Category Archives: bicycle frame building

Rivendell Appaloosa

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Photo courtesy of Rivendell Bicycles Works https://www.rivbike.com/

I recently ordered this lovely 2018 Rivendell Appaloosa frame.  It is designed for 650b wheels (a 51 cm frame) and has 135 mm rear spacing.

Why?  I have many wonderful bikes that I thoroughly enjoy riding.  But one thing I have never had since 1999 is a bicycle soul mate – that’s the year I crashed my 1976 Centurion Pro Tour.  Since then, while I have ridden many excellent bikes, I have never found that one bike that speaks to me, a bike that will take me into the next decades of riding, with comfort, competence, and a spiritual connection that is hard to explain.

In 2012 I built a 650b frameset while attending UBI’s frame building class here in Portland.  That experience helped me realize two things:  experienced frame builders have much knowledge and lore that newbies should respect and value. And, many cycling “experts” don’t know a thing about frame geometry, especially as it applies to riders under 5’6″.  One of the (few?) nice things about being an accountant by trade is that math comes naturally to me.  So, understanding the complexity of frame geometry has always been a high priority.

The 650b frame I built back in 2012 is currently being repaired with additional brazing on one of the lug joints that I didn’t do so well at filling with silver the first time out.  When that frame has been sand blasted and painted, I’ll build it up.

Rivendell Appy in shipping garb

Meanwhile, I received shipment of the Rivendell Appaloosa and 650b Velocity wheelset I had ordered earlier this winter.  When the frame arrived I was amazed to see that Rivendell had protected and packaged the frame in a way that only bike geeks can appreciate. As a buyer of bike frames, I have received countless frames shipped with no tubing or drop out protection.  Some eBay sellers simply do not have a clue as to how to properly ship a bike frame, so: Caveat Emptor.

As expected, this bike’s paint scheme is lovely, in fact, extraordinary for this price point.  The fork crown has ornate patterns, with mounting holes on top to accept stays for a front rack.  The Appaloosa head badge is fun and interesting (it’s a Rivendell!), and all the lugs have been filed and well brazed.  For a frameset that costs the consumer a mere $1,300, the value is clearly reflected in these features.  A Rivendell frame is one step away from custom, but inexpensive compared to custom options.

Is this a cargo bike?

Horseshoe seat tube/seat post drilling

Whether you want a kickstand or not – here is the bracket for it

Beefier than any other dropout – and with two threaded eyelets.

Two more eylets on the rear dropouts

3 rack mounts on the seat stays, plus the eyelets on the dropouts.

Silver tubes – butted and cro-mo

One thing to note about Rivendell frames is that they can have a longer wheelbase and longer chainstays than expected.  This Appaloosa has 51 cm chainstays. That means it is in cargo bike territory for its wheelbase.  For this frame (advertised as 51 cm size), I measured the seat tube as 50 cm and the top tube as 55.5 cm.  These measurements differ from the specs shown on Rivendell’s website.  My measurements are center to center.

There are a few condition issues with the frame.  The seat stay cluster was filed very thin, but the upper portion extends outward, and with a little paint loss, is not ideal.  Also the rear canti stud braze-ons are not well executed.  They look unprofessional, but after examination I think they will be safe to ride.  The head badge was not glued evenly to the head tube, as shown above.  Naturally, I am documenting these issues in case anything arises with the performance of the bike.

Because the frame is heavier than other frames that I ride, I expect to replace the FSA headset and the low-end Shimano bottom bracket.  I’ve got lots of interesting vintage options in my parts bin that are lighter weight and probably more likely to last through the ages, as well as provide better performance.  Smaller riders can benefit from weight savings, and I intend to focus on that as I consider options for components.

Meca Dural Duralumin Bicycle Frame Construction

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Meca Dural bottom bracket shell

From the 1930’s through the 1950’s, the French were enamored with aluminum bicycle frames, even though steel was the material of choice for most builders.  A number of examples still exist today, and after disassembling and cleaning this 1940’s/50’s Mercier Meca Dural frame, I can see why.  The bottom bracket shell is a work of art, looking as if it had been machined yesterday, rather than more than 6 decades ago.

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I became curious about the method of joining the aluminum tubes with aluminum lugs, using what I had read were internal steel expanders.  Apparently, at the time there was no method to “glue and screw” the aluminum tubes, a method that was pioneered by ALAN beginning in the early 1970’s.  The only joining methods which were available then were gas welding the tubes – a process used by Nicola Barra; connecting octagonal aluminum tubes into aluminum lugs with connector bolts – a process used by Pierre Caminade; joining the tubes with aluminum lugs and wedged internal expanders – the method used by Meca Dural, and other other hybrid methods involving pinning the lugs, and using a steel rear triangle.

When I passed my magnet over the frame, I picked up no attraction, except for a very faint pull near the lugs.  You will note that the chain stays and seat stays are connected with a combination of bolts and aluminum sleeves, and that the bottom bracket shell is held in place with two large bolts connecting the lug to the chain stays.  The aluminum sleeves do double duty as the brake bridge and chain stay bridge.

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The seat tube/seat stay lug is pinned, as you can see above.  But what about the main tubes – how do the internal expanders work?

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As it turns out, it was fortunate that the Meca Dural headbadge was missing, which allowed me to peer into the head tube lug to examine the expander inside.  My magnet told me that the expander is steel, and the method to accomplish the expansion process seemed to involve a steel tab which was probably manipulated with a special tool.  When you think about it, the same idea is used for quill stems inserted into threaded steerer tubes.  That seems to have worked pretty well, so why should these lugs be any different?

