Sudden Cut Out Low Speed

mikesim · Jun 24, 2021

Hmmmm... I've never seen my temp gauge go above half. That is usually the point where the cooling fan cycles on. There seems to be a trend in this discussion about heat related issues with similar symptoms. Also, the NT is getting rather long in the tooth agewise if not mileage wise. There could be component(s) that are beginning to fail due to age. I've never had Traveller act up when I've had him in the shop at home where I have the test equipment so I've never been able to pinpoint anything and no MIL displayed to guide me.

Mike

NewTo700V · Jun 24, 2021

The sensors utilized on PGM-FI bikes are more robust than they're getting credit for. I have some ancient PGM-FI Interceptors that will qualify for antique plates soon. That V4 engine is a blast furnace compared to the NT and all sensors are still doing their job.

Brillot2000 · Jun 24, 2021

I am not familiar with the climate of Wyoming or if it is humid that way. Also, what were the elevations where Phil was experiencing his issues at?

This is a theory not backed by any evidence:

Fact - Hot air is less dense

The ECU monitors the airbox's incoming air temperature and many other parameters from an array of sensors.

What I think is that the less dense air was causing the bike to run a little bit hotter than normal. The ECU was reading and reacting to all the data it was receiving. Thus, causing the bike to act as it was. Dropping a gear brought the engines revs up and to move more air through to help with better combustion and reducing the coolant temperatures.

I honestly think Phil's issue created by multiple factors. Typically less dense air does not foster good combustion. Increasing the volume of air coming into the engine helped with better combustion and the engine smoothed out.

Again, this is just my theory.

DirtFlier · Jun 24, 2021

Phil also had a large Mexican lunch a few hours before. :rofl1:

mikesim · Jun 24, 2021

Brillot2000 said:
I am not familiar with the climate of Wyoming or if it is humid that way. Also, what were the elevations where Phil was experiencing his issues at?

This is a theory not backed by any evidence:

Fact - Hot air is less dense

The ECU monitors the airbox's incoming air temperature and many other parameters from an array of sensors.

What I think is that the less dense air was causing the bike to run a little bit hotter than normal. The ECU was reading and reacting to all the data it was receiving. Thus, causing the bike to act as it was. Dropping a gear brought the engines revs up and to move more air through to help with better combustion and reducing the coolant temperatures.

I honestly think Phil's issue created by multiple factors. Typically less dense air does not foster good combustion. Increasing the volume of air coming into the engine helped with better combustion and the engine smoothed out.

Again, this is just my theory.

The NT has a MAP sensor I believe which will compensate for altitude. Even though it was extraordinarily hot the NT should have still performed correctly. On one of my Western safaris several years ago I rode through Death Valley and US 50 through Nevada and Utah in similar temps and Traveller performed flawlessly. Something else is going on.

Mike

Brillot2000 · Jun 24, 2021

mikesim said:
The NT has a MAP sensor I believe which will compensate for altitude. Even though it was extraordinarily hot the NT should have still performed correctly. On one of my Western safaris several years ago I rode through Death Valley and US 50 through Nevada and Utah in similar temps and Traveller performed flawlessly. Something else is going on.

Mike

I live in LA. Back in summer 2019, I rode in 118° ambient temperatures riding home from work. NaTalie performed flawlessly in that heat, I did pretty well myself wearing all my summer gear.

Perhaps there's a condition that we are not aware of regarding Phil's issue.

Phil Tarman · Jun 24, 2021

DirtFlier said:
Poor fuel quality?

I doubt it. I'd filled up with Exxon in Casper about 190 miles before. It had been around 100F for about 140 miles and my elevation had been between 6000-7000 ft. I was down under 4000 ft when whatever it was happened. It is more humid than it had been for the first 100 miles, but still not terribly humid.

???????????????

mikesim · Jun 24, 2021

I am flummoxed at this point, just keep an eye on it. Hopefully whatever it is will trigger the MIL, but not leave you stranded.

Mike

ARKNT · Jun 24, 2021

Phil did you happen to see your voltmeter during the surging? It seems a longshot but since you posted the volts had shifted a bit, if the voltage regulator went crazy it could cause many odd things to happen.
Sounds fuel related but you need volts to run the computer and open injectors.

Brad

Phil Tarman · Jun 24, 2021

Brad, I wasn't paying attention to the volt-meter right then, but it had been running pretty steady at 14.4-14.5.

mikesim · Jun 25, 2021

ARKNT said:
Phil did you happen to see your voltmeter during the surging? It seems a longshot but since you posted the volts had shifted a bit, if the voltage regulator went crazy it could cause many odd things to happen.
Sounds fuel related but you need volts to run the computer and open injectors.

Brad

Good point! Keep an eye on the voltmeter if and when it acts up again.

Mike

ARKNT · Jun 28, 2021

Phil Tarman said:
Any ideas??

Phil I think you caused this problem yourself.
You named your bike horse. Of course a horse wants to buck sometimes.
Hope it keeps running smooth.

Brad

Phil Tarman · Jun 29, 2021

ARKNT said:
Phil I think you caused this problem yourself.
You named your bike horse. Of course a horse wants to buck sometimes.
Hope it keeps running smooth.

Brad

Brad, I hadn't even thought of that! At any rate, I'm glad it hasn't bucked any since then. It ran fine for the 801 mile trip home.