---
product_id: 2487386
title: "Profile Design Threadless Size Converter (1\" - 1 1/8\")"
brand: "profile design"
price: "€ 47.59"
currency: EUR
in_stock: true
reviews_count: 10
category: "Profile Design"
url: https://www.desertcart.be/products/2487386-profile-design-threadless-size-converter-1-1-1-8
store_origin: BE
region: Belgium
---

# Fits 1" to 1-1/8" steerer tubes Ultra-light 0.8 oz weight Threadless stem conversion Profile Design Threadless Size Converter (1" - 1 1/8")

**Brand:** profile design
**Price:** € 47.59
**Availability:** ✅ In Stock

## Summary

> ⚡ Upgrade your ride, ditch the old tech, and join the threadless revolution!

## Quick Answers

- **What is this?** Profile Design Threadless Size Converter (1" - 1 1/8") by profile design
- **How much does it cost?** € 47.59 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.be](https://www.desertcart.be/products/2487386-profile-design-threadless-size-converter-1-1-1-8)

## Best For

- profile design enthusiasts

## Why This Product

- Trusted profile design brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Featherlight Build:** At just 0.8 ounces, it adds zero bulk while boosting your bike’s performance.
- • **Polished Silver Finish:** A premium, corrosion-resistant sheen that elevates your bike’s aesthetic and durability.
- • **Versatile Rise Adjustment:** Gain up to 25mm rise with spacers for a customized, comfortable riding posture.
- • **Precision Fit for 1" & 1-1/8" Tubes:** Engineered to perfectly convert between standard quill sizes, ensuring a rock-solid fit.
- • **Seamless Quill-to-Threadless Upgrade:** Effortlessly modernize vintage forks with threadless stems for sleek compatibility.

## Overview

The Profile Design Threadless Size Converter is a precision-engineered adapter that converts traditional 1" quill forks to modern 1-1/8" threadless stems. Weighing only 0.8 ounces and finished in polished silver, it offers a lightweight, durable solution for vintage bike upgrades or custom builds. Compatible with standard steerer diameters and allowing up to 25mm rise adjustment with spacers, it’s the perfect component for riders seeking seamless integration and enhanced bike ergonomics.

## Description

Profile Design Conversion has a polished silver finish. Features: For installing threadless stems on a threaded fork Approximately 25mm rise increase possible if used with spacers Polished silver finish Quill Insertion Diameter: 25.4mm for 1 1/8" stems and 22.2 for 1" stems Steerer Clamp OD 25.4mm, for 1", 28.6mm fir 1-1/8

Review: Works great for my application! - I'm currently in the process of building a trike out of a very old (somewhere between the 50's and 80's, I've yet to find anything on the serial number) Schwinn (at least, I THINK it's a Schwinn, lol) that had some very old tech on it. Such as a threaded headset and the old cup and ball style bottom bracket...lol, yeah, that old. So I already got myself a bottom bracket converter so I can run a normal threaded bottom bracket cartridge (which sure makes maintenance a breeze), but I was on the hunt for a front fork to replace the stock fork, as I was converting it from a 24" skinny tire trike to a 20" FAT TIRE trike (lol) and wasn't sure what I was going to have to get, stem-wise, until I found a fork. Well, I finally found myself a front suspension for a 20" x 4" fat tire (already have all 3 rims, thankfully), and since it had a 1" threadless tube, I knew I needed an adapter for the fork...which leads me to this, lol. This works in my new suspension fork beautifully! I still have to get replacement cups and bearings for the headset, as there's no way I'm re-using the old cups and bearings. I saw quite a few bearing indentations from years of riding a rigid-forked bike and smacking pot holes and curbs and whatnot. In fact, a little PRO TIP for the day is to always run a suspension fork of some kind if your bike allows for it...it not only saves wear and tear on your wrists, elbows, and shoulders, but a front suspension fork, no matter what kind, can prevent impact damage to your headset bearing and cups...the suspension absorbs energy that would otherwise be transferred to the bearings and cups, causing indents and thus irreparable damage to the bearing surface. Anyway, I have to pick up new bearings, so I don't have this installed yet, but when I do, I'll upload a pic with the new fork / wheel / tire installed on the old frame. But as I said, it works great for my application. If you're converting an old threaded trike to a threadless setup like mine, this should work GREAT for you. 5 stars.
Review: Fits a Specialized Hotrock 1995 MTB like a glove. - Likes: Fits my bike project like a glove. solid material very durable amazing workmanship Concerns: None Kept or Returned? Kept and installed on my Fixie bike and it works like a charm. Thanks for your time and I hope this review was helpful.

