Fork offset confuse...
 

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[Closed] Fork offset confused

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I’ve read through a few of the articles on offset and am thoroughly confused!

I’ve got a 2018 Reign with a 46mm offset Lyrik and looking to change to a Fox 36 which I think has a 44mm offset.

So I guess by going from 46mm to 44mm offset I’m reducing my offset, and presumably also reducing my wheelbase. I think I read somewhere that this will result in the Bike being more stable which is the opposite of what I would have thought.

Could someone please clear it up for me, what changes in handling will happen if I do this?


 
Posted : 29/08/2019 7:07 pm
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2mm change? I’d be surprised if you could tell the difference.


 
Posted : 29/08/2019 7:24 pm
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You won't notice a 2mm offset change


 
Posted : 29/08/2019 7:26 pm
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The trail figure is what dictates the steering response/stability.

Trail = distance the tyre’s contact patch sits behind a line extended down the steering axis to the ground.
As a result both head angle and fork offset affect the trail figure - steeper head angles make for a smaller trail figure, as do larger offsets. (I also found this counter intuitive initially).

The smaller the trail figure, the faster the steering. The larger the trail figure, the greater the stability.

All that said, you’re highly unlikely to feel a difference in a 2mm change in trail figure.


 
Posted : 29/08/2019 7:26 pm
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Often with these things it’s better to be blissfully ignorant. Humans are amazingly adaptable. If your new fork feels different to your old you’ll get used to it and adapt. It certainly won’t be a reason for any shortfalls in your biking skills. You might like to blame it but you’ll be clutching at straws.


 
Posted : 29/08/2019 7:42 pm
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I do tend to notice small changes.

Can someone please let me know - what change will this make?


 
Posted : 29/08/2019 7:50 pm
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It will slow the steering/increase the stability.


 
Posted : 29/08/2019 7:51 pm
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But only by an unperciptible amount. And for all you know, a difference in axle to crown may have the opposite effect so you might no actual change. You can put it all on excel and use an online calculator to check.


 
Posted : 29/08/2019 8:37 pm
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“I do tend to notice small changes.

Can someone please let me know – what change will this make?”

If the axle to crown length is the same, and the sag, and the dynamic ride height (which it won’t be) then it’ll be similar to slackening your head angle by just under a third of a degree. That’s like running 7mm less sag or higher dynamic ride height, so about 4% less sag.

You might notice it but few would. You won’t notice the change in front centre or wheelbase.


 
Posted : 29/08/2019 8:51 pm
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Thanks for clearing it up for me.

If it’s similar to slackening the head angle by a very small amount then I can definitely live with that


 
Posted : 29/08/2019 10:00 pm
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If mm matter so much then more offset lowers the front and steepens the head angle. A tiny bit.


 
Posted : 30/08/2019 8:53 am
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I used this when choosing my new forks. http://yojimg.net/bike/web_tools/trailcalc.php


 
Posted : 30/08/2019 3:05 pm

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