Chokes/Bogs down at mid-upper speeds (newbie)

[Busbis]

Alright this is very insightful. I'm researching what a "proper baffle" would be right now. Also is this an eBay buy? I mean my previous one didn't even have that hollow tube inside, just the circular metal plate with the hole in it.
The bike has always backfired, although it backfires especially a lot now. For now I'll use the bike without the fuel filter, however I'll most likely be getting a larger one to hold off carb work.
Should I look into what I need to do to jet it properly? Also if anyone is available this weekend I'd love the assistance!

[Busbis]

Turns out the issue was the baffle.

Put in the baffle today, began to ride and it was the exact same.. So I thought there goes another idea.. However as I kept riding on my way home, it got incrementally better. I kept riding and sure enough it built back up to what it was initially! I guess it had to build back the back pressure? So as of right now the issue is resolved.

Thank you for all the responses!

[60ratrod]

the baffles should have had an almost immediate effect.

[JTGS850GL]

As stated earlier... The #3 plug is running VERY LEAN if it's even firing at all!!! Any changes you made to the exhaust will have no slowly changing characteristics. "Back pressure" is not something that changes slowly. I'm betting that your bike has never run right since you've picked it up and things are only getting worse.

If it were my bike, I would start with a good carb cleaning and synchronization, verify all electrical connections (especially those related to your ignition and coils) and do a proper valve adjustment. Running it without doing the basic maintenance is a good way to destroy a good engine.