120mm vs 100mm
07-18-18, 09:22 PM
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120mm vs 100mm
What provides the best all around performance for cross country suspension ; 100mm of travel or 120mm?
Last edited by SoldSpartan; 07-18-18 at 09:51 PM.
07-19-18, 05:59 AM
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07-19-18, 12:51 PM
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Kind of a vague question considering we don't know what type of "cross country" you are riding. I have a 2 bikes..One with 100 and the other with 120. The 120 is much nicer
07-20-18, 10:29 PM
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Which fork better fits the geometry of the bike you want it on?
What's your idea of a good time on the bike?
Where do you live and which trails do you ride?
These questions will answer your question.
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Still stupid and seriously neglected..
Still stupid and seriously neglected..
02-07-20, 08:37 AM
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is there really much difference between the two?
02-07-20, 01:21 PM
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kinda like down-east Maine which is kinda up by the northern part of Maine, yes, it's more east, but come on on it's only "down" from Canada! 
02-07-20, 04:17 PM
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You actually can "over-fork" a bike. This is if the bike's geo was designed for a 100mm. A friend put a 120mm on his that originally came with a 100mm. He lost a climbing efficiency but felt better on the downs. Are all bikes this sensitive to change, no. Another guy I know did the same to his, plus converted to 27.5 from 26. He ruined that bike--way too upright and has no standover now. He should've left it 100mm with the wheel upsize.
02-07-20, 04:23 PM
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No, just 20mm 
Adding 20mm more will rake-out the geo some and slow the steering of the bike somewhat. Also puts the rider in a more upright position. 20mm might help a tad when landing mild air but 20mm is not enough at the 100-120mm range to help like riding a 130-140mm bike. Putting the latter on a bike designed for only 100mm will mess up the bike's handling, especially climbing steeper, techy stuff.
Adding 20mm more will rake-out the geo some and slow the steering of the bike somewhat. Also puts the rider in a more upright position. 20mm might help a tad when landing mild air but 20mm is not enough at the 100-120mm range to help like riding a 130-140mm bike. Putting the latter on a bike designed for only 100mm will mess up the bike's handling, especially climbing steeper, techy stuff.
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02-07-20, 04:28 PM
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Both are good for XC, depends on the geo designed into the bike. Many newer XC bikes have 120mm but the geo is adjusted to keep the climbing nice. 120mm might allow one to jump off slightly higher stuff than a 100mm. Neither are design to launch off big stuff like a 130mm, 140mm or longer travel.
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02-07-20, 06:20 PM
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I over forked a rigid single speed with a 120mm travel fork (bike is badass now).
yes the geometry changes a bit
yes the geometry changes a bit
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02-08-20, 08:52 AM
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I've had two bikes with basically the same fork (Rockshok Recon) in 100, and 120mm. I prefer 120.
It could also be the 120mm fork is on an all around better bike too.
It could also be the 120mm fork is on an all around better bike too.
02-08-20, 12:33 PM
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what are you doing exactly upgrading a fork? what do you have now bike and fork?
02-08-20, 08:49 PM
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The OP has not even said if he means a HT or FS
I would go with 120, because it is 20 more than 100. Its like having 100, and 20 more.
I would go with 120, because it is 20 more than 100. Its like having 100, and 20 more.
02-10-20, 09:14 AM
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02-11-20, 09:35 PM
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All ya all are wrong. 50 to 60 mm is enough for all around. Just like 26ers do the job. 
02-12-20, 06:23 AM
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Banned.
