Replacing exhaust systems are generally a simple process as an exhaust is only held together by a couple of clamps. Replacing factory fitted exhausts with a branded aftermarket exhaust is one of the first modifications that motorbike enthusiasts tend to do, it also gives the engine a couple extra bhp (Brake Horse Power)
Motorbike exhaust systems are split into three sections
Back box/Muffler/Exhaust can
Manifold/Header -The manifold is generally secured with two bolts, if you are working on a old bike use WD40 or another lubricant and allow enough time for the oil to soak in before attempting to remove the manifold bolts. This is because the manifold reaches very high temperatures meaning the metal bolts expand/contract with the heat and cooling process.Remember to remove the gasket too.With the bolts from the manifold removed, work your way down to where the manifold connects to the mid pipe. Remove the necessary clamps/fixings, normally a nut and bolt securing each exhaust section together.
Midpipe -The mid pipe joins the manifold to the back box, it is the easiest to remove of the three sections. Remove the bolt that connects the mid pipe to the back box followed by any other necessary clamps/fixings on the mid pipe.Remove the section of pipework, take note when removing an exhaust section of any gaskets that need to be replaced. If nothing falls out from the ends of the exhaust, then have a look inside the ends of the exhaust pipe for a stuck gasket if necessary. This will inform you if a gasket is needed or not.There should only be a back box left to remove.
Back Box/Muffler -The back box can be replaced separately from the rest of the exhaust, but this guide is to show you how to replace the whole exhaust system, so you can understand how to replace all sections of the exhaust.It will be bolted in place by one big fixing (hanger) that is normally hidden underneath a body plastic. Remove the bolt so the back box will come away from the motorbike.With all the exhaust and fixings removed ready to be replaced with the new ones, take this opportunity to clean any areas you couldn’t access with a fitted exhaust.
Fit the new pipe work (in reverse order of removal) replacing any gaskets to keep the exhaust fumes within the pipework. The best tip we can offer is to not tighten the exhaust fully until it has be fitted finger tight. This is because the exhaust may need movement to allow a perfect fit.Start with refitting the manifold ensuring that you have replaced the gasket, only tightening the bolts a hand full of threads.
Slide the next piece of piping over the manifold pipe, again only tighten it a couple of threads to the bike frame.
Finally slide the back box over the mid-pipe and secure it to the bike frame fully. Now that the backbox has been secured to the bike frame, work your way back down the pipework securing every nut and bolt all the way to the manifold.Doing this will ensure in the exhaust system being fitted correctly.
When the whole exhaust system has been fitted, it is highly recommended that you clean any marks off the new exhaust because once that exhaust has become hot any marks that are on the exhaust will remain there forever. (even fingerprints)Test the exhaust system for leaks by switching on the motorbike and feeling the exhaust joins for air escaping (BE QUICK AS THE EXHAUST SYSTEM GETS HOT).
If no air leaks then it’s a job well done, refit any plastics that were removed earlier.If there are air leaks you haven’t clamped it into place correctly or you may need that little extra exhaust paste to be applied around the join.