MY "TEN SPEEDS"

 

 

MY "TEN SPEEDS"

 

 

 

 

SITE INDEX   FINDING   BICYCLES   WORK SHOP   TRADING   WHAT'S NEW?

MY "TEN SPEEDS"

 

 

BICYCLE QUALITY - INTRO

WHAT ABOUT YOU?

CHOOSE THE RIGHT BICYCLE

FRAME & FORK QUALITY

WHEN BEST ISN'T BEST

FRAME & FORK  INTEGRITY

DENTED FRAME OR FORK

BENT FRAME OR FORK

MODIFIED FRAME OR FORKI

REPAIRED FRAME OR FORK

ENVIRONMENTAL DAMAGE

FRAME & FORK MATERIALS

FRAME SET DROP-OUTS

CLAMPS & BRAZE-ONS

FRAME CRAFTSMANSHIP

CHARACTER & PERSONALITY

 

FRAME AND FORK DROP-OUTS

Drop-outs, which will frequently be referred to as drops, are the four points on a bicycle, where the wheel hub axles fit into the frame and forks.  There are two rear drops and two front drops.  And, there are two fundamental kinds of drops – Pressed and Forged steel and/or some other metal alloy.  For the purpose of this discussion, the focus will be on steel drop-outs.

Pressed, or frequently called Stamped, drops are made from a flat piece of sheet steel.  The drop is usually die-cut from the sheet and then pressed into its final shape.  The pressed or stamped drop is entry level and/or Old School stuff.  The pressed drop is the easiest and cheapest to make.  And, as one might expect, the least desirable from a collector’s point of view.  They are also very weak when compared to their more sophisticated forged cousins.

Generally, it is very easy to recognize stamped or pressed drops.  Usually, the forged drop will have the rear derailleur hanger included as an integral part of the drop.  In other words, the drop and hanger will be a single piece.  That said, stamped drops can be similarly sophisticated in appearance, also.  Without careful inspection, a high quality stamped drop (if there is such a thing) could easily be mistaken for a forged drop.  I know because I have made this mistake before.  I now look very closely at all forged drops.  They are a very important part on any vintage road bike frame set and should be treated accordingly.

The forged drop is a piece of steel that is shaped through the process of forging.  Forging, simplified, is the process of pouring molten metal, in this case steel, into a mold and allowing the metal to cool.  Once cooled, the forged piece can be, and usually will be, worked further to precise specifications.  This style of drop is very strong when compared to its pressed steel cousin.  Forged drops usually have machined faces that add considerably to the precision of the frame component.  Forged drops can, and often do, have axle positioning screw adjusters such as those on this early eighties Benotto 1600 forged drop-out.

Needless to say, the forged drop is quite a bit more costly to make than its lesser brother, the stamped drop.  In the case of the pressed steel drop, fabrication is a one step process.  The drop is cut from a sheet of steel in a single swipe of a hydraulic press, bent into shape, perhaps at the same time and added to the pile, ready to be installed.  There is no finishing of the piece, finishing being defined as polishing to improve appearance or machining to enhance performance.

Making a forged drop involves several steps, all of which involve human inspection and refinement.  The drops is forged and allowed to cool.  Then it is machined to precise specifications.  After which threads are cut allowing for installation of an axle adjusting screw.  Threads must also be cut in the derailleur hanger.  Finally, the entire piece is polished until it looks good.  This multi step process costs money but the results are worth the extra cost, as far as I am concerned.  When strength, precision and user friendliness are the issues, the forged drop is the way to go.  And, I guess, that appearance must also be included in the forged drop's list of virtues.

Forged drops frequently bear the manufacturer’s name such as Campagnolo, Gipiemme, Suntour, and Shimano, just to name a few.  The name can be either, stamped into a machined surface, or cast into the forging itself, as was the practice with Simplex drops.  Campagnolo commonly stamps the Campagnolo name into the machined face surface that the quick release clamps against.  Many other drop manufacturers follow this example and the information is quite easy to see, when inspecting their drops.  Of course, there are issues to complicate this inspection situation…

Some bicycle manufacturers are having their own name stamped onto forged drops.  Bianchi, Benotto, and a pretty good assortment of others, will lay claim to the forged drop.  As often as not these drops will be made by Campagnolo or Gipiemme or…  You get the idea.  The point is, you cannot be sure who made the drop, unless you investigate.

DROP-OUT SPACING

I rarely run across a vintage road bicycle frame set, that is still straight and in accord with original specifications.  Most are bent, ever so slightly, but bent none-the-less.  I am sure that this comment will sponsor a great deal of concern, but it must be taken with a grain of salt.  I can fix a frame set, that is a wee bit of alignment (bent), and so can the average person.  No special tools are required to do so.  But a straightening a frame set, that has suffered more severe damage, might well prove to be beyond my skill level.

