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  1. #1
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    Axle to crown on Moment

    On Ellsworth's website it gives the axle to crown length of the Moment as 22 inches (559 mm) to get the 68 degree headtube angle that the Moment has. I have a Lyrik fork on my Moment, which has an axle to crown length of 545 mm. I read that a 20mm change to the a/c length is about one degree difference. That would mean that my fork has a 68.7ish degree headtube angle (14/20 + 68). Am I understanding this right?

    I'm just curious. I never really thought about the a/c length when buying a fork. Even so, there don't appear to be any 160 mm forks with 559 mm a/c length, which makes me wonder why Ellsworth is using 559 mm when giving measuring the geometry of the bike.

  2. #2
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    Quote Originally Posted by LowLow View Post
    On Ellsworth's website it gives the axle to crown length of the Moment as 22 inches (559 mm) to get the 68 degree headtube angle that the Moment has. I have a Lyrik fork on my Moment, which has an axle to crown length of 545 mm. I read that a 20mm change to the a/c length is about one degree difference. That would mean that my fork has a 68.7ish degree headtube angle (14/20 + 68). Am I understanding this right?

    I'm just curious. I never really thought about the a/c length when buying a fork. Even so, there don't appear to be any 160 mm forks with 559 mm a/c length, which makes me wonder why Ellsworth is using 559 mm when giving measuring the geometry of the bike.
    I asked freeborn the same question. They said its not axle crown thats quoted , it's fork length, ie the height if you stood them on the floor and measured from the floor to the bottom of the steerer tube. If you measure that on a 160 mm fork its about 15mm more ie 560mm or 22 inches.

  3. #3
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    Quote Originally Posted by Nsynk View Post
    I asked freeborn the same question. They said its not axle crown thats quoted , it's fork length, ie the height if you stood them on the floor and measured from the floor to the bottom of the steerer tube. If you measure that on a 160 mm fork its about 15mm more ie 560mm or 22 inches.
    Thanks, Nsynk. Seems like an odd way of measuring things. In fact, if you do a Google search for "static fork length" (in quotes), almost all of the results are related to Ellsworth bikes. I wonder why they don't just give you the a/c length like everyone else...

    I've been trying to figure out a way to slacken the head tube angle of my Moment by a degree, but haven't come up with anything. I thought about getting an Angleset, but I only have the 1 1/8" steerer tube. I also have been thinking about getting a 650b front wheel, but don't want to spend the money to have it built until I see that it actually fits, but I haven't been able to find anyone to lend me a front wheel, and it's rare that you find anyone selling stock 650b wheels. Oh well, I'll just go polish the rockers...

  4. #4
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    Low low I have an ofanaim head angle set in my rogue. It's 11/8th specific. Think the website is www.ofanaim.org . It's in Hebrew but google will translate it. I ordered mine through the website and it arrived a few days later. Fitting was fiddly but once fitted it has run smoothly for 2 years now.

    I also have burgtech offset bushings. Again ordered on line. These "fool." the geometry by making the shock appear to have a shorter eye to eye, thereby slackening the angles and lowering the bb.
    Both these fixes are possible on the moment.

  5. #5
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    The website I ordered from was Ofanaim.net and the owner is mtbr forum member saar g7 . You could private message him.

  6. #6
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    Oh and one other option. Years ago I bought an orange patriot lt. The shock was 190 x 57 . A non standard size. That would slacken the geo without losing travel. There may be a few still around, mine is a fox vanilla .
    I have also contacted elka about making a non standard eye to eye shock and they said they could produce them.. Although that was for the rogue so a longer eye to eye than you would be needing but they may be able to produce a 190 x57
    Lots of options!!!

  7. #7
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    Thanks for all of that information. I'm going to look into these options. The bushings seem like the most cost-effective option...

