I needed to replace my broken Bontrager Satellite Plus carbon/aluminum fork on my '05 Trek 1000. I chose this Q2 carbon/ aluminum fork
as a replacement because the few Satellite Plus forks I was able to find online had their steerers cut too short or were unacceptably marred for the asking price.
The unforeseen problem with this Q2 fork is that the crown seat is larger by 5 mm than the current lower headset, an Aheadset semi integrated, and therefore sticks out ridiculously past the the circumference of the lower head tube. See photo. What can be done to better mesh the new fork's crown to the head tube of the Trek?
I've been reviewing headsets and the SHIS system but I can't seem to hook up what is needed here. Will a "conversion " crown race work? What exactly (in SHIS nomenclature) do I need if replacing the entire lower headset is the best option? Lastly, is the crown seat diameter commonly expressed --perhaps termed something different--in the sales information of a bicycle fork? This was quite the oversight on my part having paid particular attention to steerer length, axle to crown, and the rake figures when choosing from the pool of 700c, rigid road forks.
According to Sheldon Brown, the crown seat can be milled down to proper size. However, I could never get comfortable with the idea of tearing into that beautiful clear coat, let alone riding on a reshaped fork, so this is not an option here.
Some numbers (in the "for what it's worth" column). All are millimeters.
- 46.6 new fork's crown race seat diameter.
- 41 old fork c.r.s.
- 42 OD lower headtube.
- 37.6 OD Current crown race (a 30 ID) taken off the old fork.
Looking down the head tube with the new fork slipped in. Crown race not installed but current race would have no coverage beyond the current lower headset].