My friend Joe gave me a late 1990s Softride Powercurve Solo road bike that reportedly hadn't been getting ridden much. Not that I was hurting for another bicycle project, but I'd been interested in Softride bikes for a while. He rightly assumed that I would give it the love, care, and miles that such a distinctive machine deserves.
Softride, Inc. pulled out of the bicycle business in 2007 (15 years ago as of the time of writing), and no longer supports any bicycles1. Official replacement parts for the unique beam suspension system are no longer manufactured, and new-old-stock parts are sometimes hard to come by. Additionally, technical documentation has been removed from public view on Softride's website, leaving only forum posts from the mid-aughts full of anecdotal and sometimes dubious knowledge and advice.
Combine all of these factors, and you end up with a sizable knowledge gap on the Internet surrounding the maintenance of the suspension system. While I did dig up the official documentation from the manufacturer thanks to the Wayback Machine's archived copy of softride.com, it doesn't delve into the details that a shadetree mechanic like myself would find useful.
On this page, I've captured photos and notes from my attempt to follow the instructions for routine maintenance on the beam pivot assembly. I've also documented the unique components of the beam suspension system as 3D models and mechanical drawings.
This website is not affiliated with nor endorsed by Softride, Inc., nor are any of the replacement parts or procedures described on this page. The Softride name, logo, and device are registered trade marks of Softride, Inc.
Some documentation excerpts and images used on this page have been sourced from an archived copy of Softride.com. This content is copyright Softride, Inc.
- Softride Rear Suspension Overview
- Supporting the Softride Frame for Work
- Beam Removal
- Beam Installation
- Wear Analysis
- Closing Notes
Softride Rear Suspension Overview
There are two different SRS carbon fiber beams: Classic and Rocket. The Classic beam features three segments of different widths and thicknesses, while the Rocket beam is straight and has constant width and thickness across its entire length. This page only covers the Classic beam; nothing here applies to the Rocket beam as it incorporates very different mounting mechanisms.
The Classic beam attaches to the frame in two places: A pivot assembly at the front of the frame's top tube, and a height adjustment bracket a little further back. When the height adjustment hardware is loosened or removed, the beam can swing up and down freely; this is equivalent to adjusting seat post height on a traditional double-diamond frame (though it's often necessary to adjust the saddle's forward position and pitch on the opposite end of the beam at the same time).
The beam flexes in both the rear section (behind the height adjustment bracket) and the front section in response to perturbances on its load. To allow this, the pivot assembly has another very limited degree of freedom besides tilt angle, where it can slide forward and backwards on the pivot point.
The pivot assembly is comprised of several load-bearing parts, centering around an eye bolt. This eye bolt's threads engage with both a threaded insert embedded in the carbon fiber and a nut that clamps onto a metal tray inside the middle of the beam.
The unique wear items in this setup are the eye bolt and supporting hardware 23. Softride recommended replacing these parts every 2 years or 5,000 miles. Anecdotes on the Internet suggest that this part is good for a far longer service life. In the case of my bike, the eye bolt had seen at least that many miles before I replaced it, and could even be original to the frame.
Supporting the Softride Frame for Work
Generally, the only part of a bicycle frame that should be clamped by a repair stand is the seat post; clamping the tubes of the frame risks crushing them, especially aluminum tubes. Obviously this isn't possible on a bicycle that doesn't have a traditional seat tube and post, so one has to either get creative with a traditional clamping repair stand, or use a different style of repair stand entirely.
While working on my Softride, which involved stripping the entire bike down to the frame and overhauling every component, I did a bit of both. I used my basic clamping stand, and lightly clamped the frame on the diagonal "top tube" on or near the threaded bungs.
I recognize there's some risk in doing this, and took care while rebuilding the bike to not clamp its frame too tightly, or put excess torque through the frame. For torque-intensive tasks, like removing and installing the bottom bracket and crank arms, I took the frame off the stand, put wheels in its dropouts, and mounted it in a turbo trainer on the ground.
I think this is my new favorite way to install and remove crank arms, since a jack stand (pictured) can be placed under an arm while wrenching on the crank puller to provide an opposing force.
In a perfect world, a frame like this would be supported from underneath, such that the tubes never see any clamping force. Something like Park Tool's PRS-22.2 would work well.
