Viewing 16 posts - 1 through 16 (of 16 total)
  • Through axles with a 1.25mm thread pitch
  • njee20
    Free Member

    I have broken the front through-axle (a crappy OEM Chinese one) on my winter road bike, I merrily ordered a Brand-X replacement, 12x100x1.5mm, only to find that it doesn’t fit, it appears that I have a 1.25mm thread pitch (on front and rear incidentally, but the front is more pressing). I can find a small handful of axles with a 1.0mm pitch, seems it’s more common on 15mm axles. My Google Fu is returning lots of “thru-axle nuts” with a 12×1.25mm pitch, which suggests it’s not completely unheard of, but I can’t find any actual axles. I’d ideally prefer an alley key one, but right now I’m not that fussed. Cheaper rather than expensive, given it’s only my winter bike, which I can’t now ride!

    swoosh
    Free Member

    I used the Wolftooth chart found on this page to work out what axles I needed for my 2 bikes. According to the chart there aren’t any with a 1.25mm pitch, are you sure that’s right?

    njee20
    Free Member

    Pretty certain, yep, and yes, that is the issue, it appears not to be a thing. I think it was in the early days of disc frames before stuff settled down.

    crossed
    Full Member

    https://robertaxleproject.com/

    These guys do pretty much every type of axle you can get. Not cheap though.
    I think SJS Cycles stock their stuff.

    njee20
    Free Member

    Yeah, it’s their print out ‘size guide’ that convinced me it’s definitely a 1.25mm pitch, as they don’t do them 😀

    damascus
    Free Member

    You might have to swop your forks over from another bike until you can find one. I don’t think I’ve seen a 1.25 before.

    What frame is it? What did the frame manufacturer say?

    njee20
    Free Member

    It’s a Chinese frame, DengFu. I’ve emailed them, will see what they say. New fork isn’t catastrophic, amazingly it looks like that’s probably the answer.

    I exchanged emails with the proprietor of “Vaaru” bikes, as they have a footnote that some early forks of theirs were 1.25mm pitch. He confirmed they’re really hard to get, and had bought up a load of stock from the manufacturer.

    paton
    Free Member

    Use a thread repair, Helicoil , thread insert M12 x 1.5 in dropout?

    njee20
    Free Member

    Cheers, interesting thought. Hadn’t thought of that. Not entirely sure it’s worth the effort!

    damascus
    Free Member

    @njee20

    Can you buy a rear axle and take it to an engineering company, chop it to size and get a 1. 25 thread put on?

    Or if you have a tap and die set do it yourself using the old one for measurements

    Or can you remove the thread from the fork and replace it with a different size?

    porter_jamie
    Full Member

    thats very fine for an aluminium bolt – got a pic?

    njee20
    Free Member

    Can you buy a rear axle and take it to an engineering company, chop it to size and get a 1. 25 thread put on?

    Or if you have a tap and die set do it yourself using the old one for measurements

    Or can you remove the thread from the fork and replace it with a different size?

    1 or 2 are great ideas actually. I wonder if the axles are a constant wall thickness. I suspect the Brand X one I’ve got is… I’ll have to check my dies, bet they only go up to 10mm!

    Can’t remove the insert, not sure I’m brave enough for drilling it an helicoiling it.

    thats very fine for an aluminium bolt – got a pic?

    Will take one.

    Deng Fu came back and confirmed that early frames did have a 1.25mm pitch, but they didn’t think they had any axles left. I’ve asked about a replacement fork. Looks like a Selcof one, which is probably the same product, is £100, so not catastrophic after 5 years use.

    njee20
    Free Member

    In the interest of rounding this out:

    thats very fine for an aluminium bolt – got a pic?

    Yes, 1.5 pitch one, measured against “The Robert Axle Project’s” sizing guide.

    [url=https://flic.kr/p/2mAYk5z]Thru axles[/url] by njee20, on Flickr

    Surprisingly difficult to photograph because of the angles, but you can see the LH side lines up with their guide.

    My one (does not line up, 11 threads versus 10 on the replacement):

    [url=https://flic.kr/p/2mB2HsN]Thru axles[/url] by njee20, on Flickr

    But I liked this:

    Or if you have a tap and die set do it yourself using the old one for measurements

    So job jobbed.

    [url=https://flic.kr/p/2mB3TS9]Thru axles[/url] by njee20, on Flickr

    Not perfect, but it’ll do. Goes in nice and smoothly.

    Quite want to do the back now as well, to get rid of the crappy QRs. That has a nut with the thread on the outside for the mech hanger and the inside for the axle, which again seems to make it hard to replace. Somewhat easier now things are standard! Thanks everyone for the help, particularly @damascus for the solution.

    damascus
    Free Member

    @njee20 nice job. You’ve identified a gap in the market. Get some more made and sold on eBay

    If I’d had one on ebay, how much would you have paid for that? £30? Could be a nice side line 😂

    njee20
    Free Member

    Haha, yes, I happily would actually! I may need a lathe to go into large scale production…

Viewing 16 posts - 1 through 16 (of 16 total)

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