Custom built frames
Thank you for your interest in Bob Jackson frames. We hope the following information will help you in your decision on purchasing a bicycle frame. The intent of this these pages is to present you with as much accurate information as possible.
Bob Jackson and Bob Jackson Cycles have been building high quality, lightweight bicycle frames for over 68 years. 1995 saw the 60th anniversary of both Bob Jackson Cycles and the introduction of legendary 531 tubing, by Reynolds Tubing. Jackson and his master frame builder Danny Foster were the first to hold a contractors license from Reynolds Tubing allowing them to build with their revolutionary 753 tubeset. The first 853 frames displayed at the 1995 Anaheim International Bike Show were built by Jackson for the Reynolds display. All Bob Jackson frames and forks are fabricated in their own shop in Leeds, England. No operation involving their building and / or painting is contracted out. 1997 saw Jackson Cycles move to a larger and more modern shop, better enabling them to carry on their tradition of hand building quality cycle frames.
Each Bob Jackson frame is individually hand built to the cyclist exact specifications. These frames are fully custom built in the truest sense of the word. When a cyclist is willing to invest in a high quality bicycle, there is no reason why he or she should have to settle for a frame that “almost fits perfectly”. This includes the basic geometry as well as the length of the top tube, a problem of particular concern to woman riders who have difficulty adapting to the top tube lengths dictated by an ”average” man’s body proportions. There are 20 different models currently available from Bob Jackson Cycles. Each model is designed and constructed for a specific purpose. If a manufacturer claims too many purposes for a particular frame, they most likely do not build frames suited for specific tasks. Jackson frames fall into specific categories, Racing, Touring, Club Riding, Track etc. All Jackson frames are built using steel tubing and lug construction, with the exception of a few time trial frames which must be fillet brazed, a discussion of which will follow under “Materials” and “Fabrication Methods”. All frames are finished with a 2 color oven baked finish, “Stove Enameling”, at no additional cost. This includes any of over 90 colors. In addition lug pin stripping is included at no additional charge. To further add to your options, chrome plating is also offered in varying degrees to best suit the individual’s needs or desires. All this combines to create the frame you want, not the frame someone else thinks you should have.
mentioned above, all Jackson frames are built using Reynolds or Columbus steel tubes.
Reynolds TI is the oldest manufacturer of tubes specifically designed for
bicycle frame building. Reynolds currently offers 5 different qualities of
tubing, 525, 631, 725, 753, and 853. Of these 5
varieties many different configurations can be realized. Bob Jackson Cycles
builds main frame tubes with the top 4 qualities only. In addition Jackson
will build using various grades of Columbus tubing.
In addition Jackson will build using various grades of Columbus tubing.
The tubes used in Jackson frames and a brief description of these follows, but first a brief description of “Chromoly” that is so often used to describe bicycle frame tubes. Chrome moly which in its generic state should carry a SAE/AISI number 4130 will in the best case scenario have a tensile strength of 80,000 psi., before welding. These values are for 4130 produced by a reputable steel manufacturer. Generic “Chromoly” supplied by an unnamed source or imported oriental steel should be looked upon with a great bit of skepticism.
Hi tensile steel should best be reserved for plumbing pipes and should not even be considered for a bicycle frame. Jackson will not build with either of these materials.
Reynolds 525 non heat treated chrome moly has been in Reynolds inventory of bicycle tubes for many years. Since 1998 it has been reconfigured and up graded to a strength level very similar to that of Reynolds legendary 531 tubing. The primary reason for it existence is its ability to be tig welded, thus producing lower cost and lower quality frames. It has no advantage over 531 except for this singular feature. Jackson does not use this tubing for the 3 main tubes as there is no added benefit to the cyclist.
No longer produced by Reynolds, due to its inability to be tig welded.
REYNOLDS 631 / 631OS info
Reynolds 631 Air Hardened tubing is a tubeset based on their 853 Air Hardened technology. This tubeset has replaced 531 as the basic material used to construct Jackson frames. The primary difference between 853 and 631 is the lack of heat treating applied to the an 853 tubeset, thus producing 631 tubing. At the present time 631 will only be available as main tubes and must be combined with either 525 or 725 stays to complete the frame. Jackson will be using 725 oval stays with these main tubes in their oversized configurations. This designation will be replacing Reynolds 653 & 731OS tubes. Tig welding is possible, however to bring 631 to its optimal strength level, brazing and the much larger heated area produced will greatly increase the finished joints ultimate strength.
No longer produced by Reynolds, due to its inability to be tig welded.
REYNOLDS 725 / 725 OS info
Reynolds 725 Chrome moly tubing can be used to build a complete frame or can be used as seat and chainstays to produce either 631 or 853 frames. The 725 is an up grade over 525 when used as a stay material. It offers increased strength without an increase in weight.
