View Full Version : Supertrapp internal discs for 2011 FLHX - starting Disc configuration

09-13-2011, 09:02 PM
Hi All,

I'm looking to purchase the internal disc series 628-78055 for my 2011 streetglide FLHX. My question is what is a good starting configuration for discs in these pipes??

I'm looking for more torque and a little louder than stock, but not a huge amount - as opposed to increasing horsepower. The mods I've done on the bike to date are a high flow air kit, a 255 SE cam and race tuned the engine. Current pipes are stock.

In so far as the research I've done to date, I've read the installation instructions for this model, but there wasn't a recommended starting configuturation. I've also checked the HD forums and there are various disc configurations, but most seem to optimise power, and loudness - not torque. Also some seem contractictory - some recommending the same number of discs per pipe - others recommending more discs in the right hand pipe.

Any recommendations on this would be really cool and thanks for your help in advance, Hamish

09-14-2011, 07:14 AM
For the '09 (and later) model HD touring bikes the headpipe design changed and exhaust flow is comparable to both sides. Prior to '09 the headpipe favored the right side and in most cases unequal amount of discs could be beneficial.
The 12 discs supplied (each side) should be a good starting point for the performance you are looking for.

09-15-2011, 04:32 PM
thanks heaps - will go ahead and purchase now, cheers, H

09-29-2011, 03:46 PM
Hi All,

I now have these pipes and love them - am finding them a bit loud though. What is the minimum discs I can have in per side and still get good performance without choking the engine??

Many Thanks, H

09-30-2011, 08:35 AM
6-8 discs would be the least you would want to run (per muffler).