I didn't know what I was doing when I first started this job.
Some photos depict the beam still attached to the frame after it was removed in a preceding step, or the frame being held by its downtube in the repair stand. Both of these practices are wrong and were ultimately corrected. The following steps reflect the correct procedures, but in some cases I forgot to retake photos depicting them.
Initially, I wasn't aware that the eye bolt was threaded into not only a hex nut inside the beam's cavity, but also a threaded insert embedded in the carbon fiber.
After reading some unfounded claims on the Internet that driving the pivot pin out could damage the carbon fiber beam, I was hesitant to follow the official maintenance instructions. I thought I could avoid this (nonexistent) issue by removing the nut and washers, and lifting the beam off the eye bolt first. This turned out to be impossible, and I ended up following the official instructions (mostly) to a tee and nothing bad happened.
This just highlights the need for clear instructions to combat some of the blatant misinformation that's out there.
- (Optional) Take measurements of the beam height and saddle position (if also removing the saddle bracket assembly).
- (Step 1 of Rebuild Kit Instructions) Remove the height adjustment bolt, nut, and washer. Without any weight on the beam, the friction between the height adjustment bracket and frame endcaps should keep the beam in place.
(Step 1 of Rebuild Kit Instructions) Drive out the pivot pin using a 5/32" punch from the rider's left side.
As I received the bike, the pin stuck out on the rider's right side about 1/8", and was slightly recessed on the left side.
I used a 16oz ball peen hammer, but a lighter hammer could have worked just as well. Light, successive taps with the hammer were sufficient to drive the pin out.
I was most concerned about this part of the procedure. However, all of the binding is between the pin and the brackets on the frame, and not the eye bolt. The pin should turn freely within the eye bolt; they should have a close fit, but not quite a "slip fit".
(Step 2 of Rebuild Kit Instructions) Lift the SRS beam straight up to remove it from the frame. Then, exactly per Softride instructions:
Place beam on workbench (height adjustment bracket down) for access to the 101 cavity.
(Step 3 of Rebuild Kit Instructions) Pry off the dust cover.
I used a plastic tire lever, thinking it might damage the soft plastic dust cover less than other tools.
(Step 3 of Rebuild Kit Instructions) Lift out the nut retainer.
Nothing's really holding the nut retainer besides old grease. It can be lifted out with a screwdriver or similar tool.
(Step 4 of Rebuild Kit Instructions) Exactly per Softride instructions:
Using the 7/16" nut driver, remove pivot bolt nut (part #16254).
(Step 5 of Rebuild Kit Instructions) Exactly per Softride instructions:
Using the adjustable wrench, back out the rolled threaded eyebolt (part #20865). The pivot bolt bottom support steel washer (part #16748) should come off with this.
(Step 6 of Rebuild Kit Instructions) Exactly per Softride instructions:
Lift out pivot bolt steel washer (part #15764) and the pivot bolt silicon bronze washer (part #15765).
The same small screwdriver used for the nut retainer did the trick. I was careful not to catch the exposed carbon fiber inside the cavity.
(Step 7 of Rebuild Kit Instructions) Clean old grease and other debris out of the beam's cavity.
I used a flat blade screw driver and a rag to scrape out the old grease. The old grease was black, making it kind of hard to distinguish from the carbon fiber, so I had to be careful not to catch or gouge it.
The rebuild kit instructions say to discard all parts except the 101 pin. I didn't do this because I wanted to keep the original parts for comparison later on. I also kept the nut to reuse.
It was here I discovered that there are two separate parts embedded in the carbon fiber in the cavity - the anti-friction tray and a threaded insert.
Beam installation more or less follows the beam removal instructions in reverse.
Pick a replacement support washer.
The support washer's thickness affects the torque required to achieve the correct clocking of the pivot bolt.
I checked the thickness of several replacement support washers in the pack I received. There was a tolerance of 0.06" to 0.09" listed online, but I found they all measured exactly 0.075". Compared to the original of 0.079", I figured this was close enough. This may vary from batch to batch.
- (Step 1 of Rebuild Kit Instructions) Place the new support washer on the new eye bolt. Partially screw it into the beam, such that it protrudes past the anti-friction tray about 1/4".
