Going from a suspension to rigid fork...help with bearings?
03-29-20, 07:17 PM
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Going from a suspension to rigid fork...help with bearings?
It's been a while since I've put a head tube together, but know I need a cup to be pressed into the replacement fork. Going to be a surly fork (probably ogre, but maybe 27.5 ecr) - straight, so it's going to be significantly narrower than the current fork and bottom of the head tube.
So the bottom line: Will I need to replace the bottom of the head tube also, or just add a cup to the new fork, and get the right size bearing?
So the bottom line: Will I need to replace the bottom of the head tube also, or just add a cup to the new fork, and get the right size bearing?
03-30-20, 05:42 PM
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It's the other way around, cup on the lower head tube and a headset race on the fork steerer. Just look at a headset diagram on the web like cane Creek.
03-31-20, 12:27 AM
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Thanks, yeah, same difference.
i haven't taken the old fork off, but it's a very good possibility it's a straight fork anyway, so even better.
On a related subject, Surly recommended getting a fork length ~10% shorter than the fully unsprung length of the suspension fork. That would put me at a bridge club fork vs an ogre/ecr.
But I'm still heading towards Ogre at 5% less.
Any thoughts on length?
i haven't taken the old fork off, but it's a very good possibility it's a straight fork anyway, so even better.
On a related subject, Surly recommended getting a fork length ~10% shorter than the fully unsprung length of the suspension fork. That would put me at a bridge club fork vs an ogre/ecr.
But I'm still heading towards Ogre at 5% less.
Any thoughts on length?
03-31-20, 12:40 AM
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And sag is usually recommended to be considerably more than 10%.
The sus-to-rigid swaps I’ve made, I’ve always aimed for the sagged height, or shorter.
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03-31-20, 05:50 AM
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Thanks, yeah, same difference.
i haven't taken the old fork off, but it's a very good possibility it's a straight fork anyway, so even better.
On a related subject, Surly recommended getting a fork length ~10% shorter than the fully unsprung length of the suspension fork. That would put me at a bridge club fork vs an ogre/ecr.
But I'm still heading towards Ogre at 5% less.
Any thoughts on length?
i haven't taken the old fork off, but it's a very good possibility it's a straight fork anyway, so even better.
On a related subject, Surly recommended getting a fork length ~10% shorter than the fully unsprung length of the suspension fork. That would put me at a bridge club fork vs an ogre/ecr.
But I'm still heading towards Ogre at 5% less.
Any thoughts on length?
04-01-20, 08:56 AM
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The rule of thumb I have always heard is 25% sagged.
You are going to need a conversion headset, it sounds like
You are going to need a conversion headset, it sounds like
04-02-20, 12:44 AM
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25% of the travel is like 1.25 in or 30mm for most hard tails today. 10% of the fork length is like 50mm or two inches. So there’s a disconnect somewhere.
while this does change the geometry, it’s not going to explode and kill you if you get it wrong.
while this does change the geometry, it’s not going to explode and kill you if you get it wrong.
Last edited by Darth Lefty; 04-02-20 at 12:50 AM.
04-05-20, 08:10 PM
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The ogre and ecr are identical, except some versions of the ogre have canti mounts.
And I ended up getting ~40 cm shorter, which is only about 5% of the overall axlebto crown length, but 25% 5if there total fork range of travel, so it's right in the where it should be based on above.
Surly rep meant 10-20% of sag; believe I misunderstood what he was saying, and paraphrased incorrectly.
I also pinged Cannondale find out what headset bearings they use, but haven't heard back yet.
And I ended up getting ~40 cm shorter, which is only about 5% of the overall axlebto crown length, but 25% 5if there total fork range of travel, so it's right in the where it should be based on above.
Surly rep meant 10-20% of sag; believe I misunderstood what he was saying, and paraphrased incorrectly.
I also pinged Cannondale find out what headset bearings they use, but haven't heard back yet.
