Posted by: Brendan | February 2, 2011

Sprecher

The latest John Henry was inspired by some old ideas.

I’d taken a page from the 1950’s balloon tire bikes style book, and added a Sireny twist.

I had a few constraints to work with on this bike:
-relatively good standover clearance (Sirens have a tradition to uphold here)
-room for 3 large water bottles for long rides
-short chainstays
-dashing good looks

The design I settled on accomplished all. By mating the shallow bend twin top tubes to a seat mast, I was able to keep the standover clearance on this bike fairly close to that of the regular medium John Henry, while also maintaining room for the large bottles.
I also tried my hand with fillet brazing, which is new to me… turned out nice on the seat mast. Looking forward, I’d do it on all the top tube bridges on the next bike.


The seat mast design works to improve standover clearance, and also provides a nice hike-a-bike handle.

Mary worked up a special commemorative edition decal for this bike, celebrating my 20th year of riding mountain bikes/ working in the bike industry. Looking forward, we’ll be adding some more fun graphic designs to our frames.

I can’t get enough of the lines on this bike. The symmetry and the merging of the twins is just a beauty to behold.

The Ride

I had an opportunity to take her out for a good ride this past weekend, on a moderate bikepacking trip. I’d hypothesized the relatively shallow seatstay angle would give the bike a bit more vertical compliance. Additionally, the twin tubed design gives the same amount of tubular surface area as single top tube would… so, if anything the entire frame should have a more vertically compliant ride, albeit at the expense of less torsional stiffness. To some extent, the seat mast design should stiffen this up a bit, I figured.

Loaded up for an overnighter.
The bike felt great. If anything, my thinking about the torsional stiffness could be true.  My most recent bike was an aluminum frame, with great stiffness all around, the lively feel of this bike was very inviting and easy to get used to. The bike jives with twisty singletrack. If I were to build a similar bike for a larger/stronger rider, I’ve got a couple more ideas to add some stiffness if that were a concern.

Weight: She’s a bit heavier than a comparably sized John Henry. But for the added smoothness, and style, the weight was well worth it for me. As they say, fashion feels no pain.

 

 

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Responses

  1. I think this is one of the best looking bikes you have built. Love the twin top tubes.

  2. Looks beautiful, a real truimph. Well worth the effort and perseverance.

  3. Thanks Rhino. I’m proud of it and hope to evolve the idea further for my customers.
    And I forgot to mention, the name comes from my favorite brand of root beer, which we used to enjoy on college road ride stopovers at this place:
    http://www.rootbeersaloon.com/

  4. Thanks Ricky! I think we’d posted at the same time.

  5. Ok I want one! But what to do with my beloved John Henry then?

  6. I really love this frame, B. She’s a beaut.

  7. @ Weyland: Make your current John Henry the gearie… I think the twins lend themselves well to a clean, singlespeed aesthetic. I *almost* regret putting cable stops on Sprecher.

    @ Rick: Thanks. I totally dig the leftover powdercoat from your frame!

  8. nice work Brendan. did you build the bars as well?

  9. Brendan:

    I really like the looks of this frame. Exactly how short are the stays?

  10. @ John: Yes, I built the bars too. I’ve had them a while now and really like them. I’l be making a set for Mary before too long with an extra “hook” on the forward ends for a thumb grip. I call ’em Barney Bars.

    @ Eric: the stays are sub 17.25″ which to me is short, albeit maybe not in the “super short” realm. Plenty short for me to feel the agility on my techy-but-long rides.

  11. now that is sexy. and yes, what to do with my JH now? haha!

    any word on SRP? hehehe

  12. ever think of mounting the rear brake on the chainstay? not sure how that’d work with the sliding dropouts (it may also limit brake choice). maybe an EBB version?

  13. Agu… I don’t know what SRP is? Maybe I’m overlooking something obvious.

    As for the chainstay mounted caliper, yeah, I thought about that a bit too. Paragon also makes a swinging dropout that would maybe look nice on a bike like this. http://www.paragonmachineworks.com/storename/paragonmachineworks/Image-10748074.aspx

    Otherwise, an EBB setup would be easy peasy and look really good.

  14. Hey B

    Sorry about that…SRP = suggested retail price 🙂

  15. Ah, that kind of SRP.
    I figure it’s a John Henry + some extra custom work. Truthfully I built it without much regard for the fact that somebody else might want to buy one like it.
    But if you did… I’ve definitely got some ideas for improvement. 🙂

    • hmm tempting…let’s talk once you receive my JH (and the goodies). Jay will be sending it sometime next week!

  16. by golly – very tasty.

  17. […] We hung out on the pier for a bit enjoying some taffey and splitting a Sprecher Orange Dream Soda. (Check out the Siren bike named after Sprecher here.) We then made our way down the coast along the […]

  18. That is gorgeous. Did you get good clearance between the seat stays? Seems a bit tricky with the twin full length top tubes, without hitting tubes with your knees?

  19. Eel,
    The tire clearance is more than adequate for a Saguaro or a 2.4″ Racing Ralph. The top tubes curve in together as they intersect at the head tube, so there’s been zero knee clearance issues as well. Part of this balance comes from the lower point of intersection along the seat tube compared to other twin top tube designs.


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