REYNOLDS 753 / 753 OS
No longer produced by Reynolds, due to its inability to be tig welded.
This was the benchmark by which all high performance bicycle frames have been judged for the last 20 years. Possessing a 195,000 psi tensile is among the strongest tubes currently available for the manufacture of high performance, light weight, ultra responsive road frames. This tubing uniquely combines terrific power transmission ability, lively ride, responsiveness and a high degree of comfort, while producing some of the lightest frames available.
BICYCLE GUIDE tested a sub 20 pound Bob Jackson 753 in their June 1995 issue and used such terms as "The four pound Jackson floated up longish canyon climbs", and "your back just doesn't get sore on this bike".
Unfortunately 753 frames will never be seen in great numbers. Frame builders having access to this material is closely controlled. Builders must be certified as to their proficiency in low temperature silver brazing 753 by Reynolds. Only after having passed a structural test on their work will they be certified and sold these tubesets. Another drawback is the cost of silver brazing material as compared to that of brass, approximately $150.00 per pound compared to $9.00. Having to keep the area to be joined at a maximum of 1200 degrees, tig welders are immediately ruled out, along with their ability to mass produce 753 frames. It is primarily for these reasons that 753 frames are not offered by the bicycle giants. Highly skilled labor and time consuming hand work are not the direction large companies wish to move in.
753 OS This is an oversize version of 753 featuring even better power transmission abilities than normal sized 753. A special 753 Anniversary tubeset has been created for Bob Jackson Cycles to commemorate the sixtieth anniversary of Bob Jackson Cycles and the introduction of 531 tubing. It features specially drawn short butts, reduced wall thickness, oversize seat stays and oval chainstays. Only 60 of these set have been manufactured by Reynolds, once they are gone no more will be produced. Unfortunately all of these have been used.
REYNOLDS 853 / 853OS info
Reynolds 853 is a high strength, 210,00 psi, heat treated, air hardened steel alloy. Careful control of the alloying elements combine to give these tubes enhanced mechanical properties surpassing other materials currently available.
The main advantage of Reynolds 853 is its ability to air harden after joining, a characteristic not shown by other chrome molybdenum / manganese molybdenum materials presently on the market. When building frames using either TIG welding or high temperature brazing, above 1600 degrees, the joints increase in strength as the frame cools to room temperature.
LUG CONSTRUCTION IS THE PREFERRED METHOD OF JOINING 853. It allows a much larger area to be heated than tig welding which concentrates the heat to a very small area at the weld. This completely goes against the “AIR HARDENING” building philosophy of the material and adds nothing to the strength of the joint. It is however a much cheaper joining method, requiring less time and skill to perform.
Due to the superior mechanical properties of 853 tubing, there are several benefits which will translate directly to the cyclist. The wall thickness of 853 has been reduced to 0.4 mm, a full 0.1 mm thinner than Reynolds other top of the line 753 tubing. This translates into a frame weight of under 3 pounds 5 ounces for a 56 cm frame (less fork). Because of the added hardness of this alloy the chances of denting the tubing are no greater than that of present materials being employed. The final significant advantage is the increased stiffness of the frame and its ability to transmit all of the cyclist power into forward motion. The oversized 853 tube set, with its oval chainstays represents the ultimate in power transmission. Aside from the 853 OS tubeset, conventional diameter sets are available which will allow for a more comfortable ride, while still retaining most of the benefits associated with 853 oversize.
853 is currently produced in 8 tube tubesets. There are no fork blades drawn from this alloy. Bob Jackson will supply 853 frames with your choice of fork material., and configuration.
Jackson will build to order any of its frames using virtually any Columbus tubing. Columbus has pushed the envelope of tubing thickness to .38mm on some of their tubesets, approaching the weight of Aluminum. info
With the exception of a few special models, all Bob Jackson framesets feature lug construction. In this day of tig welding there is still something beautiful and functional about an expertly built and finished lug frame. Despite claims of lighter weight (more on this later), the main reason for manufacturers championing tig construction are the cost savings to themselves and the ability to use less skilled labor in their frames construction. Also see enclosed sheet on 853 properties and lug construction vs. tig welding.
