Inline filters are the kiss of death. They don't work well with gravity feed systems

Forgive my ignorance but I'm unfamiliar with inline filters generally or the performance issues they may pose due to air pockets, restricted flow, etc.

It seems based on the last two posts the filter is the issue here. I'm between stops with work. I'll get a straight hose and report back.

I run a vm36 carb by the way.

The fuel line and factory petcock/carb nipples are large enough that that an air bubble can freely move upstream and exit the fuel system.  The small fittings on the fuel filters are small enough that the bubble can be trapped and will not freely exit....the fuel wants to come down through the nipple on the fuel filter - but I believe the surface tension of the fuel is stronger than the small air bubble - and the flow stops.

This situation evidently can happen during normal operation, and some members have even had this occur after using a fuel filter for months period.  When they first install the new fuel filter the tubing the line is empty - and the fuel flows down the tube and pushes the air out the bottom.  After that the fuel system is subject to periods where the bike is not being ridden and air gets into the system from the carb end and the air travels up the tubing until it reaches the small fuel filter inlet.....and that is when the bubble gets lodged and stays.  The rider is suddenly at a loss as to why his bike has stopped running, and he starts looking for electrical problems and carb problems that don't exist!

The stock and the Raptor petcock both have a fuel filter screen in the tank......and the carb has a fuel filter screen on top of the seat for the carb needle.  If both of those are in place and working....I really don't see the need for a third filter - especially when they can be problematic.

If you are going to run a fuel filter - get one with with the largest diameter hole you can find, and mount it as vertical as possible.  The attached photo shows the difference in hole size for the inlet nipple on the carb and the hole size in a 5/16" plastic fuel filter.....you can plainly see the size difference - evidently the smaller size is easy for an air bubble to get stuck.

Before you open her up and check the clutch, check your oil and make sure gas didn't get into the crankcase from a flooded carb.  This happened to me on my old S40.  I caught it in time and didn't have to go in and clean/deglaze the clutch plates/discs.  Fresh Shell Rotella T4 fixed my issue.  Hopefully it's something simple.

I was able to just do an oil change and resolve my issue.  If you have to clean the friction disks, there are different schools of thought, but light sanding (not aggressive) is my suggestion.  I used a nylon brush on some of the more stubborn glazed/shinny areas.  Dawn and warm water and dry in the sun if you can.  Some people use gasoline, kerosene, and other solvents.  But if gas fouled them up, why would you try to use gas to clean them? (just my logic).  Perhaps someone with more experience than me can chime in.

It's not lean -- it sounds like it's running rather well actually it's just my RPMS aren't matching my speed. Rpms climb without power to the rear it's actually like struggling to go past 60 at WOT, seems to be getting worse every time I run it.

Surviving Philly wrote on 04/10/24 at 09:00:26:
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Yeah, that sounds like a badly slipping clutch.  You said it was relatively new.  It might have been improperly installed, improperly adjusted, or both.  Or the wrong oil.  It's likely fired if it's slipping as badly as it sounds.