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Changing front fork to rigid one

Old 10-20-20, 10:38 AM
  #1  
brasio
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Changing front fork to rigid one

Hi,
I would like to change my front suspension fork with a rigid one. Fork is a RockShox Recon TK Coil - 100mm, and the bike is a Kona Shield 2019. Which parameters do I need to consider? Would you suggest me any models?
Thanks for your help
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Old 10-20-20, 10:52 AM
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Have a look at Smokinapankake post in C&V about his grail bike. It's a good, succinct description of swapping out a suspension fork for rigid fork.
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Old 10-20-20, 11:13 AM
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Originally Posted by brasio View Post
Which parameters do I need to consider?
Crown-to axle length, fork offset, steering tube dimensions, wheel size, tire clearance.
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Old 10-20-20, 11:21 AM
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I did such a conversion this summer. In addition to a rigid fork I also wanted to reduce weight of the bike (I used a Carbon fork and saved over 4 pounds), reduce wheel base and raise my bars. The key measurements are the ones that Rolla notes above. The swap-out took just a few minutes after I committed to the steering tube length. The swap transformed the bike from something I really hated to a good gravel/single-track bike.
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Old 10-22-20, 06:57 AM
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It seems very difficult to me to find a rigid fork: crown to axle is 506 mm, 51mm offset and a tapered steerer tube
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Old 10-22-20, 10:13 AM
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https://www.somafab.com/archives/pro...axle-crmo-fork
Assuming 25% sag, the axle to crown would be 506 - 25 = 481 -- about right.
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Old 10-22-20, 01:08 PM
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Thanks. It is not clear to me the concept of sag, however. Is it the default reduction of a suspended fork while just sitting on a bike? (that's why it is important to reduce the Crown-to axle length, while switching to a rigid fork, in order to replicate the real fork length).
25: is it a standard, well accepted value?
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Old 10-22-20, 01:17 PM
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Originally Posted by brasio View Post
25: is it a standard, well accepted value?
Yes, 25% of travel is a normal starting point for setting sag.
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Old 10-22-20, 01:22 PM
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You can also find conversion crowns. That is what I used on a conversion to a rigid fork.
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Old 10-22-20, 01:55 PM
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typical rigid fork for a 29er designed around a 100mm suspension fork is a 480mm or so axle-crown. Surly, Soma, Salsa, and Kona make some good cheaper options for you there. Check out the Kona deals on Bikeman.com. Carver and a huge array of more expensive carbon fiber options are out there too.

if your old fork has a tapered steerer tube, you can replace the fork with a straight steerer tube if you can also replace the headset crown race with a step-down version. most headsets have this option available.
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Old 10-23-20, 01:55 AM
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Should fork offset vary too or it must be exactly the same (in my case 51mm)?
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