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Can anyone tell me what the normal operating temp or warmup is for a Sportsman 450 (2017). After having a couple plugs foul up, I was told that the 450’s are notorious for this if you don’t let them warm up to operating temp before driving. Well I’ve had someone at the dealer tell me anywhere from 3 minutes to 10+, which sounds ridiculous. I keep the temp gauge display in view and it would be nice just to look at that and know when it’s ready. Some times I need to just jump on it to make a run on my property, so it’d be nice not to have to wait longer than necessary.
Thanks
 

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Sounds like a crock of BS to me. The EXACT temp don't matter. Start the machine and let it run 2 or 3 minutes while you get yourself ready to go... gloves, helmet, cargo, etc. and it will be fine. Then just make sure you ride long enough to get it fully heated before shutting off. Short cold stop and starts are what you need to avoid.
Looks like the OEM plug is a standard Autolite. Switching to a NGK Iridium plug would probably help too
 

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I tell you everyone I ride with lets their wheelers warm up. id say from 3-5min. ive always been one for warming up machines. its also important to not hammer the throttle out of the gate. taking it easy for the first mile or so gets a little heat in the belt which is good for it.
 

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agreed switch to the NGK iridium. my champions looked good after 2,500 miles but I pulled them due to a rich smell in my exhaust and the iridiums solved that issue. so even though my oem og champions showed no sign of a rich condition the NGKs were that much more efficient and no more gas smell complaints from my riding buds.
 

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Most engines foul the plugs during warm up when the air/fuel mix is richest - EFI engines do not require warm up for proper performance and it makes it easy to run a cold engine too hard - carburetor engines will not perform well until warmed up and it's the warming process that will foul a plug. With EFI, the fuel/air ratio is essentially the same for all air and engine temperatures - on the other hand, carburetors are lean with cold air entering the venturi and rich with warm air - that's what makes EFI attractive; the fuel/air ratio is electronically corrected for air and engine temperatures allowing the engine to run well at both extremes - a carburetor controlled engine needs the mixture enriched when the air temperature is low. Two methods of enriching the mixture is to choke off the air supply (less air = more fuel) and the bypass starter jet (enrichener). Choking of the air supply is basically self explanatory. The bypass starter jet is a bit more complicated, but serves the same purpose. In the bypass enrichener, a valve (plunger) is retracted opening an air passage that 'bypasses' the butterfly throttle plate. Opening of this passage allows a fuel rich mixture to enter the engine to aid cold starting - the opening of the bypass circuit provides for increased idle speed without the need to prop open the throttle as in choke systems. The idle speed of the bypass enrichener may be set by controlling the amount of air entering the engine by either the size of passage or an air jet screwed into the passage.

Plug fouling during start up is more prevalent with a choke, an occurrence with a bypass enrichener and almost non-existent with EFI. A fast idle is better for the engine than a low idle speed during warm up - a fast idle means higher oil pressure which in turn warms the oil faster by forcing it through small clearances.

As a rule, you should not use any more choke or enrichener than is necessary to keep a cold engine running and start riding as soon as it will perform sufficiently using just enough choke or enrichener to keep the engine running at a moderate speed.

All internal combustion engines should be run at moderate speed (about 3000 RPM) until it reaches (or is close to) normal operating temp. With a temp gauge this is about 150 degrees. Without a temp gauge, the engine or radiator should be hot enough that you don't want to touch it for more than a few seconds.

There are as many exceptions and variables as there is engine designs. Partly depends on type and viscosity of the oil used as well as the internal tolerances of the engine, fuel used, design of the ignition system and the spark plug used.

Note: all spark plugs start at the same temperature. The difference between a hot and cold plug is not the temperature it starts at, but the temperature it runs at when the engine is at normal operating temperature. The spark is not any hotter on a hot plug than it is on a cold plug. The spark is the same temp hot or cold, but an Iridium plug has a hotter spark than a standard plug by design.

Yeah - the guy who told you that was misinformed.
 

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"With EFI, the fuel/air ratio is essentially the same for all air and engine temperatures..."
You sure about that statement latebird?
I don't know all the details about how the ECU controls the fuel/air mix, injector opening and duration in conjunction with feedback from the TBAP and engine temp sensors on the EFI machines during warm up, but what I DO know is that when started up cold they smell rich, idle at a much higher rpm and will burn your eyes and nose when standing behind the machine until they get warmed up. Then, when they start getting up to operating temp, the idle settles down to normal and the raw fuel fumes dissipate.
 

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"With EFI, the fuel/air ratio is essentially the same for all air and engine temperatures..."
You sure about that statement latebird?
The ECU does it's best to maintain a 14-16:1 (theoretically ideal at 14.7 parts of air to 1 part of gasoline) air to fuel ratio for all air densities - it depends on the program installed in the ECU. The minimum AFR is around 6:1 and the maximum can go up to 20:1. An Air to Fuel Ratio of 16.5:1 is lean and 13.7:1 is rich and changes with engine RPM.

Ethanol requires about 9 parts of air to 1 part of fuel. Propane 15.67:1 and hydrogen 32:1

An engine can run with an excessively rich mixture easier and with less damage than an excessively lean mixture. The fuel map programmer may have the AFR at 13:1 when cold and 14:1 when hot, only the person who calculated the EFI map knows for sure, but the EFI tries to keep the ratio at around 14:1. When it's cold and the air is dense, the EFI has to adjust the timing on the injector to allow more fuel into the air stream. The ECU also adjusts the spark timing to increase engine speed for a fast idle - there is no servo motor or stepper solenoid on the throttle body to adjust the throttle position, so engine speed is controlled with timing.

I can orate most of the theory of EFI, but I can't troubleshoot or reprogram it worth a hoot.
 

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Gotcha latebird. Very informative.
Hope the OP don't mind I've hijacked his thread. He just hit on a subject that got my interest. (y)
 

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Gotcha latebird. Very informative.
Hope the OP don't mind I've hijacked his thread. He just hit on a subject that got my interest. (y)
Gotcha latebird. Very informative.
Hope the OP don't mind I've hijacked his thread. He just hit on a subject that got my interest. (y)
Don’t mind at all. All the info was very informative 👍. I will say that I know for a fact that it needs to be warmed to operating temp, just not necessarily 10 min. I have fouled up 3 plugs and I was told by several people that the EFIs are notorious for this if not warmed up.

I know I’m not an engine guy like Latebird, but it’s my understanding (self) that they inject a lot more fuel when they warm up; therefore accelerating hard prior to warm up will cause way to much to be injected. 🤷‍♂️ This last time I fouled it I’d been on and off it all day, but it sat for a couple hours before I put it away. Not thinking, I jumped right on it and took off to put it away. It was sluggish and I realized what I did. The next day it wouldn’t start. I changed the plug and it started righht up. The plug was completely fouled up.
 

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X2^^^^^^^^ switch plugs to NGK Iridium's. There's a chance that may be it.
 

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Well keep us posted only other thing I can say is assuming no codes have the ECU tuned by RVSPerformance. These machines are factory tuned to be compliant not efficient.
 

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V-power is just a glorified std. plug with a V grooved electrode - the iridium is a better design and much less prone to fouling
 
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