Dismantled the other gen II muffler from the opposite side--inlet cone better than the first one, still sold but a fair amount of surface rust.
Set of Gen I's to use as the donor for a core replacement.
Inside the gen I. I could just unroll the fiber packing from the gen II; the gen I seemingly had no end to start unrolling so I had to cut it. You can see the multiple layers of fiber packing then the steel wool around the core. Gen II shown along top.
The steel wool from just one can.
Direct comparison of cores. Gen I near, Gen II far.
Perf tube material is 1mm thick. Gen I is 60mm OD x 58 mm ID (~2-3/8" OD x 2-1/4" ID). Gen II is 45mm OD (~1-3/4" OD). Overall baffle length is 385mm (~15-1/8"). Note the perf tube or reducing cones go OUTSIDE of the stub tube in the end caps, so the ID is what is critical. I believe Nemo reversed this due to US size availability & stuck the perf tubes INSIDE the end cap tubes instead.
Comparison of end nozzles; gen I is short, gen II is long.
All broken down.
Pair of Gen I cores as solid as the day they were born, ready for transplant. Glad no one picked these up before I got to them.
The end caps are siliconed to the cores so first time removal takes a lot of effort--especially not to crush anything since both can materials are so thin.
Carbon is about 0.039" thick, Ti is about 0.027" thick. End caps about 0.049" thick.
It is easier to cut yourself on the edges of the carbon than the metal.
Without cores or packing the carbons are so light they just might float away.
5/32" is the drill bit to use to drill the rivets; smaller & it may not get the head off before it starts spinning. Any larger & you risk enlarging the holes.
Gen I used aluminum rivets with a 12mm (0.473" head).
Gen II used stainless rivets with a 8mm (0.313" head).
I don't anticipate gen I cores to be problematic in any normal/reasonable scenario. Unfortunately a poor/low grade (or batch) of SS negatively affects the reducing cones of gen II.