RK mufflers

[dlhoulton]

I've been following and reading some posts on installing RK slip-ons. Have also read how to mod them for more sound. Everyone talks about drilling out, knocking out plugs, etc. Today I found a local customizing shop for Harley's and asked if he had any RKs. He took me over to a shelf he had in back and got several down to show me. One set were stright tip and I could not see through them another set which he had cut out (gutted) were in bad shape. Then he showed me what he said was a newer set (he said from an 06) that were slash cut style and were in good shape. When I held them up I could see all the way through them no plugs or anything blocking view or anything. I could see a pipe in the center with lots of holes in it running the length of the inner pipe.

He said they were stock and nothing had been done to them. My question is are there diff cores in the stock RK mufflers. Some blocked by plugs and baffles and some that you can see stright through? Sure need help.

[Squidley]

Dennis,

If you could see right through them they aren stock as someone has already removed the 2 baffle plates in them. I would actually get that set of slash cut ones if they are like that and in good shape as your work would be done. You also have a PM

[dlhoulton]

I went ahead and got the slashed cut (slash up) set. The slash will match the angle of the saddlebags. When I look in on the outlet end they are clean, no rust and show no sign of cutting. Look just like RSV pipes only slashed insted of stright. When I look inside the inlet side I can see inside about three to four inches to a donut plate that holds the inner pipe. The donut has a series of 1/4" (more or less) holes in it (one at one o'clock, one at four, one at five, one at seven and two side by side at ten o'clock) which all look stock. Don't see any sign of cutting, drilling or knocking out of any plugs or plates!!! No rust or anything. That's why I'm confused when they say they drill, use a rod to knock out plugs/baffle plates!!! These came stright off a HD and would not have had the need for modification for an HD rider. Still like I described, you can see stright through the inner pipe (which is lined with holes). Do you think these have been modified or are they a stock pair of RK's. The shop that I got them from only works on custom Harley's. If in your opinion they have been modified what phase or level would they be in. And how loud will they be??

[royalstarjac]

Sounds like they're already drilled out. put em on and see how they sound. If you want em louder drill em out some more.