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Canuck20
08-21-2008, 06:10 PM
Fantastic idea to develop this forum! Was hoping to get your insight on the following for my 2004 Harley Superglide (S.E. air cleaner, Power Commander).

I tried a set of your 3-inch internal-disc slip-ons and really liked the way they performed. However, when moderate-to-hard cornering to the right, I would scrape the endcap bolt on the lower muffler (probably because the muffler diameter is larger than the stock ones). I replaced the bolt a few times but didn't want to end up scraping the actual muffler body so went with a Kerker 2 into 1, which gives me more ground clearance. Besides, I like the look of a 2 into 1.

The Kerker is awesome in terms of fit and finish and I think it really allows the motor to open-up. Runs GREAT with the MAP supplied by Power Commander. In the interests of neighbour relations, I'm looking for a way to quieten the sound of this straight-through muffler. I've got another 4-inch series Supertrapp muffler but the mount is not in the correct spot for proper alignment on my bike. I've tried to exchange the two baffles but the Supertrapp is about 2 inches too long to fit in the Kerker muffler.

Any foreseeable problems with shortening the Supertrapp baffle to fit the Kerker muffler? Also, the Supertrapp baffle seems very restrictive even with no discs or end cap - is this typical? Conceivably, I could drill some of the baffle and tune for sound with the discs and endcap and then dyno tune for mixture/rideability, but is that rational?

Again, thanks for introducing this forum. I would appreciate all input you can offer.

bschultz
08-22-2008, 07:19 AM
Riders/tuners are experimenting/altering their components all the time. The main concern of swapping an altered core is proper fitment and flow characteristics. The back of the core assembly can be secured with screws; however the inlet end of the core needs to be sized to the muffler body to be centered and secure.
Our current SuperMeg 2:1's (SuperTrapp & Kerker) both run 2.5" cores, so I'm not sure what SuperTrapp muffler you have, (to make it seem more restrictive). The 2:1 systems use the same headpipes, so you could swap out the whole muffler assembly.

Canuck20
09-07-2008, 01:52 PM
Thanks for your reply. The Kerker muffler is numbered 027 7142 while the Supertrapp is 027 7492. I'm sorry I didn't supply the muffler model numbers earlier but does it make sense that this Supertrapp muffler seems somewhat restrictive?

Instead of shortening the Supertrapp baffle, I'm planning on fabricating an adapter bracket that'll allow me to rotate the muffler for better outlet alignment. Are there any freer-flowing baffles available for this Supertrapp muffler. Are there any other baffles available for the Kerker muffler that aren't as loud?

Have any other slip-on users reported scraping the muffler while cornering (my 2004 Super Glide suspension isn't lowered)?

Sorry for all the questions and thanks again for all your help.

bschultz
09-08-2008, 07:38 AM
Again, both the SuperTrapp and Kerker run 2.5" cores, the same size as the collector. The only restiction will be the amount of discs used.
The core assemblies used in our XR750 race systems are larger/freer flowing; however would need further modification to use in the megaphone body for the dressers.
Nothing quieter for the Kerker.
We have had an ocassional report of an aggressive rider report scraping while cornering.

Canuck20
09-11-2008, 01:11 PM
Thanks for your reply, much appreciated. I'll do some experimentation with the various mufflers and baffles the next few months and try to post some results.