Pipes Welded

I picked up the pipes from the welders on Friday
and test fitted them, Fit perfect!
Next on the list is a big cleanup in the garage
and get the gear change linkage fitted then fit
the electrics and loom.

Pipe ready for Welding

After sourcing a suitable length of pipe with
the correct bore I cut a section with angled ends
to extend the end can of the left pipe to clear the
swingarm. The end can will be extended by about
70mm. The original internal stinger has been cut
to be welded in place where it would normally be
with the other end with the silencer being able to
fit back into the end can. The stabilizer strap will
have to be remade to span across the 3 sections
of pipe.

The images below show the pipes taped up to give
an impression of the layout/run of the pipe. [its a bit saggy!]

Exhaust run

I made a start today about stripping the frame totally while
the front end was off. I flipped the frame and installed the
engine cases with the barrels and heads in order to finalise
a solution for the left side exhaust pipe. I think I have
sourced a suitable bit of mild steel pipe to extend the
silencer past the swingarm.

Left Pipe Extended

I took the plunge and cut the end can off the
left hand exhaust. This enabled me to mount
the main body of the exhaust to the engine/frame
to check the side stand clearance and spring
location.

The end can will have to be extended by a minimum
of 125mm to clear the swingarm. The image below
shows it extended fully by about 200mm. This also
places it wider than before.

End Can Extender

Another option and probably a more suitable one
is to extend the end can past the point of contact with
the swingarm. Photoshop estimation below.

Exhaust Run Fine Tune

In order to get the side stand clearances sorted
the Exhaust run really has to be finalised.

I cut a length of pipe to simulate the header length
and offered it up to see how the exhaust on the left
sat. There are two issues,
[1.] the inside rib on the Micron exhaust clashes with
the cross bar of the frame but this can be ground
down to clear in that particular spot and welded to
re-seal if needed, this will also have to be done with
the right side too.
[2.] the end can as mentioned before clashes with the
swinger which is wider on the left for the chain run.
I am planning to slice a piece off the inside at a
straight angle and weld a flat piece back on. This will
only affect the padding inside and not the baffle itself.
it shouldn't be too much to remove, approximately
20mm in and about 50mm in length . . .

Exhaust Run

temporarily fitted the pipes to check clearances
here is how it should look . . .

because the exhaust ports are angled inwwards
it looks like the cans  will clear the swingarm.

blow out

next step was to apply heat to the damaged areas with the aid of 2 butane/propane blow torches to soften them metal for the internal air pressure to push out the dented areas.

I got the first pipe fairly well sorted with a few of the deeper scores still visible, The second pipe was more of a challenge as the damage was greater . . . and I ran out of gas!

pumped

Next step was to plug both ends of each pipe after removing the baffles pressurized with air from a foot pump.

I used 5mm steel plate and an old bicycle tube as a seal with various brackets and clamps. I was able to get the pressure up to 80psi.

compressed expansions

A major concern for me was the whole topic of the expansion chambers, firstly sourcing a set and secondly fitting them with the non native frame present.
I managed to source a set from a forum member on RDnuts . they are a pair of early Microns under the name "Codnor Micron" with short can silencers. They have been  involved in a meeting with a foreign object at the diffuser point and need to be repaired.