THRASHIN Anti-Reversion Exhaust System - M8 Softail

  • $1,445.99
    Unit price per 
Tax included.

Please allow 7-10 business days for Show Polish Finish.

For Black Ceramic Finish please allow 2-3 weeks until exhaust is shipped.

Exhaust systems ARE NOT LEGAL FOR SALE OR USE IN CALIFORNIA ON ANY POLLUTION CONTROLLED MOTOR VEHICLES. The following disclaimer is associated with these THRASHIN products.

DISCLAIMER: We will not ship any exhaust with a California shipping address, our order will be refunded immediately. 

We have teamed up with Feuling® Parts to bring you the ultimate in V-Twin Performance Exhaust. Over a year in the making and countless hours spent on design and in the Dyno room, we bring you the all new THRASHIN® Anti-Reversion™ Exhaust system!

The Thrashin® 2>1 Anti-Reversion™ Exhaust system has equalength stepped headpipes with Jim Feuling's patented design anti-reversion™ 'AR' chambers™ (Patent # US 4206600 A & 6336471 B1), transition merge collector (Patent # 4,796,426) and optional perforated 'dog ball' muffler core (Patent #5,173,576). These technologies promote continuous exhaust gas flow, reducing 'reversionary' pressure waves or 'unwanted' exhaust pollution of the intake charge and combustion chamber, providing increased engine performance and efficiency.

This true performance stainless steel pipe starts with square cut headpipe spigots which promote a smooth transition from the exhaust port to headpipe with a true .625" inside diameter. Eliminating the choked up transition and mushroomed gaskets common with most exhaust systems.

Jim Feuling's patented headpipe AR Chambers® are placed at the transition from 1 3/4" to 1 7/8". Our performance merge collector has a exit AR Chamber™ into the 2 1/2" muffler inlet. The optional 'Dog Ball' baffle absorbs high pitch frequencies, producing a unique deep tone while minimizing the effects to column inertia through the muffler. All Thrashin® baffles are wrapped in replaceable stainless steel wool and high temperature fiberglass, providing extended life packing while minimizing muffler discoloration. The exhaust exit is capped off with optional styles of reverse end cones and ID sizing to meet your engines demands and personal sound preference.

These combined features reduce gas flow resistance, back pressure and aid in the elimination of reversionary effect. DESIGNED AND MADE IN AMERICA.

Thrashin® recommends using square cut or crush ring exhaust gaskets and having your motorcycle properly tuned for best overall performance and pipe longevity.

18mm o2 sensors with 12mm reducers. Bungs are in place to work with stock o2 sensors. If aftermarket sensors are used, you may need to relocate bung.*


2 1/4" stepped to 2 1/2" perforated Feuling 'Dog Ball' baffle Part # TSC-1960-0
Designed for smaller cubic inch performance engines, the 2 1/4" inlet delivers good low end torque and the step up to 2.5 allows the engine to breathe at higher RPM. This baffle has an aggressive crisp and snappy sound with the signature 'Dog Ball' higher RPM note.

2 1/4" straight through perforated core Part # TSC-1951-0
Best suited for mild performance and or larger cubic inch engines looking for higher RPM power and or a louder more aggressive sound. This core out flows the 2 1/4 Dog Ball baffle. Smaller engines may sacrifice some low end throttle response.

2 1/2" stepped to 2 3/4“ perforated Feuling 'Dog Ball' baffle Part # TSC-1961-0
Designed for larger cubic inch high performance engines, this baffle has a 2 1/2” inlet stepped to 2 3/4”. This is a high flow baffle that produces superior low/mid range torque without sacrificing top end power. Aggressive crisp and snappy sound with the signature 'Dog Ball' higher RPM note.

2 1/2" straight through perforated core Part # TSC-1952-0 
Designed for high performance and larger cubic inch engines looking for a very aggressive sound.


2 options of our end caps to choose from. 

1.) Tapered style End Cap #TSC-1211

2.) Standard Cone style End Cap #TSC-1210