Building - Challenge Seiran headset

Print Page | Close Window

Challenge Seiran headset

Printed From: BHPC Forum
Category: Public: Open to anyone
Forum Name: Building
Forum Description: Anything to do with building HPVs
URL: https://forum.bhpc.org.uk/forum_posts.asp?TID=7842
Printed Date: 26 March 2026 at 10:38pm
Software Version: Web Wiz Forums 12.07 - https://www.webwizforums.com

Topic: Challenge Seiran headset

Posted By: AndyW
Subject: Challenge Seiran headset
Date Posted: 09 November 2025 at 2:53pm

Hi, I own a Challenge Seiran with USS, and I've recently discovered that the headset is threadless and, in the absence of a stem or any kind of clamp, there is nothing holding the forks in except the star fangled nut and the top cap bolt. Having checked out photos of other Seirans, including on the (still existant!) Challenge website, this looks to be standard; the bike handles fine and, in the five months I've had it, the headset hasn't loosened (unlike the one on my upright road bike...).
I have two questions:

is this indeed standard for this bike?

should I be worried?

Any answers or other thoughts on this would be gratefully received.