Stock headers / aftermarket Mufflers

pamcopete · Posted: May 27, 2009, 5:45 pm Post subject: Stock headers / aftermarket Mufflers

The stock headers are double walled, meaning that the "real" exhaust pipe is inside an outer pipe that is not supposed to carry any exhaust. People make the mistake of just clamping an aftermarket muffler to the outer pipe. The outer pipe has a couple of vent holes and it is not pressure proof welded to the flange that "plugs" into the exhaust port, so the whole deal leaks like crazy.

Here is a pic of the inner pipe.

Here is a possible solution that I use on my '81/H with stock headers and aftermarket mufflers.

First, go to your local auto supply store and buy a couple of these adapters:

The part number is 548520. They are a 1 1/2 ID to 1 3/8 OD adapter.

Clamp the muffler to the larger end of the adapter:

Insert the muffler with the adapter over the inner pipe:

The fit is very tight, but you can also use some muffler sealer to ensure a leak proof fit, or just wait a few days for the accumulaiton of carbon to do the job for you.

xs1961

Thats good ..
Are there still stock downpipes out there...?

Everything_To_Xs

Yea my 81 has stock pipes

borjawil

what if the inner tube is removed? would it make difference?

What Happened to 650rider.com?

Yamaha xs650