(Step 3 of Rebuild Kit Instructions) Place the bronze washer (first) and steel washer (second) on the eye bolt and against the beam's anti-friction tray inside the cavity.
I tried following Softride's instructions, where this was done after screwing the eye bolt all the way into the beam, but there wasn't enough clearance in the cavity to push the washers down.
I never tried removing these washers with the bolt still inserted through the bottom, but it probably wouldn't have worked for the same reason.
(Step 2 of Rebuild Kit Instructions) Screw the eye bolt into the beam's threaded insert until it's finger-tight, then further tighten it with an adjustable wrench until the "axis of the [eye bolt's] hole is perpendicular to the centerline of the rear suspension".
To get a better visual of the eye bolt's clocking, I stuck the pin through it.
(Step 4 of Rebuild Kit Instructions) Spin the nut onto the bolt and tighten it using a nut driver until it makes contact with the washers.
I found differing instructions regarding how much to tighten the nut. The rebuild kit instructions say to:
Tighten until the next two parallel sides of the nut are parallel with the axis of the beam.
So, not a whole lot, depending on how the nut landed when it started contacting the steel washer. However, in a forum post on Slowtwich4, Adam Greene, formerly of Softride, Inc. says:
One recommendation listed in this thread that I would be cautious of is the tightening of the nut on the front attachment assembly of the Classic beam. The nut should be tightened 1 revolution after initial contact with the washer.
A full revolution of the nut is a bit more torque than turning it until the sides are parallel with the beam's centerline. Furthermore, the SRS Instructions document states:
Tighten nut until you feel shear layer material begin to clinch.
I ended up following the rebuild kit instructions, and turned the nut an additional ~1/6 turn to line it up for the nut retainer.
(Step 6 of Rebuild Kit Instructions) Apply grease to the components inside the beam's cavity.
Initially, I stuck the nut retainer onto the nut before applying the grease, but I took it back out for better access to the lower region of the beam's cavity.
Without seeing the original grease packet referenced by the instructions, I don't know how much grease was supposed to be used. I filled the cavity and spread it around with a rag, and applied a bit more after adding the nut retainer. I figured this was in the spirit of the SRS Instructions:
Never let anti-friction tray get dry!
The instructions call for Finish Line Synthetic Teflon Grease. I didn't have any of that on hand, but I did have a tub of ceramic grease, so I used that instead. To follow the instructions exactly, Finish Line's Premium Grease looks like the right stuff.
(Step 5 of Rebuild Kit Instructions) Exactly per Softride instructions:
Place the red pivot nut retainer (part #16048) onto pivot bolt nut.
(Step 7 of Rebuild Kit Instructions) Exactly per Softride instructions:
Replace dust cover (part #15618).
Before putting the beam back onto the frame, I popped both of the height adjustment endcaps out of the frame. I wiped the old grease off them, and cleaned the old grease out of the shell. Then I applied ceramic grease to the mating surfaces and stuck them back in.
On my bike, it looked like there were two different generations of grease in there already.
(Step 4 of SRS Instructions) Grease the mating surfaces between the endcaps in the frame and the height adjustment bracket.
(Step 7 of Rebuild Kit Instructions) Place the beam back onto the frame, first by sliding the height adjustment bracket over the frame plugs, and setting the pivot bolt's head into the frame's pocket.
(Step 7 of Rebuild Kit Instructions) Align the holes of the eye bolt and the frame, and insert the pivot pin into the frame from the rider's right side with the non-serrated end leading. Tap it with a 5/32" punch until it intersects the eye bolt's head and both holes in the frame. Once again, light taps should be sufficient.
Once done, the beam should pivot up and down, with the height adjustment bracket providing some friction.
I tried to match the original insertion depth of the pin, which resulted in about 1/8" of the serrated (right) side protruding.
- Reinstall the height adjustment nut, bolt, and washers.
Per SRS Instructions, the ridges of washers should face inwards, and the rounded side of the washers should point downwards due to their taper.
- (Optional) Restore original beam height and saddle bracket configuration.
I don't know when the pivot assembly was last serviced on this bicycle, if at all. It's entirely possible that all of these parts are original, making them at least 23 years old with potentially tens of thousands of miles of service.
