Engine Temps

twricky · October 30th, 2012, 11:11 PM

Sorry guys, been lurking here for awhile but yet to participate. I have a FI 2009 Ninjette in Taiwan. My bike runs a bit hot in the summer and would like to have a better indication of temperature. Looking to get a digital Koso gauge to do this.

1. Where is the best place to measure temperature: coolant after thermostat, oil in engine pan, or at the cylinder head (spark plug base sensor)?

2. Are there differences in ideal running temperature, and maximum running temperature of our bikes depending on where you read the temperature?

3. What are the ideal running temperature, and maximum running temperatures?

Thanks!

Rick

Domagoj · October 31st, 2012, 06:57 AM

Hey hello.

This is an extract from service manual for FI ninjette. Might give you some insight:

Permanent type antifreeze is used as a coolant to protect the cooling systemfromrust and corrosion. When the engine starts, the water pump turns and the coolant circulates.
The thermostat is a wax pellet type which opens or closes with coolant temperature changes. The thermostat continuously changes its valve opening to keep the coolant temperature at the proper level.
When coolant temperature is less than 63.5 ∼ 66.5°C (146 ∼ 152°F), the thermostat closes so that the coolant flow is restricted through the air bleeder hole, causing the engine to warm up more quickly.
When coolant temperature is more than 63.5 ∼ 66.5°C (146 ∼ 152°F), the thermostat opens and the coolant flows.
When the coolant temperature goes up beyond 103°C (217°F), the radiator fan relay conducts to operate the radiator fan. The radiator fan draws air through the radiator core when there is not sufficient air flow such as at low speeds. This increases up the cooling action of the radiator. When the
coolant temperature is below 98°C (208°F), the fan relay opens and the radiator fan stops.
In this way, this system controls the engine temperature within narrow limits where the engine operates most efficiently even if the engine load varies.
The system is pressurized by the radiator cap to suppress boiling and the resultant air bubbles which can cause engine overheating. As the engine warms up, the coolant in the radiator and the water jacket expands. The excess coolant flows through the radiator cap and hose to the reserve tank
to be stored there temporarily. Conversely, as the engine cools down, the coolant in the radiator and the water jacket contracts, and the stored coolant flows back to the radiator from the reserve tank.
The radiator cap has two valves. One is a pressure valve which holds the pressure in the system when the engine is running. When the pressure exceeds 93 ∼ 123 kPa (0.95 ∼ 1.25 kgf/cm², 13 ∼ 18 psi), the pressure valve opens and releases the pressure to the reserve tank. As soon as pressure
escapes, the valve closes, and keeps the pressure at 93 ∼ 123 kPa (0.95 ∼ 1.25 kgf/cm², 13 ∼ 18 psi).
When the engine cools down, another small valve (vacuum valve) in the cap opens. As the coolant cools, the coolant contracts to form a vacuum in the system. The vacuum valve opens and allows the coolant from the reserve tank to enter the radiator.

flynjay · October 31st, 2012, 06:58 AM

Quote:

Originally Posted by twricky

Sorry guys, been lurking here for awhile but yet to participate. I have a FI 2009 Ninjette in Taiwan. My bike runs a bit hot in the summer and would like to have a better indication of temperature. Looking to get a digital Koso gauge to do this.

1. Where is the best place to measure temperature: coolant after thermostat, oil in engine pan, or at the cylinder head (spark plug base sensor)?

2. Are there differences in ideal running temperature, and maximum running temperature of our bikes depending on where you read the temperature?

3. What are the ideal running temperature, and maximum running temperatures?

Thanks!

Rick

Basically anything under the redline is good. Of course my '07 has a temp gauge so I have an idea to what it's doing. The temperature goes through the whole range depending on traffic, with it sitting just below the redline while in standstill traffic.

As long as your engine temp light is not coming on then you are fine.

Standard engine temps are 160-212 deg F, with 180 being somewhat optimal.

Motofool · October 31st, 2012, 07:21 AM

Quote:

Originally Posted by twricky

1. Where is the best place to measure temperature: coolant after thermostat, oil in engine pan, or at the cylinder head (spark plug base sensor)?

2. Are there differences in ideal running temperature, and maximum running temperature of our bikes depending on where you read the temperature?

3. What are the ideal running temperature, and maximum running temperatures?

Rick,

Welcome to the site !!

These measurements were made with an infrared thermometer (pistol type) at very close range:

http://faq.ninja250.org/wiki/File:841135.jpg

http://faq.ninja250.org/wiki/Cooling_system

http://www.professionalequipment.com...d-thermometer/

twricky · October 31st, 2012, 05:58 PM

Thanks all for the excellent references! I'm a bit more comfortable in understanding the cooling system and temperatures now.

With an aftermarket digital temp gauge, and having to choose one source for reading temp, what would the best decision be: coolant; oil; or cylinder head?

