We needed to quieten the Invincible Jap down.
There was little chance that the current exhaust system would go UN-noticed in the USA so we decided to build a muffler.
A good pal was tasked with this and the photos below show the basic steps.
To keep with the style of the period, we pressed the JAP logo into the front of the muffler.
I must say that i was a little hesitant at this, as i thought it might be a little over kill, but it certainly does not look out of place.
The machine used is a Power hammer, and these are really cool machines to use.
They have a fixed anvil on which a movable hammer oscillates about 3500 / Min and this stretches or shrinks the metal.
They are a use full tool for sheet metal construction and anyone skilled enough to master this machine is always in demand.
The photos show the construction better than words.
Once this muffler was fitted the slip in tail pipe can be moved laterally to set the back pressure and obtain the required note on the bike.
It has gone from a high noise to a deep dull Boooob de da Boooom, Boooom de da etc.
It actually sounds quite neat.
The finished result is a neat custom muffler that certainly doesn't look like and afterthought.
More importantly it actually works better than anticipated, with the period appeal and can be altered to tune quite easily.......
I hope that those reading this Blog can take note of the muffler when they view this machine.