Glasspack mod help

[freeindeed]

I'm new to this forum as I'm new to the Valkyrie. This summer, a 97 Bumblebee Standard found me. The best bike I'v ever owned. As the title says, I need some help from guys who have done this glasspack mod. It would be nice to pay someone like Mark T to make a set for me but I just cant swing it. I have the tools and can weld (but I'm not a welder by trade, I'm a mechanic) Besides that, I need a fun winter project.
So the stock pipes have the piggies cut back and and nothing is drilled. I would really like the bike to be a little louder than it is. The glasspacks, I think are the answer for me. I'm 63 and have hearing issues too. But I've heard this engine can really talk with pipes done right. I can't do the really loud exhaust. I have another set of unmodified pipes so if I ever want to shut it up I can. Or if NY ever starts enforcing stock only exhaust.
 I'm a little unsure of where to go from here. I have done what I thought was an extensive search on this forum and I think I think I have a fair understanding on the subject, but still lacking for sure. So I apologize in advance for any perceived dumb questions. I'm thinking I would go with stainless or chrome 4" truck stacks. Other than appearance, would it matter? I like the idea of making baffles out of the rest of it to add later to install in the ends of the stack, if needed. I have a lathe that I can do the "skinning" work, that soon to be retired Mark T. talks about.

1) Chosing the glasspacks to keep backpressure and current horsepower are where I'm not sure. Specifically the dimentions. Someone mentioned a core of 1.5 inches, in and out. I can't find them. Is that critical? What really is  recomended? Are 2" acceptable? A deep tone at idle is what I'm hoping for.

2) 18" in length sounds like many have pointed out. Longer? Shorter? I don't  want to thread anything for swapping out for different tones, like I've read about in another variant

3) The body size of the glasspack has me a little confused. So if I choose a glasspack with a 4" O.D. and pipe @ 4" I.D. The welds need to be damn straight to slide over that, then over about 7" of collector pipe right? Doesn't sound like theres any room for error. But if I know that going in, I should be able to keep everything straight and slip the stack on without beating it on.

4)   If I use, say a 3.5 " glasspack body on a 4" stack, what do you use to attach and seal the gap between the glasspack
    body and the stack before it exits out the tube?

5) Making the transition from the collector to the glasspack. Should that be tapered/funneled?

6) Mounting studs. Make the 2"x9" cut on the backside and weld on bolts or studs for the brackets. correct?

    I may not be asking all the correct questions and perhaps some wrong ones but I simply want to get it as right as I can
    the first time around         

   Additionally,  you may be thinking, I'm missing some conceps or ideas here, you could be right. So if they're explained
   somewhere else, maybe you could direct me to them.

      Thanks in advance
       Merry Christmas.  Rob

[WintrSol]

I'd start by reading the file in Shoptalk: http://www.valkyrieriders.com/shoptalk/easymod.htm
There are more in Shoptalk: http://www.valkyrieriders.com/shoptalk/

[Joe333x]

I'm in a very similar situation as you and what I am going to do to keep things simple is cut about 7~ inches off the back if the muffler, maybe drill out the baffles on the remaining ones in the muffler. Then turn the part cut off into a silencer for the end like you said. Not going to bother with a glass pack, if I want it quiet, Ill stick the silencer in and if I want it loud, I'll take it out.

[WintrSol]

A previous owner installed glass packs in my Tourer, and, while I liked the sound, they were just a bit loud for me. So, I used caps for natural gas pipes to make 'lollipops' to partially block the exits. If it had been too much, I could have taken them out, ground them a bit smaller, and put them back it. I did the same with the pipes on my Intruder, and went through three sets to find the sound I wanted.

[Itinifni]

As WintrSol mentioned there is good information in the shoptalk section.

Rather than making your own baffles and if you go with 4" truck stacks google 4" marine silencer, there are lots of options out there ready made. I haven't used them but I think quite a few have with good results.

https://www.hardin-marine.com/p-12622-4-slip-in-silencer.aspx

I had Mark T make my exhaust, exactly what I wanted.

Good luck!

[WintrSol]

Those would be great; my packs have outlets a bit over 2", unfortunately. I couldn't find silencers that small, but I admit I didn't try very hard, as I had already made several sets already, and I knew I could customize them with a grinder or a drill.