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Discussion Starter #1
There were some conversations on the Forum regarding how the bike might react to high ambient temperatures. The bike felt fine during today's 102F ride. Performance wise, it seemed to have that kinda cool increasing throttle sound when you're actually holding the throttle at a steady position--reminded me of my old Z1 bracket bike after I put in a big cam. The rad'r fan, heretofore not operating, came on when sitting at a longer traffic light. BTW, if the bike's on the lean side, it should like hot weather, right? (You have to richen up when its cooler, yes?). Anyway, from a rider/comfort perspective, I was pleased the bike didn't seem to have any undue hot spots. :)
 

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In general a lean mix will run hotter, more complete burn in the chamber; and a rich mix will run cooler, burn is incomplete and continues into the headers which have more exposed surface area and can shed heat more efficiently.

Of course, this depends on what the reference point for lean vs rich is. If you're already very lean, leaning just reduces the amount of fuel to burn, less heat overall produced; and riching just increases the amount burned, more heat overall. Peak efficiency though will be somewhere in the range where leaner is hotter and richer is cooler. Which is a little ambiguous, since you reach a point where richer is just flooding.

Unfortunately, this bike having a cat means you can't really use an exhaust tester to tune fueling as finely, ideally you get a complete reaction with high CO2:CO ratio by the exhaust opening. Though you could still get it pretty close if you tap the headers, if I recall correctly you want <1% residual hydrocarbon at 1 inch past the block.

With regard to ambient temperature, depending on how extreme a temperature difference, cool air is denser and you'd want slightly richer, but unless you demand extreme performance, you can trust the ECU to manage this.
 

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Discussion Starter #3 (Edited)
USSENTERNCC1701E, Thanks for the insight. I believe what you are describing must be the working mechanism of bikes like older FJR1300s that install a Power Commander to richen bike in effort to have it run cooler here in the desert. They achieve a cooler running bike, but then the mileage takes a big hit, like dropping from low 40s mpg to low 30s mpg. My old (stock) '84 Yammy FJ1100 ran so hot it was uncomfortable at anything approaching 100. Thankfully, the Sazook didn't really feel all that hot, which is great as maximum summer temperatures of 115 to 118 F are normal around here (Phoenix).
 

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Human beings are very sensitive to temperatures. We get cold when its 40, and 105 is hot. We have feelings, and a machine does not.

Engines, running at 180+ really dont care. Even the old air cooled motors were no problem.

Notice your temp gauge. Its not as if it runs 40 degrees cooler when its only 35 degrees outside.

Once it hits operating temperature, it will be pretty much identical to a 105 degree day.

As far as fuel needs, spark, etc. Back in the old days , we had carburetors and jets with no way to compensate. With the exception of highly tuned dirt bikes, you never changed jetting for a hot day or cold day.

I've never understood why, but often times when people feel heat on their skin, it automatically translates over to the motorcycle feeling heat. Whats even worse are those who will install a manual fan switch to "turn on" the fan when they feel like they should vs the thermostatically controlled switch?

The difference between 20 degrees and 100 is a big deal for a human, not much for a machine.

Running an engine too cool is a bad deal, too, but they never worry about that.
 

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BTW, if the bike's on the lean side, it should like hot weather, right? (You have to richen up when its cooler, yes?)
See this page for some info about cold-start enrichment: Cold Startup Enrichment / EFIDynoTuning

That aside, our GSX-S ECM has an intake air temperature sensor that compensates the mixture. Ideally our bikes will run at the same AFR in any environment. Which means (in stock form) it will always be a bit lean.
 

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Discussion Starter #6
RC and Jefro, Thanks for input. I gather the bike could care about local temp. But, I was worried about it being or running so hot you wouldn't want to ride it in the heat of summer, which is practically half the year here it's over 100F (39-40C). Two gals that run a local BMW rider's club didn't wear full gear (ie, pants) until they got the K1200RS (flying brick of late 90s) because the exhaust heat exiting on their left ankles was so hot that it would burn them. And my old r1100s was ok to ride comfort-wise but was even more lethargic in the heat, or start pinging when passing in top gear. So I don't see those as issues with this bike. :)
 

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bikes do not like hot weather and idling. You need to get up to speed to turn the water pump and the cooling system. For hotter weather I like to run water-wetter. Also, distilled water will help keep the temps down. Where I live (central CA) we can see temps of 110+ in the summer.
 

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Discussion Starter #8
Slothman, There we go. I commuted on my old beemer (no I'm not gay--I saw your other posting Ha) all summer and temps would go to 117-119 :(. Anyway, its my first water pumper, so what is water-wetter? BTW, you know the sound an all electric Prius , Nissan Leaf, Zero S etc makes.....iiiimmmmmmmmmmmggggggggaaaaaaayyyyyyyyyyy.
 

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bikes do not like hot weather and idling. You need to get up to speed to turn the water pump and the cooling system. For hotter weather I like to run water-wetter. Also, distilled water will help keep the temps down. Where I live (central CA) we can see temps of 110+ in the summer.

You are welcome to run whatever you choose, but distilled water is a poor choice in a cooling system.

Water likes being in the state it was in before the distillation process. It likes holding minerals and total dissolved solids.

When those parts are removed from water, through the distillation process, the water will find the solids and take them from the metal its exposed to...your engine.

The water you want is filtered water, held at a PH level of @7. The Di water is horrible, and distilled not much better with regards to erosion and /or corrosion.

Straight water is the best at temperature exchange, but there is nothing magical about distilled water.
 

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You are welcome to run whatever you choose, but distilled water is a poor choice in a cooling system.

Water likes being in the state it was in before the distillation process. It likes holding minerals and total dissolved solids.

When those parts are removed from water, through the distillation process, the water will find the solids and take them from the metal its exposed to...your engine.

The water you want is filtered water, held at a PH level of @7. The Di water is horrible, and distilled not much better with regards to erosion and /or corrosion.

Straight water is the best at temperature exchange, but there is nothing magical about distilled water.
I highly disagree. You don't want "regular" water in the system....it contains too many minerals. I have been around engines and racers all my life....everyone recommends distilled water mixed with coolant. For hotter weather, 75% water and 25% coolant is a good mix. We don't need the coolant as bad because we don't see freezing temps. The distilled water will keep the engine cooler. Also, water wetter is a great product. I have seen it drop temps in multiple motors. Just my 02 ....
 
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