question/request for riders of 2018-23 panigale v4 and or streetfighters

im having a problem with vaporlock and have identified the source of the problem, but i would like ask of you guys the next time you ride, after your stop and it sits for minimum 10 minutes
put your ear to the tank and listen for gurgling/boiling, sometimes fuel will boil as low as 100 deg F. and these things run hot

so the best way to know which is which

1. if you hear bubbling but are not sure if its boiling or bubbling vapor pressure back through the feed line. if your bike is hard to start after riding and letting it sit for at least 20minutes you have my problem. maybe just not to the same severity..by hard to start i mean it takes 5 to 15 attempts to get it to start. and once it starts it runs rough and stumbles for a few seconds (the rough running is the air coming out of the fuel lines)

2. if after 20 minutes your pangiale v4 or streetfighter fires right back up 1 to 2 start attempts ..with no problems idling then your bubbling was just boiling of the fuel and you dont have my problem.

if you guys who can reply please do the above and post your year/ v4 or streetfighter, by doing so maybe i can isolate if there was a change in design or maybe i need to buy a newer pump assembly or maybe i just got a dud pump which happens or theres a certain year and model that does not suffer from any of the symptoms

What year is your bike? There was a (well several really) problem(s) with the 2018 Pani V4. I had a 2021 Pani V4 with zero issues.

2019, my year was affected by the recalls from the fuel splashing stalling etc etc...but all the necessary recall work was done by a dealer. i was thinking by a new pump assembly but theres no way of knowing if im getting a newER ASSEMBLY or one that came off the assembly line around the same time my pump assembly did and ill be paying alotta money for the same problems. unless i got a used one that i know for sure came off of a 2021 bike.\

Zero issues. V4S Pani 2020. I;m in the Eu with 95oct gas minimum, 5% AL standard. Don't know if that matters.
Starts like, bam.
I hear all kinds of things when I shut it off. There are so many elements cooling at different rates. I'll listen carefully next time for that specific. Interesting.

Vbreeze said:

Zero issues. V4S Pani 2020. I;m in the Eu with 95oct gas minimum, 5% AL standard. Don't know if that matters.
Starts like, bam.
I hear all kinds of things when I shut it off. There are so many elements cooling at different rates. I'll listen carefully next time for that

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Glad your not having Issues maybe 2020 is when they might have changed something in the fuel pump assembly. I'm not sure but if you would give it a little listen. Put your ear to the tank and see if you can hear that gurgling which is probably just the fuel vaporizing or boiling in the tank if. You're not having starting problems after 20 or 30 minutes and it starts as quickly as it sounds like it does. Then you definitely don't have the leaks that I have in the fuel pump assembly.

the link below shows where my assembly is leaking, ive done some things that may have fixed it, im waiting for a hot day to really get the heat in the lines during heat soack after shutdown, which is when its vaporlocking. it is/was depending on whether or not my mods worked to the point where i could reproduce the no starts easily.

Last summer in 36C, no issues. Starts even faster when hot actually.

Vbreeze said:

Last summer in 36C, no issues. Starts even faster when hot actually.

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Side Conversation: @Vbreeze If I remember correctly originally you had a Pani V4 (non S) if so like you I have now given up my Pani V4 and waiting for a Pani V4S

Ciao, Carmelo.

@cavlino
Ah the old S conversation. It has been wildly debated. Yes I have a V4S and I love it.
Congrats on your new bike on the way.
Discussion: Electronics suspension
I like it because the riding I do varies so enormously. I go from goat trails to race track. At the track I've learned turning off dynamic suspension is a lot better. Too many variables to understand how to optimize in dynamic mode. On the street, dynamic mode; in sporty mode, dynamic off. Girl on back, dynamic on.
You'll have to see how it fits you.

Vbreeze said:

@cavlino
Ah the old S conversation. It has been wildly debated. Yes I have a V4S and I love it.
Congrats on your new bike on the way.
Discussion: Electronics suspension
I like it because the riding I do varies so enormously. I go from goat trails to race track. At the track I've learned turning off dynamic suspension is a lot better. Too many variables to understand how to optimize in dynamic mode. On the street, dynamic mode; in sporty mode, dynamic off. Girl on back, dynamic on.
You'll have to see how it fits you.

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@Vbreeze Thanks for the tips on the settings you use!

Vbreeze said:

@cavlino
Ah the old S conversation. It has been wildly debated. Yes I have a V4S and I love it.
Congrats on your new bike on the way.
Discussion: Electronics suspension
I like it because the riding I do varies so enormously. I go from goat trails to race track. At the track I've learned turning off dynamic suspension is a lot better. Too many variables to understand how to optimize in dynamic mode. On the street, dynamic mode; in sporty mode, dynamic off. Girl on back, dynamic on.
You'll have to see how it fits you.

