Free Shipping / Returns for US, UK, EU, & CAN - 10% OFF Your 1st Order!

Free Shipping / Returns for US, UK, EU, & CAN - 10% OFF Your 1st Order!

Scratch & Dent - Dual-Position Seatpost

Regular price
Sale price

Scratch & Dent - Dual-Position Seatpost

Regular price
Sale price
The patented Dual-Position Seatpost lets you switch between road and aero positions on-the-fly while riding, so you can choose the best riding position for every part of your ride. The forward position of the seatpost allows you to ride with proper aero bike fit on a standard road bike, letting you ride faster and more comfortably. 


What is a Redshift "Scratch and Dent" product:

That means that for whatever reason, this particular product didn’t live up to our high standard of quality, but is still perfectly safe to ride - and therefore available to you for a discount!

There may be a cosmetic issue, damage to the outer packaging, or the product was installed on a bike to test fit or take some photos. Often times these products are completely new!

Scratch and Dent products are not available in the UK, EU, AUS, and CAN. Additionally, you can not apply discounts to Scratch and Dent products.

NOTE: Physical performance & durability are not compromised in any way. So all Scratch and Dent products are still covered by our lifetime warranty, however ALL SALES ARE FINAL, and our 90 Day Risk Free Trial does not apply.

Product Description: The patented Dual-Position Seatpost lets you ride a true aero position on a standard road bike, without sacrificing your normal road position. Along with the Quick-Release Aerobars it provides the benefits of a triathlon or time trial bike without the additional bike or price tag. The key to riding powerfully and comfortably is proper saddle position and since you can switch between road and aero positions on-the-fly while riding, you can always choose the best riding position for every part of your ride.


• Transform your current bike - switch from road to aero position on the bike you already own
• Ride with ease - no more time and energy wasted switching from road bike to aero bike


• Linkage design lets you switch between road and aero positions seamlessly while riding
• Choose the best position for every single climb, flat, or descent
• Maintain proper leg extension in both road and aero positions
• Saddle moves forward 50mm, corresponding to approximately 4 degrees of effective seat tube angle change
• Aero road riding position optimized for proper handling on a road bike
• Simple, durable two-bolt saddle clamp allows infinite saddle tilt adjustment and reliable clamping
• 16mm rearward setback (road position)
• Check technical specifications for compatibility

What's in the Box:

• 1 x Dual-Position Seatpost
Weight400 g
Seatpost Diameter (A)27.2 mm
Seatpost Length (B)350 mm - (bottom to clamp centerline)
Minimum Insertion (C)75 mm
Rearward Offset
Road Position (D)
16 mm
(post centerline to clamp centerline)
Forward Offset
Aero Position (E)
34 mm
(post centerline to clamp centerline)
Total Travel
Road to Aero Position
50 mm
(3-4 degrees effective seat tube angle change)
Saddle Rail CompatibilityStandard 7 mm round saddle rails only
MaterialLinkages & saddle clamps - 7075 T6 aluminum
Post - 6061 T6 aluminum
Rider Weight Limit115 kg (250 lb)

Will my saddle bag fit with the Dual-Position Seatpost?

Most standard strap-based saddle bags will fit the dual-position seatpost without issue.
You may need to loosen the straps slightly to accommodate the movement that occurs between road and aero positions. If your saddle bag uses rigid clips, clamps, or some other inflexible attachment method, it's possible that your bag may not be compatible.
Here is an example bikepacking saddle bag from one of our ambassadors that works just fine with the Dual-Position Seatpost:

If you have questions about your specific bag, please email us at and we'll help you figure it out!

Is the Redshift Dual-Position Seatpost legal to use in a triathlon race?

Yes! The Dual-Position Seatpost is legal for use in any non-drafting triathlon. That includes all Ironman events, USAT sanctioned events, and the vast majority of triathlons worldwide. The only events where the seatpost is not permitted are draft-legal events, which are relatively uncommon. If you're wondering about a specific race, shoot us an email at and we'll help you figure it out.

Will the Dual-Position Seatpost fit a Shimano Di2 battery inside?

Yes, the standard "lipstick" style Shimano Di2 battery will fit inside the seatpost. Keep in mind that the inner diameter of the seatpost is ovalized, so standard round battery mounts may not be compatible. We have found that wrapping the battery with a thin layer of packing foam is usually sufficient to secure the battery within the seatpost.

To read more Frequently Asked Questions, click here.


Download Instructions (PDF):
Instructions - Dual-Position Seatpost


Different bikes sometimes have different seatpost diameters. The ShockStop Seatpost is 27.2mm in diameter, so if your bike's seatpost is larger, you'll need a shim to adapt our seatpost to your bike's frame. Don't worry though, the shims are super-lightweight and essentially invisible once installed.

Not sure what size seatpost you have currently? There are a couple different ways to find out.

Most seatposts have the diameter printed somewhere near the bottom of the post. You'll need to remove the seatpost from the bike frame (mark your existing seatpost height with a bit of tape before you remove it so you can replace it easily), and look for a number like 27.2, 30.9, or 31.6 (etc.). That is the diameter of the post.
If you know the make, model, and year of your bike, you may be able to look up the seatpost diameter online. Feel free to shoot us an email at - we'll see if we can help out.
Ask your local bike shop - they'll be able to accurately measure your bike's seatpost.

Non-compatible posts: Unfortunately, if your bike's seatpost is smaller than 27.2mm (for example, the 25.4mm posts found on some recent model Cannondale Synapses) our seatpost is currently not compatible with your bike. Likewise, if you have a bike with an aero/oval/non-round seatpost, or if your bike has an integrated seatmast, the seatpost is also not compatible.

Currently, the Redshift Dual-Position Seatpost is only offered in one diameter (27.2mm). If your bike has a different seatpost diameter, check out the shim options below to find the right one for your bike. In addition to the standard black-anodized aluminum post, we also offer an aluminum version with red-anodized linkages.

clip on quick release aerobars
Quick-Release Aerobars