Carbon cleaner / remover for exhaust components

[kd]

I have 2 exhaust systems for my 2011 RGU 120 (Dragula one 2.55 baffle and the other is a Burns 3.0" baffle).  The Burns is loud enough to cause physical pain to your ears (the way I ride  ) and also attracts a lot of un-needed attention.   As expected, the Burns outperforms the Dragula with the exception of the 2500 to 3500 rpm area. At 2500 it leaves approximately 15# of torque on the table. I built an exhaust stinger capable of running 4" SuperTrapp discs to tame the Burns volume and hopefully reduce the loss of torque in  that range but keep the rest. It needs to hit the dyno again to test.

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I opted to use the tune for the 2.55" baffle Dragula 1 pipe because I was adding restriction to the 3" Burns.  The fixture is at this point using 48 discs with a closed endcap.  It did what I hoped with the sound volume but it is running fat like this.  It starts to accumulate soot in the discs after a few hundred miles so I am adding more. 

I pulled it apart yesterday to clean to add a few more discs (or washers).  The carbon was stuck to the discs real bad and took a lot of work with a drill and wire brush to clean.  My concern is that the gap between the discs is very tight and it needs to stay clean.   I tried brake cleaner, carb and choke cleaner and varsol but the drill was what worked the best. It took a while and I have realized I need to find a better way. 

I am wondering if anyone has any experience keeping a SuperTrapp style disc stack clean without all of the work I went through disassembling and scrubbing.  I am looking for a way to possibly spray clean with a proper solvent between the discs when I am washing the bike.  I hope once it is tuned to the discs it will fun cleaner but I am all ears looking for an easier way for at least right now while I am setting the disc count. 

 

[harpwrench]

I think you'd be better off using the calibration for the burns pipe, and add discs until it feels like it's working right. You're adding discs to hopefully flow as much as the baffle. Also with that many discs, and especially with washers, I've found it isn't any quieter than using the open end cap, or even enlargening the hole in one. It makes no sense to use a cal with different primary lengths diameters and baffle. I just spray mine with carb cleaner once a year maybe, just because, but when it's right all there is is a smoky gray film.

[kd]

I think you'd be better off using the calibration for the burns pipe, and add discs until it feels like it's working right. You're adding discs to hopefully flow as much as the baffle. Also with that many discs, and especially with washers, I've found it isn't any quieter than using the open end cap, or even enlargening the hole in one. It makes no sense to use a cal with different primary lengths diameters and baffle. I just spray mine with carb cleaner once a year maybe, just because, but when it's right all there is is a smoky gray film.

Thanks for that.  I was actually thinking that may be the best but I had been running the Dragula around town to keep the heat (LEO) away.  I changed the pipe when I got the fixture machining completed and figured the difference between the 2.55" and 3" baffle it would make sense.  My Burns was actually the first one (prototype) made and I asked for 8" longer primaries.  The muffler actually ends even with the back radius of the rear wheel rim. 


Because I have it ready to go back on, I'll probably try a few more discs and space the ones behind the heat shield (maybe 3) with #10 lock washers.  Then, as you say, I'll have to change tunes and see how it works out.  I also have an open end cap to try.  I did have it on previously but it didn't do well at masking the volume.  I was actually saving that part for when I can arrange to get on a dyno with someone I trust to do a good job but I may give it another go.  My problem is I and at least a day away from a good tuner plus overnighting etc, so I want to have tried some options to start with.

 

[kd]

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