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  1. #1
    Senior Member Regulatori's Avatar
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    Fork: Axle to crown measurement. That is axle to bottom of fork crown, correct?

    Yes, another odd question from me. Just hit the back button if my threads make you clutch your pearls and stumble to your fainting couch.

    If you own a bike with a tight clearance between your tire and bottom of fork crown, would you mind giving me your axle to crown measurements?

    Looking at a few aftermarket track forks....
    3Rensho / TANGE Aero Front Fork
    Kalavinka / TANGE Straight Front Fork
    TANGE Front Fork with drilled brake hole for brake

    The axle to crown measurements in all of the track forks run in the 355-375mm range.


    When I converted my bike to threaded stem/lugged fork, the listed specs for fork to crown clearance was 350mm. After measuring, it's more around 353mm....close enough.


    Currently I'm running 28mm tires on Velocity Deep V's and figured it would be a very tight clearance between the tire/crown...I was kind of expecting rubbing issues. Instead I have a 3/4" or so.

    With 23mm Gatorskins, I have around an 1" of gap.

    Is that now common for track forks to have that much clearance? All of the track forks from Alex's Cycle above have larger axle to crown measurements so they'll have even a bigger gap.

    Yes...yes....just shut up and ride.

    Aesthetically, I always love how track bikes have that tiny seat tube/tire clearance combined with equally small tire to crown clearance.

    My bike (yes, the front wheel needs to be trued badly).
    Remember, these are with 28mm tires. With 23mm tires, I had about an inch of gap.







    What I expected....




    Most track forks have even a smaller gap.





    Just curious for people that have bought Soma track forks or any of the Japanese track forks from Alex's...is your setup looking like mine or the picture below?
    Samson track bike http://www.pedalroom.com/bike/samson-njs-ratalicious--28653
    Saddle was leveled using Hattori Hanzo handcrafted folded steel NJS certified spirit level

  2. #2
    Brown Jersey Winner Mumonkan's Avatar
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    if i remember correctly it is from the center of the axle to where the crown race sits
    Ride everything. Shave nothing.
    https://dirthurt.wordpress.com/ | www.pedalroom.com/members/Mumonkan

  3. #3
    Senior Member Regulatori's Avatar
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    When I bought my fork on ebay, it was only $45....guess it now went up in price.
    Here is the listing.
    http://www.ebay.com/itm/RH-O-Fok-932...p2047675.l2557

    It seems all of the listings are standard fork measurement listings...

    The complete length of the fork steerer tube is 250mm.
    The threaded portion is approximately 170mm.
    There is a 80mm gap between the fork crown and the bottom of the threads.
    The distance from the center of the axle to the brake hole is 355mm.
    The distance from the center of the axle to the bottom of the fork crown is 350mm.

    Width between dropouts is 100mm.

    You're telling me they're basically giving me a measurement (axle to crown) that no one else on the planet uses? And realistically, I needed to have added that whole crown section to the dimensions to get a true crown to axle measurment?
    Fuuuuuuuuuuuuu...I figured the bottom of the crown would be a more important measuring point because that would tell how you how much tire you can fit under there.

    IT was only $45ish but still...why would you create a fork with such a huge gap for 700C wheels??

    Pisses me off. Makes me want to get my multi-tool out and notch the fork ends higher up. hahaha The long fork ends is what makes this this fork so bloody long.
    Last edited by Regulatori; 01-04-16 at 08:36 AM.
    Samson track bike http://www.pedalroom.com/bike/samson-njs-ratalicious--28653
    Saddle was leveled using Hattori Hanzo handcrafted folded steel NJS certified spirit level

  4. #4
    Brown Jersey Winner Mumonkan's Avatar
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    Ride everything. Shave nothing.
    https://dirthurt.wordpress.com/ | www.pedalroom.com/members/Mumonkan

  5. #5
    Senior Member Regulatori's Avatar
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    Cool, solved that one.

    IS there a wheel size slightly larger than a 700C that would make a fork of my dimensions make more sense?

    I can't for the life of me remember how much gap my old 80's Ciocc had...maybe I've been looking at too many track porn threads and this is actually a standard gap.
    Samson track bike http://www.pedalroom.com/bike/samson-njs-ratalicious--28653
    Saddle was leveled using Hattori Hanzo handcrafted folded steel NJS certified spirit level

  6. #6
    Brown Jersey Winner Mumonkan's Avatar
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    27" wheel is slightly larger, but youre very limited with rim/tire choices

    but yes too much porn, youre starting to go blind. its pretty standard to have a good amount of clearance. ideally a bike ridden on the road should have at least 10mm of space on all sides for any potential debris.

    track bikes have clearances you can measure in the thickness of a sheet of paper because they are meant to be ridden on the boards, not alot of mud and stucks and pebbles going on there
    Ride everything. Shave nothing.
    https://dirthurt.wordpress.com/ | www.pedalroom.com/members/Mumonkan

  7. #7
    Ut In Omnibus Glorificetu TimothyH's Avatar
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    The Tange Aero (3Rensho replica) fork from Alex's is on my Bianchi. ACD on this fork is listed as 356mm. Wheels are Wabi Sub 15 and the inside rim width measured with a caliper is 18.2mm. Tires are Vittoria Rubino Pro III Slick 25's. Mine has much less space than yours. There is about 7 or 8mm clearance between the tire and fork crown, less than the thickness of a pencil. I chose this fork on purpose.

