Hey guys, I must say I think that the best money I have ever spent or charged (ha ha) is on my 01' 426. I am pondering on buying the r-4 slip-on vs. just keeping the bike stock. My bike absolutely ripps (5th gear wheelies downhill), just wondering if anyone has this slipon with the stock headpipe and have left jetting stock. I have posted a similiar topic on this muffler but would just like a little more info before I drop the $175. How about sound increase or power gains. As far as I am concerned the louder the better. I would prefer to just install it and leave everything else stock. any info is greatly appreciated, Thanks!! Any cheaper anywhere than $175.00 Live to ride....Ride to Live!!