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Swap out suspension fork for fixed?

Old 03-29-20, 09:03 AM
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steve-in-kville 
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Swap out suspension fork for fixed?

I've been out of the game for a while. I have a ten-year old Hardrock that I want to swap the front fork for a fixed fork. How do I go about finding a fork that would be geometrically correct? Thank you.
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Old 03-29-20, 09:07 AM
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Measure the axle to crown length. See you can find the specs for rake, trail or offset.
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Old 03-29-20, 02:01 PM
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Look at "suspension corrected" forks

https://surlybikes.com/uploads/downl...structions.pdf
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Old 04-01-20, 11:59 PM
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Also see CarbonCycles & SalsaCycles for more fork options.
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Old 04-03-20, 03:41 AM
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If you want handling to remain the same, measure the axle to crown distance (from the center of the dropout to the bottom of the lower headset cup) and shorten that value by about 20% (to account for sag) to find the correct A2C for your new fork. You can also look up the amount of rake on the fork, although there's not a ton of variety on replacement forks. Take note that you may like a slightly shorter A2C if you're using the bike to ride around town, as it'll make the steering quicker/less stable which is more road-bike-y.
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Old 04-03-20, 07:18 AM
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Originally Posted by cpach
If you want handling to remain the same, measure the axle to crown distance (from the center of the dropout to the bottom of the lower headset cup) and shorten that value by about 20% (to account for sag) to find the correct A2C for your new fork.
Wrong. To account for sag, you need to subtract ~20% of suspension fork travel from the A2C figure, not 20% of A2C. Or you could measure the sag directly (if the fork still works).
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Old 04-03-20, 07:41 PM
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Originally Posted by subgrade
Wrong. To account for sag, you need to subtract ~20% of suspension fork travel from the A2C figure, not 20% of A2C. Or you could measure the sag directly (if the fork still works).
That's what I get for posting late when I can't sleep!
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