Some months ago (it was here actually), I talked about the reproduction exhausts I purchased from Marcel at Classic Suzuki Parts NL , and while I did have a few issues due to shipping damage, these were quickly sorted out and I put them safely aside till I needed them. With the engine running and most of the build complete, it was time to fit the brand new exhaust system to the bike and then stand back and admire it ! Life is never that easy however, and predictably I ran into another few issues during the install which are worth flagging so that others are not caught unawares.
I had said that they were the correct shape – as it turns out I was wrong. My wife tells me that often, so perhaps sometimes its even true ! 
The shape is correct, the ‘dimples’ are in all the right places and the diameters are correct, but there are actually two issues that caused me a lot of phaffing about to sort through:
- the flanges/seams on the welds are far too wide
- the hanger mount on the muffler is off by about 4 or 5 mm (the old ones are about 33 mm off the centre line, and the new ones about 28 or 29 mm)
This meant that when mounted on the bike, the mufflers I received (I have no way to know if this is true for all the ones Marcel sells) were tight to the lower frame rail, and the lower weld flange was in the way of the side stand so it could not be mounted. In the photo below, the arrow points to an original muffler on the top and to the lower weld flange/seam – you can see its almost non-existent. On the reproduction muffler below it you can see that the flange is quite wide and extends about 8 mm further than the one above.
To fix this, I had to shim out the muffler at the hanger using some stainless washers so that when bolted up it would just clear the lower frame rail, and I then used a block of 9 mm stainless steel plate to shim the side stand so that the side stand pivot bolt can clear the under side edge of the muffler. That actually has a positive effect as it means the bike stands a bit more upright on the side stand now, so it isn’t all a bad news story.
So to sum up, were I to do it all over again I’d still buy from Marcel – they do look and sound fantastic (Marcel’s pipes have the metal mesh in the forward pipe area that Develkic neglected to install in their GT750 pipes making the Develkic pipes sound tinny) and are a well made, quality product. It is just that as with most British bikes, ‘some fitting’ is required’. 