    In terms of looks I really wanted the straight blade Kalavinka fork from Alex's. ACD on this fork however, is listed as 375mm which is 19mm more than the Tange fork. That is what gave me pause. I can't remember being concerned about the look of the tire/crown clearance but I was concerned that a higher ACD would raise the front of the bike. I didn't want the top tube to look sloped but looks were secondary to my concerns about negatively impacting handling and the fact that I run short reach Dura Ace calipers (yes, brakes) and didn't want to have to get medium or long reach calipers.

    As near as I could tell, ACD on the Tange fork was almost identical to the stock Bianchi fork. The Kalavinka fork was almost 3/4 inch taller. Remember that ACD is measured from axle to the crown race seat.

    Edit: Just saw post #3 . Yeah, you have proportionately longer fork blades and shorter crown.







    -Tim-
    Last edited by TimothyH; 01-04-16 at 11:10 AM.
    http://atlantabikerides.blogspot.com/
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  8. #8
    Senior Member Regulatori's Avatar
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    Awesome post, thanks. My actual top hasn't change and there isn't any slope. The nerd in my actually put a 2 foot left on the top tube before and after and it reads the exact same. I even had a picture of the bike sitting in front of a garage shelf (the top tube was perfectly in line with the shelf)....after the change, I put the bike back in the same spot and saw no difference.

    Yeah, it's no big deal....I'll live with it. The main thing that threw me off was the measurements and the fact this ebay user used the bottom of the fork crown as opposed to the industry standard top.

    Your fork looks super sexy btw.
    Samson track bike http://www.pedalroom.com/bike/samson-njs-ratalicious--28653
    Saddle was leveled using Hattori Hanzo handcrafted folded steel NJS certified spirit level

  9. #9
    Senior Member SquidPuppet's Avatar
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    Quote Originally Posted by Regulatori View Post
    clutch your pearls and stumble to your fainting couch.
    This made my morning. Thanks.

  10. #10
    A Roadie Forever 79pmooney's Avatar
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    OP, I am going to guess part of what is driving the making of long track forks is the current fix gear craze. Marketing. The big clearance fork is better for the road, big tires and maybe even fenders. It wouldn't surprise me if the marketing guys' thinking was something along the lines of "Who are well selling $45 forks to? To folks who are going to ride the road and newbies to velodrome racing. There are far more road riders than velodrome riders and the road riders probably replace forks more often (as many ride without brakes in a world where everyone else, including every car has brakes whereas nobody has brakes at the velodrome)." Hence the market for forks at the $45 price range is skewed heavily to road riders.

    Just an observation: I see few of the better riders at the velodrome using steel forks at all. Almost all CF. When I see a national caliber rider at Portland's Alpenrose riding steel it is invariably because he rented/got loaned a bike and left his good bike at home instead of dealing with airports.

    Ben

  11. #11
    Senior Member Regulatori's Avatar
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    I'm tired and my Klonopin (prescription) is making me a bit loopy.

    BUT....could a frame/welding shop chop off a section of the fork end and weld the two existing pieces together?

    It doesn't look like much but that's 5/8" right there.

    I've been doing some reading and have across some insane stuff...like people taking multi-tools to their front suspension fork ends, carving a deeper channel, and then throwing it on their kid's bike to keep the geometry closer to stock.

    I know it's only a $40 fork but I have some friends at a few shops that owe me favors. Just curious if this could even be done...or would it be too an accident/wreck waiting to happen?

    Just a 1/2"-5/8" gap removed would be a huge improvement over that stupid crown/tire gap.

    Samson track bike http://www.pedalroom.com/bike/samson-njs-ratalicious--28653
    Saddle was leveled using Hattori Hanzo handcrafted folded steel NJS certified spirit level

  12. #12
    canis lupus familiaris rex615's Avatar
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    If the fork looks like the one on the left, and the fork ends are brazed, they could be "un-brazed" and set deeper onto the fork legs. In theory it could work without weakening them, but it takes skill with the torch. In reality it takes a lot heat to remove the fork ends, so it is easy to overheat the legs and weaken them.

    If the fork is chromed, that makes the job more difficult and heating it will damage the chrome finish.


    did you photoshop the "cut" from one photo?

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