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Swapping out Suntour XCM to rigid carbon fork

I have a Trek 3900 disc 26er hardtail that I use primarily for touring (yes really). The forks, Suntour XCM are ineffective and are just baggage. They are 1 1/8" straight tube with Avid BB7s.
I am considering swapping to an inexpensive rigid carbon fork.
Before I go ahead and purchase a set of generic Chinese carbon forks:
(1) are there any pre-purchase traps I should be aware of, and
(2) I assume I cut the new steerer tube exactly the same length as the existing one.
Thanks in advance


  • mully79mully79 Posts: 904
    Make sure theyre "suspension corrected" so the bike sits the same as before.
    Check calliper fitment ( you may need an adapter)
    You may not have to cut it. depends on steerer length but you may need more/less/thicker/thinner headset spacers.
  • flight996flight996 Posts: 15
    Thanks mully79
    Suspension corrected (check)
    Brake bosses (check)
    An extra spacer or two is a great idea. Lower back and scapular will love a more upright riding position.
  • careca78careca78 Posts: 102
    I did something similar with a Trek 8500 26in frame I got from warranty after cracking my Trek 6000 head tube (from having a WAAAAYYY longer fork than the original), and bought an Exotic aluminium fork, but this time geometry corrected...

    They also have carbon options, with straight steerer tubes, for discs and V-brakes, etc.

    Check their website:

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