Inline Spring Fork Assembly 18″ Chrome – Fitment Checked
Consistent Chrome Finish — Every 18″ inline spring fork assembly is plated in matched batches so legs, springs and rockers share the exact same reflectivity when installed side by side.
Product Specification
| Parameter | Value |
|---|---|
| Part Type | Inline Spring Fork Assembly |
| Finish | Chrome (legs, outer springs, rockers), Zinc plated (rocker studs) |
| Length | 18″ (measured from top of rear leg to front axle center line) |
| Stem | 1″ stem |
| Thread | 1″ x 24 thread |
| Neck Bottom | Larger in diameter to accommodate the Lower Race |
| Rear Fork Leg | Not tapped |
| Kit Contents | Front and rear legs, outer springs, rockers, rocker studs; completely assembled |
Fitment
| Platform | Year Range | Notes |
|---|---|---|
| Custom builds | Confirm with model and year | Measurement is taken from the top of the rear leg to the front axle center line. |
Independent aftermarket part. Not manufactured, sold or endorsed by any motorcycle manufacturer. Model names and OEM numbers are used for fitment reference only.
Judging Ride Height Before Ordering
Length measurement methods vary, and guessing the overall height ruins custom geometry.
Springer forks offered over stock often lack a clear statement on how the length is measured, making it hard to judge ride height and steering geometry before ordering. Without knowing the exact reference points, a builder might order a 18″ inline spring fork assembly only to find the front end sits too high or too low for the intended frame rake. We always verify the exact measurement from the top of the rear leg to the front axle center line to ensure the geometry matches the build plan [NEED_CITE: frame geometry and rake calculations for custom springer setups].
Verifying the 18″ Reference Point
The 18″ overall length of this 18″ inline spring fork assembly is strictly measured from the top of the rear leg down to the center line of the front axle. This specific reference point determines how the front end interacts with your frame’s steering neck angle and desired ride height. Confirming this exact dimension against your frame specifications prevents the steering geometry from being thrown off during the build process.
Checking Stem and Tree Compatibility
Before finalizing the order, verify that the 1″ stem and 1″ x 24 thread match your custom triple tree and steering neck specifications. The bottom of the neck is designed with a larger diameter to properly accommodate the lower race, which is a critical detail for smooth steering operation. Overlooking the thread pitch or stem diameter means the assembly will not seat correctly in the trees [NEED_CITE: steering stem thread and diameter standards across custom triple trees].
Understanding the Neck and Leg Specifications
The 1″ stem with a 1″ x 24 thread is the standard interface for mounting this 18″ inline spring fork assembly into most custom triple trees. The neck bottom features a larger diameter specifically machined to accommodate the lower race, ensuring the bearing stack functions correctly without binding. Additionally, the rear fork leg is supplied not tapped, which is a vital detail to note if your build requires direct mounting of brake components or fender brackets to the leg itself.
The Cost of Overlooking Rear Leg Details
Ordering a front end without checking if the rear leg is tapped can halt a build entirely. Since the rear fork leg on this assembly is not tapped, any plan to mount a brake caliper or fender directly to it will require additional fabrication or different mounting brackets. Failing to verify this detail means the bike sits on the lift waiting for custom machining, delaying the entire project timeline and adding unexpected fabrication costs [NEED_CITE: brake and fender mounting requirements for untapped springer legs].
Sourcing Matched Front-End Components
We produce the front and rear legs, outer springs, rockers and zinc plated rocker studs in our own facility, ensuring the chrome finish remains consistent across the entire 18″ inline spring fork assembly. This in-house production allows us to supply the kit completely assembled, ready for your custom triple trees and handlebars. You can order a single sample to verify the fitment and finish quality before committing to a larger batch for your shop.
What Is Included in the Shipment
- Commercial invoice and packing list detailing the 18″ inline spring fork assembly contents.
- Fitment sheet stating the measurement method and applicable custom platform notes.
- Key dimensions including the 18″ length, 1″ stem diameter and 1″ x 24 thread pitch.
- Finish specification confirming chrome on legs, springs and rockers, with zinc plated studs.
- Quality inspection record verifying the completely assembled kit and untapped rear leg.
Inspecting the Assembly Upon Arrival
- Verify the kit includes front and rear legs, outer springs, rockers and zinc plated rocker studs.
- Measure the 18″ length from the top of the rear leg to the front axle center line.
- Check the 1″ stem and 1″ x 24 thread against your custom triple tree specifications.
- Inspect the chrome finish on the legs and rockers for consistency and plating quality.
- Confirm the rear fork leg is not tapped before planning your brake or fender mounts.
- Store the completely assembled 18″ inline spring fork assembly in a dry environment.
Requesting a Fitment Check
Send your frame model, year and steering neck measurements to verify the 1″ x 24 thread stem and 18″ length match your build. Provide photos of your current triple tree or old fork if the part number is unknown. Let us know if you need a single sample to check the chrome finish and fitment before placing a bulk order for your shop.
Frequently Asked Questions
Q: How is the 18″ length of this spring fork assembly measured?
A: The 18″ overall length is measured from the top of the rear leg down to the center line of the front axle. This specific reference point is used to calculate ride height and steering geometry for custom builds. Always compare this exact measurement method to your frame specifications before ordering.
Q: What components are included in the kit and what needs to be ordered separately?
A: The kit includes the front and rear legs, outer springs, rockers and zinc plated rocker studs, supplied completely assembled. You must order the bearing neck kit, axle kit, top tree and handlebars separately to complete the front end installation.
Q: How do I verify the 1″ x 24 thread stem fits my custom triple tree?
A: Check the inner diameter and thread pitch of your custom triple tree’s steering stem hole. The 1″ stem with a 1″ x 24 thread must match these specifications exactly for the assembly to seat correctly. If your trees use a different metric or imperial thread, this stem will not fit.
Q: Can I order a single sample to check fitment and chrome finish before a bulk order?
A: Yes, we support a minimum order of one piece. You can order a single 18″ inline spring fork assembly to verify the dimensions, thread pitch and chrome finish quality against your custom build requirements before committing to a larger batch for your shop or dealership.
Q: What is the difference between the front and rear legs in this assembly?
A: Both legs feature a matching chrome finish and are supplied completely assembled with the rockers and springs. The primary difference is that the rear fork leg is not tapped, meaning it lacks pre-drilled and threaded holes for direct mounting of brake calipers or fender brackets, which may affect your mounting plans.