NOTICE:  These are tech pages explaining how I did these mods to my bike.  In almost every case -
I DO NOT SELL THE PARTS DESCRIBED.  I do tell you where I got them.  EXCEPTION - I do sell my custom exhaust mods. 


Tech Tips
Valk Products
My Valkyrie

Fitting TromBones to Stacks for Tourers and Standards




      OK, so you have Mild2WILD TromBone Glasspacks, and you just installed Stainless Stacks.   Now it's hard to operate the TromBone levers.  (Not so with Interstate TromBones, they already work with stacks.) 

      This is the retrofit.  It's pretty easy (with the right tools) a little harder if you have to make do.  I also made a tool to reach the levers so I don't get soot on my gloves, but that's extra. 

      BTW. I think the sound with 4" cut trombones and the stacks is PERFECT.  Try it, you'll like it!


      Nothing if you have the tools.  Less than a buck if you make the lever tool.


      Took me an hour complete including taking these pictures.


    • 1/4" X 16 1/2" hot or cold rolled steel rod for the tool



    • 4 1/2" angle grinder with cutting wheel, or  hack saw and mill bastard file.
    • Propane or acetylene torch (note - MAPP gas - methylacetylene propadiene - looks like a propane cylinder except yellow - with a MAPP gas swirl nozzle burns much hotter than a propane torch - it's poor man's acetylene)
    • small visegrips
    • hammer and anvil
    • bench vise


      Two things we need to ensure happen:  That the TromBones can be latched and unlatched using only the levers (without pushing the other way on the tube),  and that there is clearance for movement of the lever as a handle that can be grabbed easily with a gloved hand or a loop shaped tool.  If yours is an Interstate, you are lucky, your TromBones are already compatible with stacks.

      Some Mild2WILD glasspacks were delivered that require two movements to remove the TromBones - lifting and pulling on the tube while pushing down on the lever.  This was to ensure the tubes were secure and couldn't fall out on the road.  TromBones for Interstates were the exception, since they have extra long levers and you can't reach the tubes.  Later I increased the throw of the latch and the height of the catch for Standards and Tourers too, so the tubes were secure yet they only needed moving the lever to remove them, like the Interstates.

      If your bones require moving the tube up while pushing the lever down, then you need to increase the throw of the latch, and/or reduce the throw required.

      Click on the icon for a bigger pic.  It will open in another window that you can move to the side and continue to read. 

      The handle end of your lever will be folded the opposite way from the lever in the pic.  You need to make it look like the pic.  With your hammer and anvil handy, heat up the bend of the lever "handle" with your torch until it glows cherry red.  Grab it with the small vice grips and bend it towards straight.  Pound it the rest of the way straight with the hammer & anvil.  Now heat it again, and grab it with the vice grips and bend it 90 so it appears as in the picture.

      By the way, you can heat the "spring" if you need to reposition it, if you bought your TromBones after Nov '99.  It is mild, not spring steel, so it's not tempered & won't get brittle.

      To increase the throw of the catch, use the angle grinder with cutter wheel, or the mill bastard file to remove metal at "A".  This allows the latch to move further before contacting the tube.  To reduce the throw needed, remove some metal at "B".  I recommend the former first, then the latter if necessary.  Do it a little at a time and test fit.

      You can also move the glasspack outlet at the catch outward slightly, if needed.  Just use a 3/8" steel drift and hammer, move it a little at a time.  Usually the above metal removal will be enough to get the clearance needed.

      As I mentioned, I made a tool to grab the lever, to keep soot off my gloves.  If you would like to do the same, here's a pic showing scale.  It only took a few minutes to make, you could do the same by heating and bending the end of a large phillips screwdriver.

      Once you're done, you can insert & remove your bones as easy as before you installed the stacks.  And man, WHAT A KILLER SOUND!


All technical mods described here are merely reports of what I've done.  You may attempt to replicate them at your own discretion and risk if you choose.  Horseapple Ranch, LLC and Mark Tobias will in no way be responsible for the results of your attempting to perform these mods on any motorcycle, regardless of the outcome.

All content on copyright 1999-2006 Mark Tobias except "Riders Say", "Dyno Day", Vallejo and Shop Manual and Alternator Review pages, and SWF and MP-3 files and their graphic icons, and any content specifically attributed to another author.  
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