Click to expand...

Do you use the standard settings for fixed mode? I noticed they are quite different depending on which ride mode you are in.

Vbreeze said:

Last summer in 36C, no issues. Starts even faster when hot actually.

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i noticed as well in colder temperatures mine starts faster and easier always on first attempt, but for sure it never vapor locks the fuel feed line in colder weather... they must have changed something in the pump assembly for 2020, possibly adding heat shielding over the valve cover or pump assembly, possibly even changing the type or formulation of the plastic used for mold injecting the base of the pump assembly to prevent heat expansion.

bp_SFV4 said:

Do you use the standard settings for fixed mode? I noticed they are quite different depending on which ride mode you are in.

Click to expand...

Good question @bp_SFV4 and I know its for @Vbreeze and I started this derailing of @1hander post but I should also try and stop the derailing Please start another thread regarding the Suspensions settings.

bp_SFV4 said:

Do you use the standard settings for fixed mode? I noticed they are quite different depending on which ride mode you are in.

Click to expand...

Ya, no way "standard," hell no. I PM'd you. 6 to 8 different settings. You need to get it set up with a real pro or it sucksbllz. That's a very good spend.

1hander said:

They must have changed something in the pump assembly for 2020, possibly adding heat shielding over the valve cover or pump assembly, possibly even changing the type or formulation of the plastic used for mold injecting the base of the pump assembly to prevent heat expansion.

Click to expand...

The 2018 pump is the same as the 2022 pump, they have identical part numbers.

Lots of other things have changed though.

You can look at the factory parts diagrams and part numbers here to compare:


2018




2022

cavlino said:

Good question @bp_SFV4 and I know its for @Vbreeze and I started this derailing of @1hander post but I should also try and stop the derailing Please start another thread regarding the Suspensions settings.

Click to expand...

This isn't Reddit. Relax.

i saw that the part numbers were the same

1hander said:

i saw that the part numbers were the same

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For the fuel pump sure.

Where there revisions to the tank numbers or breather assembly part numbers though?

sorry i meant for the pumps... im 99.9 percent convinced its the pump assembly leaking. i did look for extra heat shielding around the pump assembly area and saw non up to 2023
the tanks on the newers have a different part number, all i can see is they added 2 more mounting tabs towards the front of the tank. breather lines are in the same place. internally i cannot tell.

if my fixes do not stick in the heat, then my next option will be to just but a used pump assembly, the newest i can get and see if that fixes the leaking problem..

@1hander, like @Vbreeze I too use my early 2018 V4S (production Q4 2017), with zero starting issues for now 30.000KM/18.500miles.
I too ride her anywhere in Europe from city traffic, mountain roads to occasional race tracks.

Actually, she started her life for the V4 Euro-launch campaign as one of the first V4’s rolling out of the Bologna factory as a Dutch press bike. I bought her with 4000km/ 2500miles on the clock.

Besides her also having received all recalls and updates under warrantee, being an early production bike, she also has quite some metal ‘prototype’ parts bolted on which were replaced by Ducati in later production bikes for standard less robust plastic parts, as can be found in the parts catalogue for a 2018 V4S.
Typically Italian, even while under Audi QC for more then a decade, this differs from part2part as my Duc dealer confirmed from servicing her. lol

In general, most products constantly receive revised/ different parts even within one model generation (e.g. due to recalls, change of/ more then 1 part-supplier for same partNo., required cost-cut, part-revision). So for a non-insider it will be quite hard to determine when a specific part was replaced by a succeeding part. With more than 1 production line a/o factory-inventory, part2part specs can even differ between bikes of same model and within same assembly-week!

So even if I’m able to hear these bubbling/ gurgling sounds, I don’t know and can’t tell without removing the tank assembly and visually comparing the specific part(s) you are having trouble with, if mine has the same official partNo’s. or a differently manufactured, pre-production/ prototype, part installed instead.

Hopefully this helps your analysis, not to add more confusion as to which parts were revised when by DMH?

One last note, contrary to @Vbreeze, I always refuel with fuel with the highest available octane and lowest % of ethanol (E5), to have best possible performance, mileage and engine protection.
Effectively, in Holland this means refueling with 98RON (E5) and in Germany with ‘racing’ fuels with RON100+ (E5).

Turbo engines and highly tuned naturally aspirated combustion engines, like the V4, will perform better, safer and (i.e. turbo’s) arguably last longer with these performance fuels.

@1hander may be the gurgling/ bubbling sounds become less when using higher octane performance fuels?
Good luck finding a permanent fix.