Hey y'all.

Recently bought a 2006 DS 650x from a guy. Solid tight bike, price was good, blahblah. Completely stock, except the pipe, gutted factory pipe. Its loud and noisy, but thats fine. My problem is it seems to lack power. It comes on good and smooth through the whole RPM range, but just doesnt seem as strong as it should. Since this is my first DS to ride, i have nothing to compare it to, aside from it just barely will beat a predator in a straight line. I've had friends ride it and all, they say the same thing, nice tight bike and fast, just not as fast/quick as we would have expected. All the obvious things are fine, plugs, oil, air filter, etc. all the easy stuff is fine..

Anyone else had this issue? IDK if i need to re-jet or what. I dont mind the extra noise, and i dont wanna buy a $400 pipe.

 

When you say the muffler is gutted, are you sure that the metal inside the muffler has been cut out, or is it just missing the packing material? Is the spark arrestor on the endcap intact as well? If the muffler is gutted of metal and packing material, I would expect that you would need to jet up from a stock 165 to a 170 or possibly 175 depending....

The DS muffler should have some pretty good flow rates becuase of how large it is, it is the restrictive end cap that is the killer.

Alternatives to a new muffler would be get a aftermarket end cap ($80), and put the packing material back into the muffler to save your sanity and hearing. I believe the common billet endcap you will find out there has a spark arrestor screen on it, but I don't believe it will pass the forest service DB or spark arrestor test. You can get fined if you get caught.

I cheaped out and made my own end cap from a FMF cap I found on the net. http://forums.atvconnection.com/3080538-post1.html I went this route because I know that in the areas I ride the forest service will stop you and check for an approved spark arrestor, and I don't want to have to deal with fines. I have been stoped and checked before, and nothing was said about the loudness, but for sure they were interested in the spark arrestor.

 

Another thing to check, is the rubber diaphram on top of the carburetor.. If it gets even a tiny hole in it, it will run really rich, and lack power. A compression test would be a good idea, too.