Like I said, I did this on a 400ex, but I dont think it is very different for a z400.
I was looking for a little free power, so I decided to mod a stock exhaust. I asked if anyone wanted to sell one for cheap in the classifieds, and ended up getting one for free.
Getting started
Things you need:
A welder
Something to cut open the exhaust
A hack saw
Drill press
An 8mm socket or wrench
Some high temperature paint
Gloves
Some eye protection.
I used a dremel to cut it open, but a sawsall or hacksaw would probably work better.
First things first
One little tip that will help you out later on is to take a scratch awl or other sharp instrument and scratch some lines in the front of the silencer so you can line it up later. First, unbolt the three 8mm bolts holding on the baffle and clamp the exhaust into a drill press. I drilled 4 ½” holes into the plate inside the exhaust. Another way of doing this is to turn you welder way up and turn the wire feed way down to burn through the metal.
Getting dirty
Now for the hard part. Cut open the exhaust where it angles from the head pipe to the body of the silencer. Once you cut through there will be a pipe inside, and you will need to cut that off too. Once that is cut off you need to remove a 2” section of that pipe.
Getting it all back together.
This is where the scratches come in handy. You can line up the marks so it will be strait when you put it on. I used duct tape to hold it together while I tacked some weld on. After it was sturdy, I put a bead all the way around. When you are welding thin metal, you need to turn your wire feed up to keep the metal cooler; otherwise you will burn through.
Finishing touches
Now it is time to paint. Find a nice dry place to paint. Make sure you use high temp paint so it doesn’t bubble off. I used black, but you could use any color you wanted to match your quad. After the paint has dried, polish up the baffle with some paper towel while it is off. If it is really bad, now would be a good time to get some regular metal polish on it and clean it up good. Bolt that back on and make sure the bolts are good and tight.
Congratulations!
You have just gotten yourself a free aftermarket exhaust that is much quieter then other systems, but still has a better sound then stock. I am not using the exhaust on my quad, but have driven the 400ex that it is on, and it seems to make a noticeable difference in low end power, and sounds much better then stock. It was a very rewarding project, and gives you the ultimate sleeper quad, perfect for sneaking up on unwary 4-wheelers.
I was looking for a little free power, so I decided to mod a stock exhaust. I asked if anyone wanted to sell one for cheap in the classifieds, and ended up getting one for free.
Getting started
Things you need:
A welder
Something to cut open the exhaust
A hack saw
Drill press
An 8mm socket or wrench
Some high temperature paint
Gloves
Some eye protection.
I used a dremel to cut it open, but a sawsall or hacksaw would probably work better.
First things first
One little tip that will help you out later on is to take a scratch awl or other sharp instrument and scratch some lines in the front of the silencer so you can line it up later. First, unbolt the three 8mm bolts holding on the baffle and clamp the exhaust into a drill press. I drilled 4 ½” holes into the plate inside the exhaust. Another way of doing this is to turn you welder way up and turn the wire feed way down to burn through the metal.
Getting dirty
Now for the hard part. Cut open the exhaust where it angles from the head pipe to the body of the silencer. Once you cut through there will be a pipe inside, and you will need to cut that off too. Once that is cut off you need to remove a 2” section of that pipe.
Getting it all back together.
This is where the scratches come in handy. You can line up the marks so it will be strait when you put it on. I used duct tape to hold it together while I tacked some weld on. After it was sturdy, I put a bead all the way around. When you are welding thin metal, you need to turn your wire feed up to keep the metal cooler; otherwise you will burn through.
Finishing touches
Now it is time to paint. Find a nice dry place to paint. Make sure you use high temp paint so it doesn’t bubble off. I used black, but you could use any color you wanted to match your quad. After the paint has dried, polish up the baffle with some paper towel while it is off. If it is really bad, now would be a good time to get some regular metal polish on it and clean it up good. Bolt that back on and make sure the bolts are good and tight.
Congratulations!
You have just gotten yourself a free aftermarket exhaust that is much quieter then other systems, but still has a better sound then stock. I am not using the exhaust on my quad, but have driven the 400ex that it is on, and it seems to make a noticeable difference in low end power, and sounds much better then stock. It was a very rewarding project, and gives you the ultimate sleeper quad, perfect for sneaking up on unwary 4-wheelers.