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1.  Let me first start with the fact that I am NOT a mechanic.  I have been working on motorcycles and scooters for a long time and know a little about what I am doing.  I simply take pictures for other people to use as a guideline to help them modify their own motors.  Any modifications you perform are done completely at your own risk and liability.

2.  Tampering with your motor in any way may void your warranty.  Make sure this is a sacrifice you are willing to make before you begin working on your own vehicle.

3.  Before you begin, read this ENTIRE article from start to finish so you know exactly what is involved and what steps are required to properly complete the procedure.  Also make sure you have a nice clean area to work in.

4.  This example was performed on a 2006 Sachs MadAss 50cc automatic.

5.  ALL bolts and socket head cap screws are in metric! Don't try to work on your vehicle if you don't have metric tools, you will just wind up messing up the heads.

The OEM exhaust on the MadAss is really a nice looking exhaust.  Unfortunately, it is also very restrictive.  Small inner diameter coupled with the muffler characteristics, it is robbing your bike of some serious power.  Factor in a larger displacement engine like our 150cc Lifan, and this exhaust simply will not do.  So we scoured the internet for a replacement.  At the time of ordering, there was simply only one option available.  The ASS PIPE available through Moto-Scoot.
Now I must say, for being the only pipe available, I am very pleased with the style, sound and performance.  The very deep growl sound of this exhaust definitely gets some heads turning.  Not to mention the large ID on this thing, it simply lets the air our out of it!
Start by removing the flange off the stock pipe.
Next remove the attachment springs and the bolt under the seat.
Slide the pipe out of the muffler and remove it.
Now, you are stuck with the muffler and your tail lamp and turn signals hanging out there all by themselves.  We eventually made a custom tail lamp / turn signal unit for our bike, but for temporary purposes, we unbolted the tail lamp assembly from the muffler and then removed it.  We then disconnected all the wiring from the tail lamp assembly under the seat so we could remove the small pipe that the wires run in around the muffler.  Once the pipe was removed, we bolted the entire tail lamp assembly to where the exhaust was mounted
We had to add a nut and some washers in between the mounting bracket and the tail lamp assembly.
It isn't the most glamorous thing, but is very functional, and doesn't look all that bad.  Tuck the extra wire length up under the seat and zip tie everything back into place.
Now our new Ass Pipe is attached where the brake pedal is mounted.  So we had to remove the bolt holding the brake pedal in place.  Slide the bolt into the pipes bracket and replace the bolt.
Place your exhaust gasket on the pipe and slid it up into the motors recessed hole.  Place the flange over the bolts and tighten them up.  We had to make a few minor adjustments to the pipe as we were tightening things up to get the pipe in close to the motor as we could while keeping plenty of clearance for the brake lever.

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