :thumbup.
Its not going to overheat.

That was my point in the first place, pull it out in the summer - fine. If it is hot enough it basically stays open long enough to where it may as well not be there.

But on a cooler day, you actually are "overcooling" your engine.
 

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The answer is pressure and temperature regulation. Like above, the engine was engineered for the expansion of its metal parts operating at ~160+ degrees (143+ on my 9Rs). However, if you take the thermostat out, according to the book, that without the thermostat's designed pressure bottleneck, the engine will actually overheat or simply run hotter.

I've never tested this idea, since I've always had thermostats in my vehicles and they don't overheat. :lol Not much point in aggravating the situation in my estimation and there are more than a few found in a quick Google search that say exactly that: thermostat out, overheating :headscratch :rant
You know, that makes a little more sense too. Even when the thermostat is open it still restricts flow enough to keep the coolant circulating within the block. Without it, it might just bypass the return line to the motor (or wherever it goes form the housing) and flow from the pump to the radiator and back again without making it through the block.

I've been operating under the idea that its stuck open rather than removed....


At any rate, i am sure there are automotive thermostats that would be a direct drop in, as there is at least 2 bikes I have heard of that can use honda ones.
 

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I don't think it's gonna overheat either. But it will take a very long time to get warm and not run well until it's warm. I had a car that I ran without a thermostat for a while. It ran, and didn't overheat, but was very unhappy.
 

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I don't think it's gonna overheat either. But it will take a very long time to get warm and not run well until it's warm. I had a car that I ran without a thermostat for a while. It ran, and didn't overheat, but was very unhappy.
I drove my cavalier in the winter with a stuck thermostat.

In ran like crap and the temp gauge never even moved.
 

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Not true

Wow-youz guyz have a lot of good input on this question-Thanks for all of the good answers!!
We are no help and we pride ourselves in providing the least help ever! :evil
 

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Kawasaki tells me in some models the coolant temp is used for afr in a stock PCM. Won't tell me the models. If it didn't need one why would the manufacture have it? Do ya need headlights on a bike. No so take them out too I guess lol
 

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Yes, thermostats are completely useless and a vehicle will run absolutely NO different with/without one.
The engineers who came up with sticking a thermostat in the middle of a vehicle's liquid cooling system, were just sitting around, bored.....and were just trying to think up some random, extra shit to stick in a vehicle.

Air in your tires is another scam. Absolutely unnecessary.
Air suppliers are laughing all the way to the bank.
Same thing with brake fluid and a ton of other stuff.
 
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