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Profile Design Threadless Size Converter (1" - 1 1/8")

  • Based on 1,167 reviews
Condition: New
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Availability: 11 left in stock
Fulfilled by Rapid Warehousing

Arrives Jul 20 – Jul 22
Order within 5 hours and 43 minutes
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Color Name: Silver


Features

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

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

Item Package Dimensions L x W x H: ‎7.44 x 3.23 x 2.24 inches


Package Weight: ‎0.19 Kilograms


Item Dimensions LxWxH: ‎5.75 x 1.25 x 1.5 inches


Item Weight: ‎0.25 Pounds


Brand Name: ‎Profile Design


Warranty Description: ‎Limited Warranty


Model Name: ‎Threadless Converter


Color: ‎Silver


Material: ‎Multi


Suggested Users: ‎All Ages/Unisex


Number of Items: ‎1


Manufacturer: ‎Profile Design


Part Number: ‎15920002


Model Year: ‎2016


Style: ‎Stem Column Adaptor


Included Components: ‎Stem Column Adaptor


Date First Available: September 24, 2009


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Jul 20 – Jul 22

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • The best I have seen for this purpose.
Very high-quality, thoughtful design. Materials are excellent and the finish is nice. Tight tolerances-grease will be necessary for surfaces, and the bolt and wedge should have grease too.
Reviewed in the United States on June 4, 2026 by no

  • solution for using a threadless stem.
works as intended,quality brand.
Reviewed in the United States on April 3, 2026 by royalOaker

  • 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. ... show more
Reviewed in the United States on August 8, 2024 by letmepicyou

  • Almost perfect
Let's clear some things up on this one. Yes, the top compression cap is separate and does come off. You will not be able to use a standard 1-1/8" compression cap on this because the bolt on this is bigger than a standard compression bolt for a 1-1/8" stem cap. The compression cap on this is wider than a standard compression cap by 2mm, it is too big to fit down into a compression cap recess on a stem.. why????? Who knows. This thing would be perfect if not for that. I will have to have it machined down to fit like a standard cap.. It is well made, I wish it didn't have the logo on the cap (get out your buffer) and I wish the cap was 2mm smaller to fit down in a compression cap recess. Not bad for the price, but needs mods to be perfect.. Has potential! Ha! ... show more
Reviewed in the United States on January 16, 2021 by matt b

  • Schwinn component modernization.
Looks good. Fit perfectly.
Reviewed in the United States on May 6, 2026 by Just Me

  • Easy solution to vintage issue.
I bought an early 90's vintage very high-end steel bike frame. Turns out it is getting pretty difficult to find stems and handlebars in the 'old' specifications, without spending a ton of money. So, this riser allowed me to not only easily set up my bike, but use a modern handlebar & stem. So, very economical solution. Not too much heavier than traditional components, because I could use a much lighter modern handlebar. Not quite as sleek looking as traditional components, but quite acceptable. ... show more
Reviewed in the United States on June 19, 2023 by flashsteve

  • Great looking item, mislabeled from manufacturer wrong size
Nice product, terrible description and although it’s advertised and labeled the size I needed on the item description and on the packaging, it was the wrong size. Was supposed to be 1 1/8”-1” but was 1 1/8” - 7/8” . Frustrating
Reviewed in the United States on May 31, 2026 by Ken M.

  • Does the job, understand the size you need, assembly takes more work.
This is a well-priced, good-looking aluminum adapter that lets you mount a 1 1/8" newer style stem on a bike with an older (or cheaper) 1" steering tube. Two things to pay attention to: 1. Make sure that you are buying the right size (as many buyers seem surprised.) When your bike has a "1 inch" steering tube, the shaft that fits inside the stem (i.e., your old stem or this new adapter) will be thinner, about 7/8"/22.2mm. If your old stem is 7/8"/22.2mm thick, your steerer is 1" and this adapter will fit. (Your steerer is measured on its outside, but you may not be able to actually see the tube on many bikes.) If the shaft of your old stem is thicker than 7/8"/22.2mm, your steerer is not 1". Also be sure that the thicker top part of the shaft (where you mount the new stem) is correct for your new stem. This adapter takes stems that are 1 1/8"/28.8mm, a common size (though some stems are larger or smaller.) 2. Unlike similar adapters, the top cap on this one is wider than the opening in your stem. You can't mount the adapter on the bike, then mount the stem on the adapter. Rather, you'll need to assemble the adapter and your new stem off the bike, then insert the combined unit into the steering tube. The payoff for your efforts is a cap that covers the joint between the stem and the adapter. That will likely keep water from seeping into your assembly and also looks more elegant. ... show more
Reviewed in the United States on November 24, 2020 by Isaac B

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