🚚 Free Canada-wide shipping on orders over $199 (excluding oversized items)
TC Bros steel weld-in petcock bungs are essential components for custom motorcycle fuel tank and oil tank fabrication. These precision-manufactured NPT (National Pipe Thread) bungs provide secure, leak-proof mounting points for petcocks and tank fittings. Available in 1/4" and 3/8" NPT sizes to accommodate different petcock and fitting requirements.
1/4" NPT: The 1/4" NPT size is the most common size for motorcycle fuel tank petcocks and oil tank fittings. This size works with standard petcocks and provides adequate flow for most applications. If you're replacing an existing petcock or using a standard aftermarket petcock, 1/4" NPT is likely the correct size.
3/8" NPT: The 3/8" NPT size offers a larger opening for higher flow applications or when using specific fittings that require the larger thread size. This size is ideal for custom applications, larger displacement engines, or when maximum fuel flow is desired. Always verify your petcock or fitting thread size before ordering.
NPT (National Pipe Thread) threads are tapered, meaning the diameter gradually decreases along the length of the threads. This tapered design is critical for creating a leak-proof seal. As you tighten an NPT fitting into an NPT bung, the tapered threads wedge together, creating a tight, sealed connection.
Important: NPT threads are ONLY designed to be used with corresponding NPT threaded fittings or pipe. Do not attempt to use standard bolts, machine screws, or non-NPT hardware with these bungs, as they will not seal properly and may leak.
Proper installation is critical for leak-free performance:
Safety Warning: Welding on fuel tanks is extremely dangerous if not done properly. Fuel vapors can ignite or explode. Only qualified professionals should weld on fuel tanks. Always follow proper safety procedures including complete fuel drainage, tank purging, and ventilation.
Each pair of TC Bros steel weld-in petcock bungs is precision-manufactured from premium American 1018 cold rolled steel to ensure reliable welding, proper thread engagement, and leak-free performance for your custom motorcycle fuel or oil tank.
TC Bros Universal Frisco Gas Tank Mounting Kit - Stainless Hardware with Tophat Bungs
Regular price $56.95🚚 Free Canada-wide shipping on orders over $199 (excluding oversized items)
Mount your gas tank with confidence using this complete Frisco-style mounting kit. Everything you need for a professional, secure installation on custom choppers and bobbers.
This mounting kit is ideal for custom motorcycle builders working on choppers, bobbers, and cafe racers. The Frisco-style mounting system is a time-tested solution that provides secure tank attachment while maintaining the clean lines of a custom build.
Installation Note: Tophat bungs require welding to the frame. Ensure proper fitment and alignment before welding.
TC Bros.-Leather Cushion Washers with 3/8 inch Hole 10 pack
Regular price $13.95🚚 Free Canada-wide shipping on orders over $199 (excluding oversized items)
These leather washers are perfect for protecting your paint and are more durable than rubber. The cushioning & dampening effect that these washers provide is perfect for installing between your frame and mounting tabs found on gas tanks, fenders, oil tanks, or anything else you want to protect from vibration. Also great for use under solo seat springs to prevent squeaking. Dimensions are 1 inch diameter x 3/8 inch hole x 1/8 inch thick. Sold in pack of 10 washers.
TC Bros - Weld On Solo Seat Mount
Regular price $77.95🚚 Free Canada-wide shipping on orders over $199 (excluding oversized items)
Transform your bobber or chopper build with TC Bros' precision-engineered Weld On Solo Seat Spring Mounts. These CNC-machined mounts deliver the rock-solid foundation your custom seat deserves, combining old-school craftsmanship with modern manufacturing precision.
Imagine the satisfaction of a perfectly mounted solo seat that moves with you on every ride—no rattles, no flex, just smooth suspension action from your torsion springs. These aren't stamped sheet metal brackets that'll fail after a season. They're machined from solid 1018 cold rolled steel, built to handle years of hard riding.
Note: Seat springs sold separately
The pre-coped radius means these mounts sit flush against your frame tube right out of the box. Position them where you want your seat, tack them in place, check your alignment, then lay down a solid bead. The universal design gives you complete freedom to position your seat exactly where it feels right for your build.
TC Bros understands what custom motorcycle fabricators need because they're fabricators themselves. These mounts represent the same quality and attention to detail you'll find throughout their entire line of chopper and bobber components.
Ready to mount your custom seat the right way? Add these professional-grade spring mounts to your cart and take the next step in your build.
TC Bros Threaded Steel Bungs - Standard (5/16-18 & 3/8-16)
Regular price $27.95🚚 Free Canada-wide shipping on orders over $199 (excluding oversized items)
TC Bros standard threaded steel bungs are essential fabrication components for custom motorcycle builds. These precision-manufactured bungs provide secure, threaded mounting points for gas tanks, seat pans, fenders, battery boxes, and countless other components. Available in two thread sizes and three lengths to accommodate various mounting applications.
Thread Sizes: 5/16-18 or 3/8-16
Lengths: 1/2", 1", or 1.5"
Depending on your specific application, you might need a different style of bung or mounting solution:
Alternative Bung Styles:
Non-Threaded Mounting Solutions:
These bungs are designed to be welded onto your motorcycle frame, gas tank, fenders, or other components at the desired mounting location. Proper positioning and alignment are critical for correct fitment and function. We recommend:
Professional installation is recommended if you're not experienced with welding and frame fabrication. Each TC Bros steel bung is precision-manufactured to exacting standards for reliable performance on your custom motorcycle build.
TC Bros Universal Fender Strut Kit
Regular price $87.95🚚 Free Canada-wide shipping on orders over $199 (excluding oversized items)
Kit includes:
(4) CNC Machined steel bungs with 3/8-16 threaded hole
(2) 12" long 1/2" diameter steel rods.
Everything is made in USA from 1018 mild steel for easy welding.
For some extra style, use the TC Bros Mounting Bung Kit