The Factory 4.1 system will give you a noticeable increase in all around power, and also shed some weight from your machine. Superior power on stock and big bore motors and the centralized mass improves handling. FMF takes fun seriously, so they built the Mini Factory 4.1. This is an all out performance exhaust for play bikes. With the Mini Factory 4.1, you will be the king of backyard motocross and look great doing it! The lightest available. Superior power on stock and big bore motors. Patented Chamber Core for optimum performance. Engineered for compactness and centralized mass. Exclusive mounting design. Easily serviced for re-packing. Customize with tuning inserts and spark arrestor. Detailed Specifications: Type: System. Construction: Titanium. Finish: Natural. Midpipe: Stainless steel. Spark arrestor: insert (sold separately). Quiet insert: Quiet insert (sold separately). Header Construction: Stainless steel. Header type: Hi-Flo. Weight: 3.5 pounds. Note: For closed course competition use only. Not intended for street use.
The Pro Circuit R304 Shorty End Cap Silencer features 304 stainless steel end caps and intake tube. Extruded 6061 T-6 aluminum short housing with brushed finish. Lightweight, with high strength steel rivets and steel Allen head screws on 1 end for easy disassembly and rebuilding. The Pro Circuit 304 Factory Sound End Cap Silencer is constructed from the same materials as the Shorty End Cap Silencer. Longer aluminum housing for added top end performance. TIG & MIG welded for added strength & durability. Pro Circuit Pipes are tuned specifically for the year & make of the bike to achieve a performance gain in the areas that your stock pipe is lacking. Pro Circuit does not produce many different pipes for a single model bike, they make one pipe that performs well in all power ranges. The only difference between the Platinum & the Works pipe is the finish.