  8. #8
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    Quote Originally Posted by LowLow View Post
    Thanks for all of that information. I'm going to look into these options. The bushings seem like the most cost-effective option...
    Yes the bushing option is probably the cheapest. One thing to consider.
    With an angle set you slacken the fork angle but the frame angles steepen .
    Ie the seat tube will steepen a degree. That's good for climbing of course but shortens
    The effective top tube plus the bars are physically closer again a shorter effective top tube.

    With offset bushings the whole front triangle slackens . So the seat angle is slacker too.
    Not as good for climbing but the effective top tube lengthens .
    In terms of stack and reach though you get less reach as your further along the top tube relative to the bb.
    All this means think about the whole geometry effects not just the head angle. Make sure you will be happy for the whole ride. Descending is perhaps only 1/3rd of a ride.

  9. #9
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    Quote Originally Posted by Nsynk View Post
    Yes the bushing option is probably the cheapest. One thing to consider.
    With an angle set you slacken the fork angle but the frame angles steepen .
    Ie the seat tube will steepen a degree. That's good for climbing of course but shortens
    The effective top tube plus the bars are physically closer again a shorter effective top tube.

    With offset bushings the whole front triangle slackens . So the seat angle is slacker too.
    Not as good for climbing but the effective top tube lengthens .
    In terms of stack and reach though you get less reach as your further along the top tube relative to the bb.
    All this means think about the whole geometry effects not just the head angle. Make sure you will be happy for the whole ride. Descending is perhaps only 1/3rd of a ride.
    I was actually just looking at posts and articles online about the downside of using bushings, so your post is very helpful.

    A few questions, if you're motivated: I understand why the effective top tube gets shorter when you slacken the head tube angle, but don't really understand why it changes the angles of the seat tube. Don't the anglesets just change the angle of the steerer tube coming through the head tube? If so, why does that affect the seat tube? Or do you mean that it's effectively steepening the seat tube angle because it brings the top tube closer?

    So I contacted the Ofainem person, and he was nice enough to recommend Works Components if I just want to slacken the angle 1 degree. That's what I'm thinking about doing. Do you think 1 degree is slack enough, or do you think I should go 1.5 degrees?

    Thanks again.

  10. #10
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    Think about it like a pair of scissors . If you put one point on a surface then open up the scissors the angle of both blades changes.. So with the bike the back wheel is the fixed point ,as you pull the front wheel forward by slackening the forks angle it's like opening the scissor blades , the frame tips forward . It actually gives another big advantage as the bb gets lowered . About 1/4inch per degree . All ells have relatively high bb's so it brings that part if the geo to a more modern standard.

    I had a moment sst1 for a while. I used a shorter eye to eye shock in it and slackened the angles by 1 degree . It handled brilliantly . If you are looking for maximum downhill stability then slacker is better and lowering the bb improves the cornering. However there is always a compromise and in this case it's the climbing and slow speed handling .

    One thing I would not recommend though is using a long stem to get some of the climbing ability back . Seems pointless to improve the handling by slackening the angles then compromise it with a long stem.
    Last edited by Nsynk; 10-13-2012 at 02:20 AM.

  11. #11
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    Just thought I'd follow-up on my efforts to slacken my Moment. I ended up getting a 1 degree offset headset from Works Components, which I guess slackens the bike to 67 degrees. It's not a huge difference, but it's noticeable, and I like it so far. The bike definitely feels more stable, but that's also because I put on 740mm handlebars (from 680mm) and shortened the stem to 60mm from 70mm. I don't think any of this really affected the climbing capability, but I'm not a serious climber.

    I want to try out a 50mm stem to see how it feels, but I'll wait for a while to see how I like the 60mm stem. I bought a cheap Hussefelt stem to replace my Thomson one. Man, that Thomson stem is so much nicer looking and lighter. The Hussefelt is a real pig, but only cost $18.

    On another note, I demo'd a 2013 Specialized Enduro. I was surprised at how cramped the cockpit felt compared to the Ellsworth, even though I ride a medium Moment and the Enduro was a large. Anyway, riding the Enduro made me want to hold on to my Moment a while longer...
    Last edited by LowLow; 11-19-2012 at 02:08 PM.

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