Weight saving claims for tig welding must be examined a bit more deeply than that which appears on the surface. Granted the tig fabricated saves the weight if the 2 head lugs, a bit of weight from the set lug, (not the entire weight of the lug) as there must still be some sort of clamp for the seat post height adjustment and finally the weight of the ports (the cast in round or oval protrusions into which the tubes are fitted) on the bottom bracket shell. Now to put some of this saved weight back into the frame, in order to produce an acceptably strong weld and to help prevent burning through the tubes, the tig fabricator will have to specify a thicker butt (tube wall thickness) when he orders tubesets. Thus the weight saved by omitting the lugs has now gone back into the frame in the form of heavier tubes. The only real saving has been in the builder’s expenses, and this has gone directly into his pocket, not into your frame. All Jackson framesets clearly show the type of alloy used in their fabrication, unlike some frame builders who use a generic label, designed to look similar to an authentic decal, but in reality tell the cyclist nothing about the origin of the materials being used.
These frames are designed for serious cycling and as such come in many different configurations to best suit an individual rider’s needs and wishes.
631 / 525 FRAMES (available in 2 different models)
MESSINA, built with Messina lugs, these are conventional long point lugs, frame is built with a uni crown fork & cast bottom bracket shell.
3 WINDOW, These Prugnaut lugs feature ornate cut outs on the head lugs and seat lug and are therefore refereed to as 3 Window lugs, These frames are built with a cast bottom bracket and Cinelli crown. These lugs are a no cost option on 531 Messina frames, and are the standard lug used on the Grand Prix, Vigorelli 531 track frame & all touring frames.
631 / 725 FRAMES (available in 3 different models)
3 WINDOW, built with 3 Window lugs described above, cast bottom bracket shell & Cinelli style crown.
SUPREME / LUGANO, built with cast long point lugs, cast bottom bracket shell and Cinelli style crown.
ARROWHEAD, built with more ornate fully cast Arrowhead lug set, again with Cinelli style crown.
725 FRAMES (available in 4 different models)
NERVEX PRO, these are the legendary lugs used on the finest frames built some 20 to 25 years ago. Frames will be built with these lugs until the supply is gone. Frame includes a very rare Nervex bottom bracket shell and comes standard with a Cinelli style crown.
853 FRAMES (available in 5 different models)
OVERSIZE ROAD FRAMES
SUPREME / LUGANO lugs in an oversize version are standard on all oversize road frames.
ARROWHEAD oversize lugs are available on any 631, 725 or 853 oversize frame.
MUSCLE CARBON FIBRE filet brazed Reynolds or Columbus tubing bonded to a carbon fiber rear triangle.
VIGORELLI track frames are built with either 3 Window or Supreme / Lugano lugs, your choice. Other lug sets are available. Standard crown is a flat cut out crown with no provisions for brakes.
Can either be built with3 WINDOW, SUPREME / LUGANO lugs or fillet brazed. The PROMETHUS time trial frame must be fillet brazed. Any combination of wheel size is available with these frames.
LEGEND, SUPER LEGEND both of these frames are built with hand cut lugs fabricated in Bob Jackson’s shop. Additional ornate work can be done on these frames (Price on application). Standard tube set is 631 / 525, however any other tubeset can be used for the main triangle. The rear end must be constructed of 531 if the Curley rear is to be retained, otherwise the rear triangle can be constructed of any material. Oversize tubes are not an option with these frames.
TOURIST TANDEM, RACING TANDEM are built with either 3 WINDOW or SUPREME / LUGANO lugs. The LEGEND (Curley) Tandem uses hand cut lugs as the Legend / Super Legend frames. Frames are available in either 531 or 631 in standard size or oversize versions.
The spec. sheet shows the seat and headtube angles, top tube length and other standard dimensions of a Jackson. Being a truly custom framebuilder, any of theses specifications can be altered. If you are purchasing a high quality frameset, we at World Class Cycles, believe you are entitled to these choices. Please do not confuse a true custom framebuilder, such as Bob Jackson, with a mass producer claiming to be custom, but offering you none of these choices. As with color choice, there is no additional charge for this service. Our order form and coloring sheet are both designed to help you order exactly the frame you feel you need, not the frame someone else feel you should be riding.
Any Jackson frame can be built utilizing 650 (26”)
wheels. This change allows for the restoration of correct geometry, usually
compromised in smaller frame sizes, and enables us to further shorten the top
tube length, a definite plus for woman riders who usually have to settle for a
frame designed for a male rider’s body proportions. Due to the toe clip
overlap issue, a frame utilizing
700C rims is hard pressed to get a top tube under 52 cm, even at this size the
geometry is seriously compromised.
For more information on
these frames please contact us. There is NO additional charge for frames built
this way. Also available are
custom built mixte frames which allow for a very
low step over height.
Also available are custom built mixte frames which allow for a very low step over height.
If you compare all the choices and options, pound for pound and dollar for dollar, there is no other frame on the market that offers you as much latitude in design freedom and quality as a Bob Jackson. Standard features on a Jackson are either not available on other frames or are additional cost options. The following page outlines the standard features and options available to you. Please feel free to call if there is any additional information you require, you do not have to settle