Hey guys,

I've got a new S40 that I've added a slip on HD Dyna muffler to.   The bike runs really well, but I think that the mixture is too lean as it seems to bog in the lower RPM range.  I also have some backfiring when I ease off the throttle.  

Can someone give me a step by step (I have no experience with carbs but am very good with my hands) rendition of the fix for rejetting?  Also, will this void my warranty for bike?  I can remove the bolt on HD muffler fairly easy if I need to take it in, but will the carb changes void it?

Thanks!!

So, in your opinion, would you replace the HD with the stock muffler until the warranty is out and I can make the needed carb adjustments?  The bike runs pretty good and sounds better, but I think the performance was a tad better with the stock.  

Thanks again!!

I ride the bike everyday, almost.  It's due the 600 mile service, actually.  Before I installed the HD muffler, it would backfire almost every time the bike is shut off, but with it, it sputters a little during deceleration, but not at shut off.  

Anyway, I definately like the way the HD looks and sounds as apposed to the stock muffler, but I don't want to take anything away from the way the bike performs.

I'd keep the HD muffler and even rejet. I understand it won't void warranty unless your bike has an issue directly related to the mods. Rejet when you get a chance - it makes a big difference in performance. It should stop most of the popping too.