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  1. #1
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    Geometry 29 fork on 27.5

    So I have a really nice 29 fork with 100mm of travel and thinking about switching to 27.5 FS (making the 29 full rigid) and thought if I bought a frame for 120mm geometry I could use the 29 fork without screwing up my geometry. Thoughts?

  2. #2
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    It should work. Going from a 27.5 fork to 29er fork should add about 25-30mm AC length. Overall, you're bringing the front end up an extra 5-10mm after you account for the extra 20mm fork travel, which isn't that bad. Especially if the 27.5 frame designed for 120mm fork starts with about a 68 head tube angle. If it's already slacked out at 66degrees or something, you might be pushing it.
    "a hundred travel books isn't worth one real trip"

  3. #3
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    Don't forget about the drop in wheel radius too.... but yeah, I'd rather have the travel.

  4. #4
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    Quote Originally Posted by d365 View Post
    Don't forget about the drop in wheel radius too.... but yeah, I'd rather have the travel.
    To clarify, my above statement is using a 27.5" wheel in a 29er fork. Probably want to make sure you have clearance for the intended tire around the 29" fork's arch support. Some forks bulge inward right where the 27.5" tires sit. Plenty of people run 27.5+ tires in 29er forks though, so it shouldn't be too big of an issue.
    "a hundred travel books isn't worth one real trip"

  5. #5
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    Thanks guys, I thought it would work, just wanted someone to check my math! Glad to hear others do it, I tried a search, but you know.....Google overload

  6. #6
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    I ran a 29er fork at 80mm travel on a 26" full suspension bike that started with a 100mm fork. The stock HT angle was 69 deg. It slacked the HT angle out to 68 deg, which was just about perfect.
    "a hundred travel books isn't worth one real trip"

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