We build custom motorcycles so that we create something truly individual. An important element of this individuality can be the exhaust system.
Most customisation projects use already existing original equipment manufacturer (OEM) or after-market exhausts. By their nature these are neither unique nor do they offer flexibility in terms of style and fitment.
At 2WheelsMiklos almost all of our customisation projects have gone one step further in that we have fabricated completely one-off exhaust systems. This offers the customer the chance to describe exactly what they are looking for, the finish they want, the routing and the fitment. All our systems are welded up from medical grade stainless steel pipes and bends. We also fabricate bracketry as well as baffling and silencing to “taste”. Finishes are typically brushed (satin) or polished stainless steel. Where we use parts of the existing system this can combine with chrome or if the existing system no longer looks great, also wrap. Some mix and match also occurs – in particular combining with GP Style tail pipes. These are robot welded pipes and are produced in China and can be bought on EBay relatively cost effectively (£220 to £280 including duty). It is not possible to emulate the precision welds without robots. GP Style tail pipes are very popular at present.
Good examples of our systems are (see also pics):
Two-into-one plus GP Style tail pipe on Mule Thruxton
High level brushed on Bonneville Scrambler
Header pipes on Rocket Bobber (mated to chromed XS75 Hurricane tail pipes)
Six-into-one on Valkyrie Custom (using two header pipes originally prepared for BMW K series triples)
Apart from bought-in components (such as the GP Style tail pipe) the material cost for one-off pipes is fairly low. However, depending upon the complexity, workshop hours can be a couple of days to a whole week – as each system is truly individual. Wherever possible we use existing bracketry (eg footrest hangers) to minimise overall cost.
Three further areas tend to generate questions:
MOTs: Loudness is in theory only an advisory on an MOT. So you should not fail your test if you have louder pipes. Baffling of course is always available.
Performance with Carburettors: Typically custom exhausts are much more free flowing than the OEM pipes and are also in most instances mated to free flowing pod air filters (versus the more restrictive OEM airbox). In carburetted bikes this should in theory mean the need for more fuel (to keep air-fuel ratio constant) – hence bigger jets. In practice we have found this only to really apply to some fours – with twins (parallel and boxer) being relatively impervious to the changed conditions. On the other hand the experts advise never to mess with the airboxes on classic Japanese fours. Of course these are in reality replaced but this could well mean a fairly arduous process of testing for better suited main and pilot jets and setting up properly for hot and cold starts. In reality the original smooth running is almost never again achieved through the full rev range and in every gear. For all free flowing exhausts it is normal to have the odd “pop and crack or missed beat”. The price we pay for being unique.
Performance with Electronic Fuel Injection (EFI): In theory EFI bikes are much easier. The brain (ECU) calculates the correct blending of fuel and air and there are no other worries. In practice this is true for all but the most modern EFI bikes. Today’s machines are now super electronic and require detailed computer diagnosis/mapping in order to comply with ever more rigorous emissions standards. So for the very new bikes probably best to stick with OEM and OEM recommended pipes.