18 September, 2007

A Mixte by Johnny


David originally ordered a Velo Orange 650B Randonneur frame for his wife. But as the months passed they decided that since most of her riding was in town, a mixte might be more appropriate. After many e-mails we arrived at this city/rando bike.

What's most interesting is that since there are no high quality mixte lugs available these days, it was decided to build the frame using half-lugs on the head tube. This is a difficult and time consuming combination of fillet brazing and lugged construction. I think Johnny did a magnificent job of it.

The other unusual feature is that Johnny Coast uses an oversized down tube on this very small frame and did not run the mid stays past the seat tube. This is the way he builds all his mixtes. Why not follow the example of the constructeurs? Because he feels this makes the bike laterally stiffer and lighter with little decrease in vertical compliance. Having examined some classic mixtes Johnny felt there was room for improvement.

There are more photos here.

19 comments:

  1. Sweet.

    That head tube takes a minute to get used to, but I really like the simplicity. I can't wait to see it built up.

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  2. It's like an inverse Singer-style headlug. Very cool bike.

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  3. I really like this bike. Clean. The headtube is gorgeous, rather like a reversed Singer. And of course Jonny's stay caps are maybe the nicest I've seen. Not French - maybe better. The headtube/stay transition is just sweet. Very nice.

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  4. Agree with everything above.

    Fantastic. I also thought "reverse Singer". Clean, simple, flowing lines, but some edges to catch the eye.

    Bravo.

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  5. Looks "right". Can't wait to see the photos of the finished bike.

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  6. Is the hole on the downtube for running a wire between a taillight and a generator hub (or the other way around: bottle generator to headlight)? If so, that's pretty cool; is there a similar hole near the bottom bracket?

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  7. which Johnny are you talking about?

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  8. hkfixed asked:
    which Johnny are you talking about?

    Johnny Coast of Coast Cycles
    http://www.coastouttabrooklyn.com/
    builds the Velo Orange Randonneur.

    --sfp

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  9. What's up with that lower headset cup?

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  10. BG, That's not a headset; it's a spacer that frame builders use to check fork fit.

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  11. I get the substitution of single for twin top tubes. Riv does the same. What I question is the need for three pairs of stays on the rear. If two pairs are ok for a normal bike, why would two pairs not hold up the back of a mixte? maybe the extra pair of stays is part of the genre like the twin top tubes . . . but I wonder how much of the tradition is based on old tube dimensions that are no longer relevant . . . I suspect you could make a better, lighter bike by taking advantage of modern tubes, but still retain much of the practical appeal of the design.

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  12. anonyme,
    the 'extra' stays serve to stregthen the seat tube: if the frame just had the dropped top tube, that tube would work to flex the seat tube backwards.
    the extra stays push forward against that backward force. thats one reason at least.

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  13. how can two attachment points for the extra stays be stiffer than 4? just curious. doesnt make any mechanical sense to me. (i know i can think of cases where 2 big points would be better than 4 little points, but that isnt the case here. Also, I dont really buy the lighter concept. maybe an once or two...

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  14. johnson,
    Maybe it's like when every few years someone tries to reinvent the wheel by resurrecting the oval chainring. Maybe Jonny's right and new materials have changed the rules, but them French fellas built a bunch of them the way they did for a reason. It is a great looking bike though.

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  15. sure, there's nothing prettier than an old French mixte. But I rode one for a while back then, and it wasn't a little heavier then my other bikes, but a lot. And it wasn't a little more flexible laterally, but a lot. So, I don't buy the argument that the old way was better; it wasn't. At least, not for riding. I still question the need for extra stays. "Girl's" style bikes of all sorts, all round the world, don't use them. The sturdiest Dutch bikes, which are mostly "Girl's" style, don't use them. Those bikes just drop the top tube--the Dutch bikes actually curve the top tube way, way down to touch the downtube, then arc it back up a bit where it meets the seat tube. There might be other reasons to use extra stays. One is the nice cable routing with centerpulls that some of those bikes have. Not much of a reason.

    just sayin.

    mw

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  16. i have a 70s peugeot mixte thats heavy not because its a mixte and has extra tubes, but because its straight gauge cheap steel, has steel rims, steel cranks and a steel seat post. however, i'm 185, regularly ride the bike as a commuter, and don't notice any more flex in the bike than is present with my XO-1. the difference seems to be more in handling than anything else. the peugeot isnt even a good mixte. the old custom mixtes used much better tubing and parts so the weight wasnt an issue, and i bet stiffness wasnt either. also, remember, most mixtes are still sold to women, so the rider is generally lighter...

    anyway...

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  17. this is some stunning work atmo -

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  18. Jonny gets it! nice work!
    -Eric

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