Very sick 1300 - Need advice

My bike is at 1/2 power and I can't find the cause.
I'll keep this as short as possible . . . This all started as I was riding from work on the tollway at 70 MPH, after 10 minutes at speed my 05 ST1300 suddenly started to bog down to the point I could maintain 60 mph but could not accelerate.
This lasted about 5 minutes and I treated the symptom as if I had some bad gas with about 1/4 tank left. I rode out the tank after adding some Seafoam, then filled up with fresh gas and the problem seemed to clear up. 2 days later I started up to go for a ride and the bike would not idle, I had to turn up the idle adjustment all the way to keep it running. The bog problem returned and after riding about 10 minutes, it seemed to clear up but still had the idle problem. Now the bike won't run right, can barely accelerate and just sounds sick. Here is what I have addressed.

- I checked the mufflers, they are fine. This is a symptom I have seen before with plugged CATs.
- The fuel pump runs and pressure is good at 48 psi at idle
- The MAP sensor checks OK
- All hoses for the MAP circuit are clear
- The spark and timing is OK.
- The valve adjustment is within .0005" on all valves
- Compression on all cylinders is good
ADDED:
- The bike is disassembled to the basic engine block, the engine starts and runs on all cylinders and will rev to the redline, but has no power. Even without the mufflers it doesn't sound like it used to.
- No problems with the air filter, all that was clean.
- I tried my spare set of spark plugs, no change, and have new iridium plugs ordered.

My best guess now is a fuel supply issue. I am about to pull the upper and lower fuel tanks and check for debris and do a visual check on the fuel pump and filter.
The only other thing I can think of are the fuel injectors.

Any suggestions from the group?

I'd still not rule out the fuel pump. They can check good and still present problems after a bit of engine run time (BTDT).

You can also check plugs (wouldn't hurt to replace or swap to an old set) and coil grounds/resistances--coils and their grounds can act fine in the shop, but can present problems after a bit of engine run time.

All fuel injector connections clean & good? Fuel injector sub-harness main connector clean & good? May want to reseat those to be sure.

Sounds like an air/fueling fueling issue. I would look at the filters first:

(1.) Look in and under the airbox. Check for a dirty air filter and signs of mouse visitors

(2) Drain all fuel, then go ahead and change out the fuel filter, and look real close at the fuel pump while in there. Alternative replacements are pretty cheap.

(3) Refill with fuel from a name brand frequently used gas station.

Your problem sounds like the fuel pump is not staying at the proper pressure and may need to be replaced. Good luck and keep us posted on your findings.

Are the cats the same color? I had a similar problem a year ago and it was a loose or corroded terminal fitting to a coil causing 2 cylinders to go off-line. The visual clue on my bike was the episode of poor power, though lasting only a couple of highway speed minutes, caused one cat to discolor. The other side was normal. Under the coils the mounting bosses the 8 mm bolts go through were rusted.

It's always cured by Seafoam, LOL.

Is it throwing any codes?

No codes? I'd go with bad gas/fuel pump....strange you get no codes.......good luck....injector cleaner is your friend and drain the tank...ff

Can you hook up your fuel pressure gauge somehow and test ride it?

There are links in here that may help:

https://www.st-owners.com/forums/showthread.php?136449-Loss-of-power-unusual-coloring-of-catalytic-converter&highlight=

Sounds like what my 07 did when the fuel pump was failing..

During my replacement of my body panels this fall, I disconnected a coil wire. The bike ran at half power, barely idled. When taking off it seemed like I was in 3rd gear. RedST pointed me to the coils as it happened to him. Now yours is acting up without having removed the body work, but do not rule out the coils as others have said, corrosion. Tough to pin point one item, but this one is easy to fix by cleaning all connections and mounting bolts.

you have a PM.

Check the flow as well as the pressure while you're in there.
The fuel pump can pass for pressure and fail for volume.

A bad battery can cause this as well.
A failing stator will also.

I agree with many that the fuel pump sounds like the issue. Check the pressure not only at idle but also at higher rpms.

The symptoms seem to fit most to the fuel pump - needs higher throttle to maintain speed. Works one day and not the next.

You did not mention how many miles on the machine.

My suspect is the fuel pump as well. Often a fuel pump problem will be intermittent; you may have tested it while it was working fine. Often they will fail after things heat up and if left overnight they work fine again the next morning.

The first thing that JUMPED OUT AT ME was the fuel filter is plugged and or coming apart. But what would I know, I'm just a Girl.

Followup / Update for reference of similar symptoms . . . .
I think I found the reason for my bike running the way it was, but I'm still not sure of the cause. I put my ST back together with a new fuel filter, new spark plugs and a starter valve sync. All other components and systems were checked and found to be good. While I was cleaning up the bike before assembly, I notice the oil sight glass was totally covered. So I drained out enough oil to put the level back at midpoint, and that took removing a about 1.5 quarts. Thinking back, now I think the high oil level was the cause of the extra drag on the motor and strange noises (crankshaft working the oil), but that does not make sense.
IT has been about 2,000 miles since my last oil change and the bike has been running fine until the last 60 miles, and I am meticulous about how much oil I put in the bike. There are no signs for where the extra fluid came from, the coolant levels have not changed. I drained all the oil and replaced it, there is nothing in that oil that indicates fuel or coolant could be added.
The bike runs great now and I am going to keep an eye on everything, a few hundred miles should indicate what I think I found.

Highrider said:

Followup / Update for reference of similar symptoms . . . .
I think I found the reason for my bike running the way it was, but I'm still not sure of the cause. I put my ST back together with a new fuel filter, new spark plugs and a starter valve sync. All other components and systems were checked and found to be good. While I was cleaning up the bike before assembly, I notice the oil sight glass was totally covered. So I drained out enough oil to put the level back at midpoint, and that took removing a about 1.5 quarts. Thinking back, now I think the high oil level was the cause of the extra drag on the motor and strange noises (crankshaft working the oil), but that does not make sense.
IT has been about 2,000 miles since my last oil change and the bike has been running fine until the last 60 miles, and I am meticulous about how much oil I put in the bike. There are no signs for where the extra fluid came from, the coolant levels have not changed. I drained all the oil and replaced it, there is nothing in that oil that indicates fuel or coolant could be added.
The bike runs great now and I am going to keep an eye on everything, a few hundred miles should indicate what I think I found.

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When you change the oil fill it with one gallon and go ride, that will keep you from over filling it.