YZ450 Power Drop when Hot

TheGetFresh
I have a 2021 YZ450 and I love it overall. One issue I’ve been having is with power drop when the bike gets really hot. Temps have been in the 90s the past few weeks and the bike isn’t overheating or spewing coolant, but the pipe and the fuel get pretty toasty. It suffers pretty bad in desert sand.

I know race gas will alleviate the issue, but I’d prefer not to spend $15 buck+ a gallon all summer. Anybody know any other fixes for this? Different coolant? Maps? I’m open to pretty much anything.
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J-Mill
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J-Mill 6/11/2021 10:59pm
6/11/2021 10:59pm Edited Date/Time 6/11/2021 11:00pm
Not sure race gas will help this as I understand some race fuels have a lower boiling point than pump gas... If you really think heat is the issue, I’d put some heat shield material under the tank and put some Engine Ice coolant in it. If that doesn’t help I’m not so sure heat is the problem.
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TheGetFresh 6/11/2021 11:06pm
6/11/2021 11:06pm
J-Mill wrote:
Not sure race gas will help this as I understand some race fuels have a lower boiling point than pump gas... If you really think heat...
Not sure race gas will help this as I understand some race fuels have a lower boiling point than pump gas... If you really think heat is the issue, I’d put some heat shield material under the tank and put some Engine Ice coolant in it. If that doesn’t help I’m not so sure heat is the problem.
That sounds like a good start. I’ll try some engine ice and I’ve got the foil tape laying around.

As for the race gas, I haven’t tried it but I’m running 91 octane with 10% ethanol now (I’m at high altitude so nobody sells anything higher). When the bike is hot the throttle response just feels limp, so I’m thinking race gas would keep it crisp.
Yeti831
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Yeti831 6/12/2021 9:21am
6/12/2021 9:21am Edited Date/Time 6/12/2021 9:24am
Nah, it honestly sounds like hot fuel. Race doesn’t make an engine cooler. And like other guy said SOME race gas (mainly the unleaded stuff) Does boil slightly lower then pump. So if anything you’ll just exaggerate issue further.

Does it bog or when get on it will it “miss” in a spot power wise?

Do what first response said. Engine ice is indeed great, but I’ve made heat reflective tape a mandatory addition to any bike I get since 2016.
TheGetFresh 6/12/2021 1:02pm
6/12/2021 1:02pm
It’s not a hard bog, but it feels weak throughout. No kink in the power delivery, just a disconnect from throttle to rear wheel. Last ride it was bad enough that Got off in the middle of a desert loop to check the drive chain and then coolant after the bike cooled enough. Both we’re exactly where they should have been.

I’m thinking you guys are right about the fuel temps. I ride at about 5-6k ft. altitude in about 95 degree heat. Water boils about 5% lower temp up here so I imagine gas’ percentage decrease could be even worse given the lower density. I’ve never boiled fuel before, so I’m not sure what to feel for when a bike is overheating the gas.

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Factor E
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Factor E 6/12/2021 8:00pm
6/12/2021 8:00pm
TRY RUNNING HALF AV GAS AN PUMP GAS

COOLANT - ENGINE ICE OR LIQUID PERFORMACE
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