I'm thinking cylinder head (the source of the heat), but perhaps I can run two sensors (cylinder head and coolant) and toggle between them with a switch.

I believe the Koso RX2 gauge has two readings, coolant, and oil. However I like the simplicity of the Koso RX2N-R which only has one temp reading.

Thanks again,

Rick

October 30th, 2012, 11:11 PM	#1
twricky ninjette.org newbie Name: Rick Location: Taiwan Join Date: Feb 2011 Motorcycle(s): ninja 250 Posts: 2	Engine Temps Sorry guys, been lurking here for awhile but yet to participate. I have a FI 2009 Ninjette in Taiwan. My bike runs a bit hot in the summer and would like to have a better indication of temperature. Looking to get a digital Koso gauge to do this. 1. Where is the best place to measure temperature: coolant after thermostat, oil in engine pan, or at the cylinder head (spark plug base sensor)? 2. Are there differences in ideal running temperature, and maximum running temperature of our bikes depending on where you read the temperature? 3. What are the ideal running temperature, and maximum running temperatures? Thanks! Rick

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
For all of us looking out the door at single digit temps	allanoue	Videos	7	January 16th, 2014 07:03 PM
Bike is running good in colder temps.	subxero	General Motorcycling Discussion	6	November 11th, 2013 05:09 PM
Rotella t6 temps/ interval? oil change	cessus	1986 - 2007 Ninja 250R Tech Talk	12	April 8th, 2013 06:34 PM
Day temps. in 50's	coondog	Ride Reports	4	March 7th, 2012 10:02 AM
Winter Engine Temps	EtienneDP	2008 - 2012 Ninja 250R Tech Talk	4	June 8th, 2011 07:21 AM

October 31st, 2012, 06:57 AM	#2
Domagoj ninjette.org guru Name: Domagoj Location: Rijeka, Croatia Join Date: Aug 2010 Motorcycle(s): Ninja 250r 2009 Posts: 396	Hey hello. This is an extract from service manual for FI ninjette. Might give you some insight: Permanent type antifreeze is used as a coolant to protect the cooling systemfromrust and corrosion. When the engine starts, the water pump turns and the coolant circulates. The thermostat is a wax pellet type which opens or closes with coolant temperature changes. The thermostat continuously changes its valve opening to keep the coolant temperature at the proper level. When coolant temperature is less than 63.5 ∼ 66.5°C (146 ∼ 152°F), the thermostat closes so that the coolant flow is restricted through the air bleeder hole, causing the engine to warm up more quickly. When coolant temperature is more than 63.5 ∼ 66.5°C (146 ∼ 152°F), the thermostat opens and the coolant flows. When the coolant temperature goes up beyond 103°C (217°F), the radiator fan relay conducts to operate the radiator fan. The radiator fan draws air through the radiator core when there is not sufficient air flow such as at low speeds. This increases up the cooling action of the radiator. When the coolant temperature is below 98°C (208°F), the fan relay opens and the radiator fan stops. In this way, this system controls the engine temperature within narrow limits where the engine operates most efficiently even if the engine load varies. The system is pressurized by the radiator cap to suppress boiling and the resultant air bubbles which can cause engine overheating. As the engine warms up, the coolant in the radiator and the water jacket expands. The excess coolant flows through the radiator cap and hose to the reserve tank to be stored there temporarily. Conversely, as the engine cools down, the coolant in the radiator and the water jacket contracts, and the stored coolant flows back to the radiator from the reserve tank. The radiator cap has two valves. One is a pressure valve which holds the pressure in the system when the engine is running. When the pressure exceeds 93 ∼ 123 kPa (0.95 ∼ 1.25 kgf/cm², 13 ∼ 18 psi), the pressure valve opens and releases the pressure to the reserve tank. As soon as pressure escapes, the valve closes, and keeps the pressure at 93 ∼ 123 kPa (0.95 ∼ 1.25 kgf/cm², 13 ∼ 18 psi). When the engine cools down, another small valve (vacuum valve) in the cap opens. As the coolant cools, the coolant contracts to form a vacuum in the system. The vacuum valve opens and allows the coolant from the reserve tank to enter the radiator.

October 31st, 2012, 05:58 PM	#5
twricky ninjette.org newbie Name: Rick Location: Taiwan Join Date: Feb 2011 Motorcycle(s): ninja 250 Posts: 2	Thanks all for the excellent references! I'm a bit more comfortable in understanding the cooling system and temperatures now. With an aftermarket digital temp gauge, and having to choose one source for reading temp, what would the best decision be: coolant; oil; or cylinder head? I'm thinking cylinder head (the source of the heat), but perhaps I can run two sensors (cylinder head and coolant) and toggle between them with a switch. I believe the Koso RX2 gauge has two readings, coolant, and oil. However I like the simplicity of the Koso RX2N-R which only has one temp reading. Thanks again, Rick