db killer removal
 

Yamaha XT660Z Akrapovic Exhausts have Catalytic Converters. No need to remove cans... I've used a leatherman to remove the db killers once you've removed the allen screws.

removing DB killers on Akras
 

If you're worried about scratching, I put some insulating tape around end of baffles and pulled/twist with a set of pump pliers.
You won't want to put them back in though!

I've tried to find some kind of description of how to remove the db killers from the Akra pipes. I just mounted them and I'd like to try them without the db killers. However, there's nothing mentioned about it in the mounting instructions I got with the pipes and after searching a bit on Google as well as this forum I haven't found anything. You're mentioning "the Allen bolts".....what Allen bolts? Where are they? Under the heat shield? Starting to feel like everyone else thinks this is obvious and I'm just plain stupid...

The Allen bolt(s) are hidden behind a small rubber gromit on the underside of the cone shaped end, just pop the gromit out to reveil them. Their a bit fiddily to get back in, the hole in the exhaust must line up perfectly with the threaded hole in the DB killer.
Hope this helps , sorry I haven't posted a pic but I've just got home at 2.30am.

Ah, ok, I was actually thinking that may be a possibility but I hadn't looked into it yet. Thanks for the tip. I'll give it a try this weekend. :-)

I know some people have had problems getting the db killers out but I had no problems at all. It can't have been much more than a five minute operation from removing the rubber gromit to access the allen bolts to having them back in place. Surprisingly the entire operation went very smooth. The bike is certainly much louder but the air pressure out of the system is also much higher indicating a far better air flow. I don't have time to go for a test ride this weekend but I'm looking forward to doing it next weekend.