Pivot Bolt Wear
Some subtle deformation seen on the edge of the pivot bolt head's thru-hole.
I also noticed that the new bolt from Co-Motion Cycles doesn't have the same flat feature on the tip of the head as seen on the original.
Pivot Pin Wear
The pivot pin's surface is tarnished where it was in contact with the frame, as well as where the pivot bolt made contact. It does not appear to be deformed or bent.
Silicon Bronze Washer Wear
The beam's anti-friction plate slot has been stamped into the silicon bronze washer.
Steel Washer Wear
This washer sits between the nut and bronze washer. There is some marring where nut made contact.
Support Washer Wear
Similar to the silicon bronze washer, the bottom steel support washer got stamped by the eye bolt's head.
The 3D models and drawings of the Softride Rear Suspension components available on this page were drawn and modeled by me, using measurements taken with digital calipers and other potentially imprecise methods. Every model should be considered to be 95% accurate at best, but some - particularly those where I don't provide a drawing at all - are far less accurate and are only for illustrative purposes.
None of these models or drawings attempt capture design intentions or reflect actual manufacturing tolerances, processes, or material properties that make them work in this application. In some cases I've identified replacements for a given part; these were chosen using my best judgment, but are often not a full match to the original.
SRS Classic Beam Assembly
The Classic beam assembly is divided into three sub-assemblies, not including the beam and the hardware integrated into it.
Beam Pivot Assembly ("101 Assembly")
|Softride Part Number||146815|
|Also Known As||"101 pin"5, "pivot pin"6|
The diameter of the pin is not consistent across entire shank; some material appears to be displaced by the stamped serrations. This makes it impossible to drive it into the frame from the serrated end, at least without damaging the frame's holes.
|Softride Part Number||17482 56|
|Also Known As||"17-4 SS Rolled threaded eye bolt"5, "Eye Bolt"6|
|Replacement Part||Co-Motion Cycles # FP0666|
|Thread||1/4" x 28|
Steel Support Washer
|Softride Part Number||16748 56|
|Also Known As||"Pivot Bolt Bottom Steel Support Washer" 56|
|Replacement Part 7||McMaster-Carr #91525A323|
The drawing in SRS Instructions erroneously shows leader lines pointing to both this part and the threaded insert embedded in the carbon fiber.
Silicon Bronze Washer
|Softride Part Number||15765 56|
|Also Known As||"Pivot bolt silicon bronze washer" 56|
|Replacement Part 7||McMaster-Carr #93490A029|
|Softride Part Number||15764 56|
|Also Known As||"Pivot Bolt Steel Washer" 5|
|Replacement Part 7||McMaster-Carr #91525A323|
This part is erroneously omitted from the Rebuild Kit Instructions contents list.
|Softride Part Number||16254 56|
|Also Known As||"Pivot Nut" 5, "Pivot Bolt Nut" 6|
|Replacement Part 7||McMaster-Carr #94819A100|
|Thread||1/4" x 28|
The replacement part is not an exact match; the original may be 17-4 stainless steel like eye bolt. While working on my bike, I reused this part and did not replace it. With better searching, one may be able to find a 17-4 SS replacement.
Pivot Nut Retainer
|Softride Part Number||16048 56|
|Also Known As||"Pivot Nut Retainer"56|
This part is very conducive to 3D printing, so I've created an STL as well.
|Softride Part Number||15618 56|
|Also Known As||"Dust Cover"|
Beam Height Adjustment Assembly ("103 Height Adjustment Assembly")
Height Adjustment Bolt
|Softride Part Number||16917 6|
|Also Known As||"103 Height Adjustment Bolt" 6|
|Thread||M6 x 1.0|
Height Adjustment Washers
|Softride Part Number||16920 6|
|Also Known As||"103 Taper Washer" 6|
Height Adjustment Nut
|Softride Part Number||16918 6|
|Also Known As||"Height Adjustment Nut" 6|
|Thread||M6 x 1.0|
These parts are inserted into a shell of the frame's "top tube", A.K.A. the "102 Bracket"6. They are not shown in the 3D models of the beam assembly.
