Modify XR650L stock exhaust

I have a 2007 XR650L. I have removed the snorkel, gone to a UNI filter, switched to a 14T front sprocket and i am in the process of jetting to a 55/158, but before I do that I would like to know if I can modify my stock exhaust. I am not ready to lay out the cash yet for an after market system.:worthy:

If you cut the weld and pull the bolts at the outlet, you can pull the insert. That gains a little snap.

It was a little too loud (and oddly 'boomy') for me that way.

A sweet mod is to do that, and fab a turndown to direct the noise down.

Dave

when i had my stock exhaust i did that too. i did help, but no more spark arrestor and it did sound sort of weird.

when i had my stock exhaust i did that too. i did help, but no more spark arrestor and it did sound sort of weird.

I'm pretty sure the insert is not the spark arrestor- its made like a glasspack muffler, a straight tube surrounded with fiberglass.

Dave

You can also grind the weld down inside head pipe where it bolts to the head,just don't go over flush inside the pipe.

I'm pretty sure the insert is not the spark arrestor- its made like a glasspack muffler, a straight tube surrounded with fiberglass.

Dave

i only meant that the tube you pull out combined with the packing is a complete unit(being the arrestor). if the tube is gone the whole unit is not functioning as the design was made to be.

i only meant that the tube you pull out combined with the packing is a complete unit(being the arrestor). if the tube is gone the whole unit is not functioning as the design was made to be.

Its been awhile since I've had mine out, but I don't think the outside of the tube you pull is poart of the 'revese flow' section of that type of arrestor.

Only looked down there once, though, and I didn't think the removable ports for cleaning the carbon out went to around the tube.

Dave

you may be right but the removable core sure looks like it has something to do with the"arresting of the spark":busted:

As far as I know the spark arrestor works by sending the sparks into contact with the pipe walls,thats why you remove the two bolts under the pipe,plug the exhaust with a rag and rev the engine to blow out the carbon deposits.How its achieved I don't remember well,it may be by creating a vortex or turbulence.Not sure if removing the packing will alter this.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now