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At first I wasn’t sure of the purpose for the large holes underneath each of the two headbadges.  Upon closer examination, you can see that the head tube and head lugs are actually machined as one piece.  The holes are necessary so that the expanders can be inserted to join the top tube and down tube, necessitating a hole for each tube.  And that is why there are always two headbadges on every Meca Dural frame -to cover these holes.  That’s one mystery solved.

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One thing that seems true of older aluminum frames is their flexibility, relative to steel frames.  My ALAN is a very flexible frame, but not too flexible.  I guess you would say it is flexible in the right kind of way.  To satisfy my curiosity about this frame’s flex characteristics, I squeezed the rear dropouts to test the amount of flex.  Then, in my unscientific experiment I compared the amount of flex on this frame, to all the other bare frames hanging in my shop, all of which are steel, and some of which are Reynolds 531.  I was able to flex the dropouts on the Meca Dural about 7 or 8 mm, using my weaker left hand at full force.  On several mixte frames, I could barely move the drop outs 3 mm, and on a diamond vintage Reynolds 531 frame, I could flex the drop outs about 6 mm at full force.  That’s a significant difference in flex, and it will be interesting to see how this frame rides once I have it restored.

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With just some minor polishing with a wadding cleaner (I use NEVRDULL), the frame shines beautifully.  I need to source some 650b wheels from the period, because at some point someone tried to install 700c wheels on this bike, and that is how the bike was configured when I acquired it.  The spacing at the rear dropouts is 115 mm, so it would be hard to find the vintage hubs to build a wheel set, even though I have a nice vintage set of rims.  Instead, I am on the hunt for a donor vintage bike from the 40’s or 50’s which can give me a decent 650b wheelset, and maybe a few other parts to add to my collection.

 

Goodbye, Little ALAN

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1980's ALAN Cyclocross

I have enjoyed riding around on this tiny ALAN cyclocross bike.  I originally purchased it several years ago for a family member who is about 5′ tall on a good day.  She had been riding a small framed newer Trek with 700c wheels, and while the Trek has nice components, the geometry is pretty awful.  But, many shorter riders have never experienced anything different, because the cycling industry has not met their needs.

Enter the ALAN.  It was designed around 24 ” wheels, with a 48 x 48 cm frame.  When I spotted it on eBay it looked like this:

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Those are 170 mm Dura Ace cranks – on a bike with a 24 cm bottom bracket height.  Needless to say, there is no way that you would pedal through corners on this configuration.  So, I began the process of modifying the bike,  and at first I tried this configuration:

I changed out the crankset for a single 152 mm 52T vintage crank.  Unfortunately, this just did not provide the right gearing for the bike.  So, I reconsidered the whole build.  The deep drop Cinelli bars made no sense for a small rider with short arms.  The downtube shifters were also a bit of a reach.  That made me think that a city-type build might be best for this bike.  So, I came up with this set-up using a double 152 mm 50/39 Sugino crankset.  I replaced the rear Dura Ace derailleur with a Shimano Deore XT long cage, but kept the Dura Ace front derailleur, Dura Ace headset, and Dura Ace bottom bracket.  I used some vintage upright bars with a Shimano 7 speed index system.

ALAN in city mode

And this is how I rode around on this bike for the last 2 years (test riding is very time-consuming).  Finally though, my thoroughly enjoyable test riding has come to an end.  So, I needed to really rethink how the new rider would use this bike, as well as how her small size would effect the choices I made.  Since she is used to a road bike configuration, I decided to replace the city bars and shifters with a narrow SR Randonneur bar, bar end shifters (for an easy reach), and these beautiful Modelo drilled levers, which have very small hoods and a short reach to the levers.

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I kept the rest of the bike pretty much the same – here are some photos of its features:

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Dura Ace calipers

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ALAN logo

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Beautiful engraving on the ALAN head lugs, Dura Ace headset

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Shimano Deore XT rear derailleur

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American Classic 25mm seatpost

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Sugino 50/39 crankset with 152 mm arms

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Dura Ace front derailleur

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Shimano 600 tri-color front and rear hubs on Mavic 24″ Open 4 CD rims

If you haven’t ridden an ALAN before, you are in for a treat.  The frame is very comfortable, and hill climbing is a breeze.  The aluminum tubes are screwed and glued into beautiful stainless steel lugs.  This little bike weighs in at 19 lbs!  I used this bike often for my daily Pdx commutes – what a joy.  The tiny wheels make for quick acceleration.  It has been one of the best city bikes I have ridden.

There were some challenges in setting up the bike.  The very short chainstays mean that it is not possible to select certain gearing configurations – namely the biggest ring on the biggest cog and vice versa.  But that is a normal limitation on many bikes.  Also, while I agree with most of the frame geometry decisions on this bike, I am puzzled by the amount of bottom bracket drop selected.  It would have been easy to build the bike with less drop, and that would make it more feasible to use a longer crankset without worrying about pedal strikes while cornering.

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Here is the bike now, ready for its transport to Central Oregon where I hope it will be well-loved and well-ridden.  The seat post and stem height are still set up for my size, showing how small this bike really is, given that I am 5’4″.  I’ll be test-riding it for a few more weeks to make sure everything is just right, and then it will be time to say good-bye to this wonderful machine.  It is a rare bike, and a great testament to the ALAN company’s frame building skills.  Thank you for building this little bike – it is a treasure.

1980's ALAN Cyclocross