Gasbox

GASBOX CHOPPER FRAMES, EXHAUST SYSTEMS AND PARTS FOR HARLEY-DAVIDSON BUILDS

Gasbox makes a deep catalog of chopper-specific parts centered on full rigid frames, upswept exhaust, oil tanks, and the fabrication hardware to build around them. The coverage spans nearly every Harley-Davidson platform from 1936 through 2022 across Big Twin and Sportster applications. If you are starting a Panhead, Shovelhead, Ironhead, or Evo Sportster chopper from the ground up, Gasbox has the frame, the pipes, the oil tank, and most of what surrounds them.

FULL RIGID CHOPPER FRAMES

The frame is where a Gasbox build starts. Configurations vary by platform, stretch, and tank mount style:

• Big Twin Frames: Full rigid chopper frames for 1936 to 1999 Harley-Davidson Big Twins in 4-speed and 5-speed configurations. Available at standard height or with 3 inches of additional stretch. Tank mount options are Frisco or Sporty. Several configurations include the Gasbox horseshoe oil tank bundled with the frame for builders who want to order everything together. The "Lorain" full frame is an additional Big Twin option at a different specification.

• Ironhead Sportster Frames: Full rigid frames for 1957 to 1985 Ironhead Sportsters. Available with disc brake rear and Sporty tank mounts, with or without the horseshoe oil tank. The "Lorain" full frame is also available for the Ironhead application.

• Evo Sportster Frames: Full rigid chopper frames for 1986 to 2003 Evo Sportsters in multiple configurations: 3 inches up with Frisco or Sporty tank mounts, standard height, with or without the Gasbox horseshoe oil tank. Complete hardware kits for both the Frisco and Sporty tank mount versions are stocked separately for builders who need all fasteners in one order.

• Late Sportster Frames: Full rigid frames for 2004 to 2022 Harley-Davidson Sportsters with Sporty or Frisco tank mounts, available at standard height or 3 inches up.

Browse motorcycle hardtail and motorcycle full frames for the full frame range including Gasbox and Lowbrow Customs hardtail rear sections.

EXHAUST SYSTEMS

Gasbox exhaust is built for rigid and chopper applications where a stock pipe routing does not work:

• Shovelhead Exhaust: The 2-into-1 Cone Shovelhead pipe set is one of the most-reviewed exhaust products in the Gasbox lineup, available in both chrome and bare steel. The hi-lo shotgun set and the upswept rigid application set complete the Shovelhead coverage from 1970 to 1984.

• Panhead Exhaust: Upswept pipe sets for 1948 to 1957 rigid Panheads in chrome, and a broader upswept set covering 1948 to 1965 Panhead rigid applications. Panhead chopper exhaust options are scarce from most suppliers; these sets address that gap directly.

• Sportster Exhaust: Upswept shotgun sets and hi-lo shotgun sets for 1986 to 2003 Evo Sportsters, with specific rigid application versions for choppers where the stock pipe routing will not clear the hardtail section.

Browse the motorcycle exhaust pipes collection for the full Gasbox exhaust range alongside other pipe options.

SISSY BARS, OIL TANKS AND FABRICATION PARTS

• DIY Sissy Bar Kits: The Gasbox Chopper DIY Sissy Bar Kit is one of the most reviewed products in the entire Gasbox range. It gives builders the raw components to build a custom sissy bar to their own dimensions rather than buying a fixed-height chrome unit. The Traveler DIY Kit is a second option with different geometry. Chrome finished sissy bars in pointed, square top, and kick back profiles are also available for builders who want a ready-to-bolt finished piece.

• Oil Tanks: Bolt-on horseshoe oil tanks for rigid Big Twin frames from 1936 to 1957 and for Ironhead Sportster applications from 1952 to 1978. These pair directly with Gasbox rigid frames and with Lowbrow Customs weld-on hardtails.

• Air Cleaners: The Gasbox 007 stainless air cleaner for 1991 to 2022 Harley-Davidson CV carburetors and EFI is among the most-reviewed Gasbox products on the site. The Dog Dish air cleaner covers the same CV/EFI application for builders who want the lower-profile round profile.

• Fabrication and Mounting Parts: Gasbox Sportster top motor mounts with coil and ignition switch mounting provisions, front motor plates for Sportster forward controls, tapered sissy bar and strut rod machined ends, and axle plate threaded bungs for 1936 to 1957 Big Twin rigid frames. Browse motorcycle frame fabrication parts for the complete Gasbox fabrication hardware range.

• Battery Boxes: Universal battery boxes for YTZ-12S and RTX5L-BS batteries, plus an Antigravity 4-cell flat mount box in tumbled aluminum for builders running lithium batteries.