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This has came to mind as bike bandit screwed me over time wise before a trackday. This is for my 05 6R. I'm pretty sure I have a fault thermostat but can't get one in time before my track day is it possible to run without one or will there be a gap or can I force it open and lock it?

Also what is the point of a thermostat in a bike. I understand want there for but other than the warm up from a cold start or riding in cold temps it really seems almost pointless. Am I crazy?
 

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no ! your not crazy just misinformed .

The thermostat is very important , It stays closed so that the engine gets up to temp quickly and once up to temp opens to allow the radiator to cool . you may think that removing it may only affect the warm up ,but by slowing down the flow it also keep the engine cool by allowing the coolant to stay in the radiator long enough to cool before flowing back into the engine .
The engine is designed to operate at a certain temp . The pistons are actually oval and once up to temp become round . So too hot or too cold the engine with either burn oil /low compression or too tight and damage internals .
You may get away by removing the thermostat and placing a restricted plate . A small round disc with a smaller hole in center . I would guess around 3/4 of an inch , which would slow down flow and allow some cooling .

by the way , you can go to you local autopart and get any automotive thermostat that fits in the hole and even trim to fit . Most ever engine has a thermostat of 195 like the one in your bike .
hope that helps .
 

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I stopped running thermostats in my CARBED bikes years ago.....BUT for a FI bike , the systems uses the consistent temps to run the system.....

For a pinch, I'd cut the spring out and the plunger....untill the new one you ordered arrives.
 

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no ! your not crazy just misinformed .

The thermostat is very important , It stays closed so that the engine gets up to temp quickly and once up to temp opens to allow the radiator to cool . you may think that removing it may only affect the warm up ,but by slowing down the flow it also keep the engine cool by allowing the coolant to stay in the radiator long enough to cool before flowing back into the engine .
The engine is designed to operate at a certain temp . The pistons are actually oval and once up to temp become round . So too hot or too cold the engine with either burn oil /low compression or too tight and damage internals .
You may get away by removing the thermostat and placing a restricted plate . A small round disc with a smaller hole in center . I would guess around 3/4 of an inch , which would slow down flow and allow some cooling .

by the way , you can go to you local autopart and get any automotive thermostat that fits in the hole and even trim to fit . Most ever engine has a thermostat of 195 like the one in your bike .
hope that helps .
Wow talk about misinformation!!!

The whole purpose of the thermostat is to regulate the engine temp and keed it within a specified operating temperature range. If you remove it the engine will run too cool. It will take a long time to warm up and will not stay in the ideal temp range.
YOUR PISTONS ARE NOT OVAL!:rolleyes: however they do expand along with all the other parts that are designed with tolerances that account for them being at certain temps. On some motors the ecu runs a completely diff map and switches from open to closed loop mode depending on the temp, not sure about the zx10r.
 

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For a pinch, I'd cut the spring out and the plunger....untill the new one you ordered arrives.
This.

I'd also take it out and test it in a pot on the stove in water. Is it sticking closed? You may be able to get it to work better just by placing it in water on the stove and watching it try to open and close and helping it free up a bit. But for 1 trackday, I'd try modifying it slightly and leaving it in the system.
 

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I have been told running without a thermostat over a long period of time. Can cause carbon build up inside of the engine due to not reaching the proper operating temp.
 

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Wow talk about misinformation!!!

The whole purpose of the thermostat is to regulate the engine temp and keed it within a specified operating temperature range. If you remove it the engine will run too cool. It will take a long time to warm up and will not stay in the ideal temp range.
YOUR PISTONS ARE NOT OVAL!:rolleyes: however they do expand along with all the other parts that are designed with tolerances that account for them being at certain temps. On some motors the ecu runs a completely diff map and switches from open to closed loop mode depending on the temp, not sure about the zx10r.
I am a MASTER ASE MASTER MECHANIC , maybe i did not make my explanation clear , i was trying to explain that is is very important to have a thermostat in place and how to get away without it temporarily .

and for your information SIR > pistons are oval when cold and designed to expand to round when at temperature .

Question ...where were your education in Motor mechanics ?
 

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no ! your not crazy just misinformed .

The thermostat is very important , It stays closed so that the engine gets up to temp quickly and once up to temp opens to allow the radiator to cool . you may think that removing it may only affect the warm up ,but by slowing down the flow it also keep the engine cool by allowing the coolant to stay in the radiator long enough to cool before flowing back into the engine .
The engine is designed to operate at a certain temp . The pistons are actually oval and once up to temp become round . So too hot or too cold the engine with either burn oil /low compression or too tight and damage internals .
You may get away by removing the thermostat and placing a restricted plate . A small round disc with a smaller hole in center . I would guess around 3/4 of an inch , which would slow down flow and allow some cooling .

by the way , you can go to you local autopart and get any automotive thermostat that fits in the hole and even trim to fit . Most ever engine has a thermostat of 195 like the one in your bike .
hope that helps .
This guy is right. Almost everything in the engine us engineered to be optimal inside of this temp range, including fuel metering and air flow. And yes, the pistons are ground to a slightly oval shape to compensate for the extra metal expansion around the gudgeon pin. Running at below normal operating temp can cause premature wear on the front and rear of the pistons.
 

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whether he is right or wrong, the thermostat sure as shit is not a 195* rated one though. The damn thing opens at 140*, check the service manual. Page 4-16 or on PDF its around page 220. Go let your bike warm up from being cold. watch the temp drop once the gauge reads 139-141*F. All of a sudden it stops rising, drops, and then rises. these bikes have an undersized radiator for just sitting around and not moving. The thermostat is to help restrict the coolant flow to let it warm up so you can get to operating temperature properly. once the bike is on and up to operating temperature and you start riding it though, the thing rarely gets close to closing because its usually just not cold enough outside. Then it will adjust to keep the bike at operating temperature. The radiators on these bikes do not have enough coolant/cooling capacity for the thermostat to really do much in terms of keeping temperatures down. What it does do is keep them up if you get into a situation where the bike wants to keep cooling below that

Dont just remove the thing unless you intend to replace very very soon. (Like if you needed to ride the bike to get the part, bring it home and change it.)
 

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I am rarely ever wrong . I am one of the top mechanic in the country . Thermostats do not suddenly open at a certain temp but gradually open until fully opened at rated temp .
 

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I am rarely ever wrong . I am one of the top mechanic in the country . Thermostats do not suddenly open at a certain temp but gradually open until fully opened at rated temp .
:+1:clearly & correct.

Thermostats will start to open at 140F for sure. but not sure when it has fully opened.because the radiator fan start at 203F and stop at 194F,I doubt it's too late that thermostats just fully opened at 195F.

Normally 20-30F increased above the start temp seem like reasonable for me.
 

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hello guys i tried to remove my thermostat my bike it runs cooler then ever but its not a good idea to remove it because when the air flow is not hitting the radiator very well , the temp will clamp up, so the over heating will occur when you are in traffic or tunnel or highway when there is a vehicle in front of you blocking the air flow , so its a fucked up idea to remove the thermostat :)
 

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I'd love to see the machine that makes oval pistons.......
 

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Yeah, sure he did....... There is a difference from top and bottom, but oval, no.
 

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I kind of understand the logic....

But on topic, racers can benefit from the added flow from the restriction loss, but street worth its more so the fi system can do its job better
 
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