Left (Smaller Hole)
|Softride Part Number||16370 6|
|Also Known As||"102 OEM Endcap Left" 6|
Right (Larger Hole)
|Softride Part Number||16371 6|
|Also Known As||"102 OEM Endcap Right"|
Saddle Bracket Assembly ("Micro-Adjust 104 Seat Bracket")
Saddle Bracket Bolt
|Softride Part Number||21328 5, 23421 6|
|Also Known As||"6mm x 1 x 64mm Grd.10.8" 5, "6mm x 60mm LOHDSCS, Zinc" 6|
|Replacement Part 7||McMaster-Carr #91280A351 (Hex Head) or #92290A342 (SHCS)|
|Thread||M6 x 1.0|
It appears that this part was changed by Softride at some point, and their public-facing documentation wasn't updated consistently. On my bike, I replaced the original hex head bolt with a SHCS so I wouldn't have to carry a socket and driver for mid-ride adjustments.
Tapered Plug Caps
Left (Nut Pocket)
|Softride Part Number||19603 5|
|Also Known As||"104 Nut Cap" 5|
The drawing in SRS Instructions erroneously calls this part out as "104 Tapered Plug - 2 (19410)".
Right (Thru Hole)
|Softride Part Number||19604 56|
|Also Known As||"104 Molded Cap" 5, "104 Holed Cap" 6|
|Softride Part Number||19410 56|
|Also Known As||"Tapered Plug" 5, "104 Tapered Plug" 6|
Saddle Bracket Fasteners
|Softride Part Number||20218 56|
|Also Known As||"M5x.8 S.H. CapScrew" 6|
|Replacement Part||McMaster-Carr #92290A232|
|Thread||M5 x 0.8|
There are two variants of the saddle bracket part - one with tapped holes, and the other with counterbored holes. Aside from the fastener holes, these parts are identical.
On my bike, I swapped the left and right brackets to put all of the bolt heads on the drive side for easier mid-ride adjustments.
|Softride Part Number||21447 56|
|Also Known As||"Seat Mount Bracket" 5, "104 Seat Mount Bracket Counter Bored Side" 6|
|Softride Part Number||21448 5, 21447 6 (dubious)|
|Also Known As||"Seat Mount Bracket" 5, "104 Seat Mount Bracket Threaded Side" 6|
|Thread||M5 x 0.8|
The SRS Instructions lists this part as 21447, which is the part number of the counterbored bracket. I assume this is an error.
Saddle Bracket Nut
|Softride Part Number||19269 5|
|Also Known As||"104 Micro Adjust Flange Nut" 56|
|Replacement Part 7||McMaster-Carr #92773A101|
|Thread||M6 x 1.0|
A piece of the cast steel of my "nut pocket" Tapered Plug Cap cracked off its bottom / left side. I suspect this may have been caused by a flange nut that was slightly deeper than the original, and stresses from riding or tightening the bolt caused it to crack. I used JB Weld to glue it back together.
The nut was stuck inside the cap firmly. Because it had already cracked, I didn't dare try and remove the nut from the cap for photos or modeling.
The replacement nut I've specified may be too tight of a fit or too thick, and may pose a risk of cracking the cap in the same way. Modifications may be necessary to get the correct fit.
As of the time of writing, my maintenance job has held up for about 150 miles. Should anything go wrong with the parts I've chosen, or if I need to make any changes to my setup, I'll be sure to update this page.
As mentioned in the beam removal instructions, some photos were taken before I knew what I was doing. If I do this job again, I'll retake some photos so they all reflect the correct procedures.
3D Model and Drawing Resources
|Type||Name + Description|
SRS Classic beam 3D models and drawings
Height adjustment assembly 3D models and drawings
Pivot assembly 3D models and drawings
Saddle bracket assembly 3D models and drawings
Complete SRS Classic assembly
3D Model and Drawing Downloads
|Type||Filename + Description||Date||Size||SHA256|
All SRS Classic 3D models and drawings
"Upgrading an old Softride Powercurve, am I crazy?". The Paceline Forum. 2021-11-08. Retrieved July 2022. (Wayback Machine) ↩
"Softride Bikes: What is the deal with the bouncing?". Slowtwitch Forums. 2004-06-23. Retrieved July 2022. (Wayback Machine) ↩