Old 06-02-21, 12:44 PM
Junior Member
Join Date: Sep 2020
Posts: 17
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 3 Times in 3 Posts
Brand New Ultegra 8050 Drivetrain Pulsing and Noisy [Video of Problem]

*Video links at the bottom to hear the noise*

I recently built up my first bike from a bare frame (2020 - Trek Speed Concept). The drivetrain is Ultegra Di2 8050, with the exception of the chain which is Dura-Ace. The frame and all components were bought/installed new.

The drivetrain just seems noisier then it should be (the overall noise and kind of a clicking, and at times there is a pulsing or vibrating that I can feel in the drivetrain/pedals); this is in comparison to an older Cervelo R3 I have which has Ultegra 8000 mechanical drive train. The bike shifts crisply, but Iíd like to identify and eliminate the noise. Iíve ridden the bike approximately 500 miles, the bike has never been dropped or damaged.

I initially thought the noise could have something to do with my Zipp 404ís, which seemed to make more noise then a pair of Ican wheels (see videos below), but when I put the bike on a trainer, I get much of the same noise and feeling. With the Zippís on, the noise and pulsing seems most prevalent in the smallest cog and large chain ring. The noise is less pronounced in the same gear combination with the Ican wheels on. On the trainer, the noise is most pronounced when the bike is in the largest chain ring and 2nd to the largest cog (so almost cross chained). On the trainer, when I shift to the small chain ring and middle cog, the bike is at the noise level I would expect (quiet) and there is no pulsing feeling.

Iím no bike mechanic (I've been learning as I go), but Iívetried a few things to diagnose the issue, and now Iím at a loss for what to try next:


-Lubed and cleaned the chain (a couple times)

-Double checked the chain size (it was accurately sized according to Park Tools Youtube video on how to size a chain). I also tried a chain that was two links shorter. Same issue.

-I Have tried 3 different cassettes (on two different sets of wheels and a trainer).

-Checked the torque on the cassettes.

-Removed the chain to check for any sounds or play in the bottom bracket; felt smooth and no play

-Removed the chain and checked the jocky wheels, spun freely

-Initially thinking the Zipp wheel was the issue, I pulled it apart, bearings seemed good, wheel is true, and dishing is not dead center, but within 1mm, which I understand to be within tolerance.

Video of bike on trainer (at about 12 seconds the sound is most pronounced and at 23 second the shifting brings the sound to what I consider to be a normal level):

Video of sound with Zipp wheel on:

Video of sound with Ican wheel on (same gears as Zipp):

Any thoughts or suggestions are appreciated!

Last edited by rdiggidy; 06-03-21 at 10:20 AM. Reason: Update Title
rdiggidy is offline