Promax SP-877 Suspension Seatpost
Ride farther, longer and more comfortably with the Promax SP-877 Suspension seatpost. With 40 mm of suspended travel, it takes the edge off commutes, off-road ventures or quick spins around the block.
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- Crafted from 2014-series aluminum alloy for strength and weight savings
- Designed to limit side-to-side play for a stable feel
- Dual-bolt saddle clamp for standard rails
Imported.
View all Promax Suspension Seatposts| Best Use | Cycling |
|---|---|
| Seatpost Diameter | 27.2 MM x 350 MM x 0 MM: 27.2 millimeters |
| Seatpost Length | 350 millimeters |
| Seatpost Setback | 12 millimeters |
| Seatpost Travel | 40 millimeters |
| Seatpost Suspension Type | Coil Spring |
| Seatpost Material | Aluminum |
| Weight | 425 grams |
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Get What You Pay For
Bought this to add a little comfort on my electric bike. First thing I noticed is that it’s a fairly light for a suspension seatpost. Positives: light weight, inexpensive, and easy to adjust. Negatives: the compression has too much stiction regardless of preload adjustment. I tried to adjust the preload to minimize the stiction but with no luck. Also, the compression deflections in a vertically linear motion giving one a pogo like feel. I returned it and purchased a SR Suntour XCR four linkage post that provides a smoother radial compression. It’s a heavier post, but the comfort out performs the Promax without a pogo like travel.
excellent for the money
I bought this as a less expensive way to make my city rides smoother. It does exactly that, it’s obviously not going to give you same as a full suspension but it’s a solid build.
Feels great on the whole!
i bought thus for my gravel bike to give a suspension seatpost a try without breaking the bank. This seatpost has exceeded expectations so far. Great fit and finish, quality construction, and plenty of adjustability.
Worth it!
Best $50 I've spent on my sirrus x gravel bike. Not the smoothest, but it definitely takes out the jarring bumps. I'm 220lbs and it feels good out of the box. It is threaded internally at the bottom of the post, but I'm not sure if that can be used for adjustment based on rider weight.
Better Than Nothing
I got this for my e-bike, and it's an improvement over the fixed seatpost, but it's definitely built to a price point. It takes the sting out of bumps, however there's a lot of stiction in it. But for the price there's not much else available.
Gamechanger for long rides on bumpy trails.
Gamechanger for long rides on bumpy trails. Did a 42 mile with standard post, then a 48 mile ride on this post. Night and day, well worth the upgrade.
helps a little.
I used this last summer, 2024. On a week tour I accidently moved the bike over a curb by picking it up from the seat. The post came apart. then picked up the pieces and put it back together before riding the last 20 miles home. Thankfully, it is not a complicated accessory.
does not fit Specilized Haul LT
this is extremely tight for Specilized Haul LT. I really tried and tried but it just so tight, it does not fit beyond an inch, I compared it to the original post and its just a hair thicker (we are talking less than 1mm)
Suspension seat post
Easy to install and much better than original post