## Features

- Converts all quill style forks to use threadless stems
- Converts 1 inch to 1-1/8" threadless
- Weight: 0.8 ounce

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B0028N14GQ |
| Best Sellers Rank | #92,274 in Sports & Outdoors ( See Top 100 in Sports & Outdoors ) #53 in Bike Stems |
| Brand Name | Profile Design |
| Color | Silver |
| Customer Reviews | 4.4 4.4 out of 5 stars (1,256) |
| Date First Available | September 24, 2009 |
| Included Components | Stem Column Adaptor |
| Item Dimensions LxWxH | 5.75 x 1.25 x 1.5 inches |
| Item Package Dimensions L x W x H | 9.37 x 3.23 x 1.14 inches |
| Item Weight | 0.25 Pounds |
| Manufacturer | Profile Design |
| Material | Multi |
| Model Name | Conversion |
| Model Year | 2016 |
| Number of Items | 1 |
| Package Weight | 0.2 Kilograms |
| Part Number | 15920002 |
| Style | Stem Column Adaptor |
| Suggested Users | All Ages/Unisex |
| Warranty Description | Limited Warranty |

## Images

![Profile Design Threadless Size Converter (1" - 1 1/8") - Image 1](https://m.media-amazon.com/images/I/61hGhncU3oL.jpg)

## Questions & Answers

**Q: My kid lost that small base piece to his "20" Thruster Dirt DS Boys' Mountain Bike" Will this work as a replacement?**
A: It depends on the size of the steer tube and stem sizes. I'd the bike has a one inch threaded steer tube it'll work. But, you may have to get a new stem with a 1 1/8 inch collar.

**Q: how many spacers could be fit under this adapter?**
A: You don't use spacers for this. You only use spacers for a real threadless setup. This just emulates a threadless and allows you to use a 1-1/8 stem. You just set the height you want and tighten the allen bolt

**Q: what stem size does it fit? 1" or 1 1/8"**
A: 1 1/8".It inserts into forks with 1 1/8" threaded headsets (actual diameter measurement is 1"). It fits 1 1/8" threadless stems (1 1/8" actual measurement).

**Q: How high can you raise the stem above the headset?**
A: I have lifted my stem by 25mm from the top of the threaded steerer into which the extender inserts. Done roughly 2500km, including a 500km bike tour over gravel terrain - no issues whatsoever.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Works great for my application!
*by L***U on August 8, 2024*

I'm currently in the process of building a trike out of a very old (somewhere between the 50's and 80's, I've yet to find anything on the serial number) Schwinn (at least, I THINK it's a Schwinn, lol) that had some very old tech on it. Such as a threaded headset and the old cup and ball style bottom bracket...lol, yeah, that old. So I already got myself a bottom bracket converter so I can run a normal threaded bottom bracket cartridge (which sure makes maintenance a breeze), but I was on the hunt for a front fork to replace the stock fork, as I was converting it from a 24" skinny tire trike to a 20" FAT TIRE trike (lol) and wasn't sure what I was going to have to get, stem-wise, until I found a fork. Well, I finally found myself a front suspension for a 20" x 4" fat tire (already have all 3 rims, thankfully), and since it had a 1" threadless tube, I knew I needed an adapter for the fork...which leads me to this, lol. This works in my new suspension fork beautifully! I still have to get replacement cups and bearings for the headset, as there's no way I'm re-using the old cups and bearings. I saw quite a few bearing indentations from years of riding a rigid-forked bike and smacking pot holes and curbs and whatnot. In fact, a little PRO TIP for the day is to always run a suspension fork of some kind if your bike allows for it...it not only saves wear and tear on your wrists, elbows, and shoulders, but a front suspension fork, no matter what kind, can prevent impact damage to your headset bearing and cups...the suspension absorbs energy that would otherwise be transferred to the bearings and cups, causing indents and thus irreparable damage to the bearing surface. Anyway, I have to pick up new bearings, so I don't have this installed yet, but when I do, I'll upload a pic with the new fork / wheel / tire installed on the old frame. But as I said, it works great for my application. If you're converting an old threaded trike to a threadless setup like mine, this should work GREAT for you. 5 stars.

### ⭐⭐⭐⭐⭐ Fits a Specialized Hotrock 1995 MTB like a glove.
*by A***O on December 25, 2024*

Likes: Fits my bike project like a glove. solid material very durable amazing workmanship Concerns: None Kept or Returned? Kept and installed on my Fixie bike and it works like a charm. Thanks for your time and I hope this review was helpful.

### ⭐⭐⭐⭐⭐ Cheap, ultra fast shipping and exactly as described
*by F***N on November 11, 2019*

Perfect fit for what I would assume most standard tube size. Plenty of room for height adjustments for anyone wanting a more upright feel. Mine is set to the lowest possible setting with a little bit of it still exposed. Which is fine since it looks pretty damn sexy. Could not imagine this thing failing at any point due to its solid build. I love that it has a brand on the top rather than creating a gaping hole in your stem. This stem went onto a 2019 retrospec harper bike. For anyone trying to fit this on that frame, don't stress, it fits like butter baby!!!

## Frequently Bought Together

- Profile Design Threadless Size Converter (1" - 1 1/8")
- SHIMANO Universal Standard Brake Cable Set, For MTB or Road Bikes
- Park Tool PolyLube 1000 Bicycle Grease

---

## Why Shop on Desertcart?

- 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016
- 🌍 **Shop Globally** — Access 737+ million products across 21 categories
- 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price
- 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members)
- 🔒 **Secure Payments** — Trusted payment options with buyer protection
- ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews

**Shop now:** [https://www.desertcart.be/products/2487386-profile-design-threadless-size-converter-1-1-1-8](https://www.desertcart.be/products/2487386-profile-design-threadless-size-converter-1-1-1-8)

---

*Product available on Desertcart Belgium*
*Store origin: BE*
*Last updated: 2026-04-23*