Ok, finally found some time to get back to this issue and...
First things first, after lots of Deep Creep, the clamp bolts came out pretty easily. Then the muffler rolled over and almost twisted out, all on its own. Yup, easy peasy.
Keep in mind the engine was swapped about 6,000 miles ago so although I didn’t think it would be welded in there, it did come out super easy. Which also makes sense if the muffler wasn‘t heating up to the correct temperature. The gasket was silver in colour on that outside edge. Not like the right side gasket, which is the dark black I expect.
So some thoughts:
1. There doesn‘t seem to be an obstruction in the muffler. I’ve blown air through both directions and it seems fine
2. is there a blockage in the header? Doesn’t seem to be. I was able to send a fish tape (gently) from the collector to the bend in the header
3. Didn’t see or feel a blockage in the header
4. Is it firing only on the 1 and 3 cylinders? Granted I’m coming from a twisted twin GL650 but it pulled hard, got good mileage and never complained. Temps were as expected
5. Could the timing belt challenge, which is on this
thread, be contributing?
Any bright ideas out there?!
Thanks!