Engine shuts down in hot weather

Hello everyone!
Need suggestions to fix my bike.
Case:
in hot weather about 85F engine drops RPM in several steps and shuts down. If I wait for about 20 minutes it starts normally without any error messages.
Some additional observations: last time this happened while simple run for about 20 minutes on 60 mph (3000 rpm). I suggest there was good air stream and I didn't feel overheat with my legs. But it seemed to me the bike slightly changed reaction on throttle before shutting down - like riding through gel.
I've experienced this step by step shuting down last year when the fan fuse burned and bike starts to overheat in heavy traffic. But this time it happens even on free roads.

I've checked:
- rear head fan and temp sensor. Heat up engine on 1000 RPM monitoring temperature with ECMspy. Fan starts normally at about 220 degrees (C), didn't spot any glitches with engine temp readings. Looks everything works fine.
- O2 sensor. Switched it of physically and in ECMspy assuming that it can get wrong measurements and ECM lowering fuel amount. No changes.
- cleaned up external air temp sensor - no changes.

For now i've got only one idea - fuel is heated up and fuel pump cannot provide enough performance. BTW the bike has 60 000 km already and it's 2005 year make. I don't know was fuel pump ever changed or not.

I would be very thankful if anyone could share ideas what to check or give me advise where to find a list of cases when ECM start to drop RPM and shut down engine.

Thanks in advance.

i recommend the following as alot of BM's have problems with these following components in hot weather. all symptoms definitely heat related:
1-replace your ignition relay. see provided schematic. crosses over to ford and chrysler common a/c relay available at any auto parts store on the cheap.
2-using kano kroil or something similar....top quality stuff....lube both your clutch interlock safety switch and sidestand interlock safety switch if so equipped.
3-possible fuel pump short to ground. can only be verified by removing pump and checking for chafed wires. have posted on here numerous times how to drain frame, remove pump, check wires.
4-CPS unit possibly headed towards death row. it is behind the cam cover bullet. with bike at room temp and motor running normally start to add heat to the cover bullet with heat gun or hair dryer. USE COMMON SENSE HERE. motor change tone and note....eventually shutting off? faulty CPS unit.
5-remove entire airbox assembly including base plate. YOU MUST LEAVE rubber air intake horn attached to TB for running. start bike and bring up to temp. using method in step 4 add heat to the coil. motor changes note and shuts off? faulty coil. when doing this test YOU MUST leave the wiring harness attached to the IAT switch located bottom right rear of airbox base plate or you'll receive an active CEL light and stored trouble code.

Many thanks, mate! Will try to check all you've mentioned. Could you please some more details?

Quote:

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Originally Posted by lunaticfringe

1-replace your ignition relay. see provided schematic. crosses over to ford and chrysler common a/c relay available at any auto parts store on the cheap.

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Is there a way to check relay is it working fine or not? I'm in Russia so it's often hard to find parts in stock.

Quote:

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Originally Posted by lunaticfringe

3-possible fuel pump short to ground. can only be verified by removing pump and checking for chafed wires. have posted on here numerous times how to drain frame, remove pump, check wires.

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One of fellow buellers here catch this shortage problem with fuel pump but his bike burned the safety fuse every time he tried to start the engine. Do you think it is possible for same problem to appear with different symptoms?

Quote:

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Originally Posted by komarov

Many thanks, mate! Will try to check all you've mentioned. Could you please some more details?

Is there a way to check relay is it working fine or not? I'm in Russia so it's often hard to find parts in stock.

One of fellow buellers here catch this shortage problem with fuel pump but his bike burned the safety fuse every time he tried to start the engine. Do you think it is possible for same problem to appear with different symptoms?

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yes sir, always my pleasure. remove lid to your fusebox and look on underside of same. shows your 3 relays. remove the ignition relay. it is 20 amps. take to any auto parts store and match up. prongs must match up and minimum of 20 amps. on the fuel pump and possible chafed/shorted wires it will not always show a stored trouble code and will not always pop the fuse. typically does but not always. i mentioned it as a common source of problems on older high mileage bikes. tedious to check but something to consider. also keep in mind that your bike is 11 years old with approximately 37,000 miles on it and things are starting to wear.....things such as the fuel pump. a pump reaching the end of its lifespan tends to get lazy when having sat unused for a long period of time....and when temps get warm and the fuel in the frame gets heated. a lazy throttle and bogging down typical signs and symptoms of a weak pump. worth checking.

Quote:

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Originally Posted by lunaticfringe

yes sir, always my pleasure. remove lid to your fusebox and look on underside of same. shows your 3 relays. remove the ignition relay. it is 20 amps. take to any auto parts store and match up. prongs must match up and minimum of 20 amps. on the fuel pump and possible chafed/shorted wires it will not always show a stored trouble code and will not always pop the fuse. typically does but not always. i mentioned it as a common source of problems on older high mileage bikes. tedious to check but something to consider. also keep in mind that your bike is 11 years old with approximately 37,000 miles on it and things are starting to wear.....things such as the fuel pump. a pump reaching the end of its lifespan tends to get lazy when having sat unused for a long period of time....and when temps get warm and the fuel in the frame gets heated. a lazy throttle and bogging down typical signs and symptoms of a weak pump. worth checking.

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Thanks for help! Will try to get to workshop this weekend to investigate.
BTW today it's about 68F and had no any issues with getting to work through heavy traffic.

If everyone interested I've found the faulty part. Equipped with heat fan I've prepared to heat every single part of the bike to investigate.
And firstly I've decided to boil fuel tank. 210 degrees celsius applied for 5 minutes to the lower part or the frame and the engine stops working. To be replaced.