The distance, between the inner faces of the front drop set, will measure 95mm for older forks and 100mm for newer vintages, most of the time.  The rear drops spaces come in a variety of widths, also.  The more cogs on the freewheel, the more space required between drop faces required.  A five speed rear hub and freewheel set will require a rear drop space of 120mm, while a six speed assembly will usually require a full 125mm between the inner faces of the rear drops.

I look to this drop space information as a first indicator of the frame's geometric integrity.  If the rear drop space measurement is bang on, 120mm or 125mm, chances are there is no frame misalignment, at all.  However, if these measurements are not on the money, further investigation is mandatory.

Using the front drop space measurement to help me determine, if a fork set is bent or not, is a bit more complicated.  For me, the quickest test of fork set structural integrity is to look at the front wheel.  With the wheel properly installed in the front drops, consider the rims relationship to each of the fork blades.  Does the wheel rim split the difference evenly?  If so, no worries - usually.  If not, further investigation is mandatory - always!

I tend to focus my interests on older road bicycles.  As bicycle's vintage closes in on present day, the drop spacing continues to increase.   Newer steeds, those with seven, eight, and so on, rear hub/cog assemblies, require greater rear drop spacing.   Modern drop spacing has increased increase to 130mm, the width needed to accommodate the wider hubs of today.  If the rear drop spacing on the bicycle is 130mm or greater, you will be dealing with a fairly new vintage bicycle.  Or one that somebody else has modified.  It is hard to tell the difference sometimes.

Understand the drop spacing issue is important.  Not so much so, when choosing a bicycle to restore and ride.  Drop space will count for little at that point in the build.  However, when it comes time to order or build up a wheel set, it would be nice to ensure that the wheel set fits the frame set.

DROP-OUTS - HORIZONTAL OR VERTICAL

There are two distinct styles of rear drops.  Three actually, when one considers the Track Bicycle.  For the purpose of this discussion, the focus will be on the horizontal drop as compared to the vertical drop.

The horizontal drop is really not horizontal at all – but it is close to it.  Gently sloping towards the front of the bicycle, the horizontal drop allows for adjustment of the front/rear positioning of the rear wheel.  The  longer the horizontal run, the more adjustment available.  Axle fore aft adjustment is required to help take out chain slack on bicycles not fitted with a rear derailleur.  The spring loaded derailleur will deal with chain slack on a "Ten Speed".  Only wheel position adjustment will take chain slack into consideration, when a Single Speed or Fixed Gear bicycle is concerned.

These horizontal drops, the forged ones only, often have wheel aligning screws built into the assembly.  The purpose of these adjusters is to allow for precise placement of the axle ends, to ensure that the rear wheel is in line with the center-line of the bicycle.  The vertical drop does not need the adjusting mechanism.  The rear wheel axle slides up, almost vertically, into the drop.  The rear wheel is automatically set in a position, that assures alignment with the bicycle’s center-line.  Needless to say, there is no opportunity for front to back adjustment, hence the vertical drop should not be considered for anything other than a rear derailleur equipped application.

REAR DROPS AND DERAILLEUR HANGERS

Unless the bicycle is a Single Speed or sports an internally geared rear hub, there will be a need for a means to attach the rear derailleur.  Almost all forged drops include a derailleur hanger as an integral part of the drop.  In other words, the drop and the derailleur are one piece.

Some forged drops and most stamped drops do not incorporate a rear derailleur hanger into their structure.  More often than not, an entry level bicycle will use a separate derailleur hanger bracket to secure the rear derailleur.  Is this better or worse?  It depends, and time and experience will teach you about what it depends on.  There are no rules with this issue.  For now, be content knowing that the separate hanger is weaker but easier to repair, if it does get bent.

FRONT DROPS AND LAWYER LIPS

Thought that I would mention "Lawyer Lips" because I think that the term is funny.  Front drops are sometimes built with ridges, designed to prevent the front wheel from falling out if the quick release is secured too loosely.  These circular ridges are there for safety reasons driven by legal concerns - hence the term "Lawyer Lips".  And this safety feature is not all that bad of an idea for street use.  However "Lawyer Lips" have no place in the racing arena.  Racing is about going fast and getting there first.  "Lawyer’s Lips" dramatically slow down the removal/installation of the front wheel.

The concept of "Lawyer’s Lips", though a new term, is not a new idea.  Older bicycles with pressed steel front drops, frequently had special washers on the front wheel axles that were designed to lock the wheel to the front drops.  Again, the purpose was to insure that the front wheel would not fall out if the hex fasteners were secured too loosely.  The result, of course is added safety for the street and lost races on the circuit.

There is little else that one needs to know about drops-outs when inspecting a bicycle.  Forged are the best from all points of view, be they cosmetic or mechanical.  However, do not discount acquiring a bicycle just because it does not have forged drops.  They are only one of the many things that help to define a quality frame set.

NEXT - FRAME CLAMPS AND BRAZE-ONS

 

 

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