I have about the same wheels as you although mine are 50/55mm. 3.1 carbon spokes, 20/20.

I am about 78kg.

I just tried the deflection test and can't get it anywhere near the stay. Maybe 2mm of movement, max.

My wheels are quite stiff in a sprint. My sprint power is just shy of 1400 watts and I don't feel anything I would describe as flex in the rear.

My frame is a Speeder 55d size 510, or Medium.

I wanted to share my experience with a set of ZEN 60/55 lightweight rims and hopefully get some input from riders with similar specs.

First off, credit where it’s due: ZEN has handled everything so far in a very professional and supportive way. Every time an issue came up, they responded accordingly and covered the costs to resolve it. That level of service deserves recognition.

Background / setup:
- ZEN 60/55 lightweight rims
- 24mm internal width
- SR270 hub
- 20x 3.1mm (2.1gr) carbon spokes (front & rear)
- System weight limit: 135kg
- Rider: 85kg, FTP ~340W, sprint ~1300W
- Tires: 30mm road + occasionally 38mm gravel (on a frame rated max 38mm)

Initial issue:
After the first rides, I noticed the rear drive-side spokes rotating (bladed spokes losing alignment). ZEN offered to cover a local rebuild/straightening -> great service. Unfortunately, the issue came back twice.

At that point, I suspected the spoke–hub interface might be the root cause (spokes rotating under load). ZEN agreed and sent a new hub + T-head spokes to eliminate that variable. Again, fully covered.

Current situation:
With the new setup, the spoke rotation issue seems resolved. However, under high load (especially sprinting), I’m now noticing:

- Audible movement/“working” from the rear wheel
- Tire rubbing the chainstay (this was already the case with the original spokes)
- Overall feeling of flex under power (this was already the case with the original spokes)

Given my weight and power numbers, I’m starting to question whether this wheel configuration is simply too light / not stiff enough for more aggressive riding.

What I’m trying to figure out:

- Are other riders (~80–90kg, similar power) experiencing comparable flex with lightweight carbon-spoke setups?
- Is this a known limitation of this kind of build (low spoke count + carbon spokes)?
- Or does this still point to something being off in my specific rear wheel?

To be clear: this is not a complaint about ZEN’s service, they’ve been excellent throughout. I’m mainly trying to understand whether I’m running into a design limitation versus a product-specific issue.

If others with similar rider profiles have experience with this type of wheel (especially carbon spokes / low spoke count), I’d really appreciate your input.

I never win anything, but I'd like to win this!

I'm curious about the decals (specifically the fact carbon sticker) Did you specify that you wanted that or did they default to it?

Frame finally showed up. Looks good to me!

Has anyone built one of these up recently? I’m curious about your experience and where you ordered from.

Also, I’m 178cm tall with an 82.5cm inseam. Is large or medium the way to go?

Thanks!

Hi all,

New member here. I ordered a 918 in early April, so hopefully I should have it in my hands soon, and really excited.

I only have a few concerns, but I have a technical brain so I should be able to work them out.

1) I run a 40t chainring. On my current Bianchi I have to run spacers to make it work, so it's just a case of how many on the 918.
2) I've also bought a set of the XC14 bars. The concern with these is that I run 720mm bars for XC, so it's a case of whether that will work for the internal routing (I'm guessing not).

The big challenge I've got is getting it under 10kg, but where there's money there's a way.

I'll be sure to post pictures when it arrives.

Did you order the new model with the trunion mount shock? How much was the total? What’s the build plan to get it under 10kg?

Last Saturday I put the bike to test during one of Europe's biggest gravel events, The Traka in Girona, Spain. First time for me and joined the 200km route with 2500m elevation. Bike got some serious beating and did not let me down, it's still in one piece! 

https://www.thetraka.com/

What size tires are you running?

Adding on to my questions:

Does anyone know if the trail mixer brake adapter is required to run the front fork in the forward position as it is on the Aspero?