Search  for anything...

1Pair Bike Handlebars Shim Bicycle Clamp Spacers 25.4-31.8MM Conversion Adapter Cycling Aluminum Alloy Stems Reducer Mountain Bike Parts and Components

  • Based on 37 reviews
Condition: New
Checking for product changes

Buy Now, Pay Later


As low as $1 / mo
  • – 4-month term
  • – No impact on credit
  • – Instant approval decision
  • – Secure and straightforward checkout

Ready to go? Add this product to your cart and select a plan during checkout.

Payment plans are offered through our trusted finance partners Klarna, PayTomorrow, Affirm, Afterpay, Apple Pay, and PayPal. No-credit-needed leasing options through Acima may also be available at checkout.

Learn more about financing & leasing here.

Selected Option

Free shipping on this product

Eligible for Return, Refund or Replacement within 30 days of receipt

To qualify for a full refund, items must be returned in their original, unused condition. If an item is returned in a used, damaged, or materially different state, you may be granted a partial refund.

To initiate a return, please visit our Returns Center.

View our full returns policy here.


Availability: In Stock.
Fulfilled by Amazon

Arrives Tuesday, Jun 24
Order within 22 hours and 47 minutes
Available payment plans shown during checkout

Style: Black


Features

  • [Adapt Size] The size of the bike stem adapter is 25.4-31.8MM. If your handlebar diameter is 25.4mm and stem diameter is 31.8mm, then you can use a "25.4 to 31.8mm" handlebar shim as a conversion.
  • [Good Quality] This bicycle handlebar spacer is forged from high-strength aluminum alloy for high strength and corrosion resistance. It's not easy to rust or fade and sturdy.
  • [Function] This reducer allows you to use a smaller diameter standard size handlebar in an oversized stem. Bicycle handle gasket reducer converts 25.4mm to 31.8mm rod hole adapter.
  • [Styling] CNC machining. Using CNC cutting, the surface is flat and beautiful, and the edges are round and smooth. The surface is anodized and brightly colored, making your bike cooler and more stylish.
  • [Special Design] This bike clamp spacer adopts a wavy design on the surface not only will not damage the handlebar and stem, but also increase the friction of the product. It can be better anti-skid and improve riding safety.

Color: black


Brand: SeonFook


Material: Aluminum


Bike Type: Mountain Bike


Manufacturer: ‎SeonFook


Brand: ‎SeonFook


Model: ‎SF-US-024


Item Weight: ‎0.317 ounces


Package Dimensions: ‎4.37 x 2.83 x 0.75 inches


Country of Origin: ‎China


Item model number: ‎SF-US-024


Exterior: ‎aluminum alloy


Manufacturer Part Number: ‎SF-US-024


Date First Available: April 15, 2022


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Tuesday, Jun 24

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.

  • Klarna Financing
  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
  • PayTomorrow Financing
  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Top Amazon Reviews


  • The interior and exterior grooves make the difference
Style: Red
Very happy so far with the performance of this 25.4mm to 31.8mm. Bought this "size adjuster" handlebar shim due to the wrong size bicycle stem being sent. I have a 25mm handlebar and was sent a 31.8 handlebar stem. This shim comes grooved both on the interior and exterior of the shim for extra non slip grip and was machined to the perfect size and was exactly what I needed. Would recommend. ... show more
Reviewed in the United States on April 6, 2024 by Kindle Customer

  • excellent
Style: Black
these work. they may require some manipulation..but they will work.
Reviewed in the United States on March 21, 2024 by Sweet Mammaries

  • Great product
Style: Red
Works great no regrets
Reviewed in the United States on March 6, 2024 by Mario

  • Eh
Style: Red
Too big for my 25mm bars.
Reviewed in the United States on March 23, 2024 by Power User

  • As described
Style: Red
Fit, works as described.
Reviewed in the United States on July 30, 2023 by Mamaphipps

  • Adapter
Style: Black
Perfect exact fit
Reviewed in the United States on September 22, 2023 by Brett sr

Can't find a product?

Find it on Amazon first, then paste the link below.