The decals/labeling on this particular offering do not identify this frame and fork set as a Bertin model. We have been told this is not all that uncommon in Europe, because frame builders will manufacture frame and fork sets for local shops and allow them to choose their own color scheme and decals. We presume this is the case to help local shops in Europe differentiate their frame and fork offerings from competing shops (at least the cosmetic appearance of such frame and fork offerings). One other note in this regard...
We have noted there does not appear to be a clear coat over these decals, so they may peel off (with a little effort) in the event someone prefers a cleaner look (without any decals). This offering is for what we believe is a new-old-stock Bertin (made in France) road frame and fork with a metallic red enamel finish that is in nice condition.We believe it's a mid to late 90's model with butted steel tubing (although we are not sure what brand/model tubing) and a curved-bladed steel fork having a 1 threaded steerer tube (that is uncut, as there is a threaded section extending above the head tube that measures at least 50 mm). The frame tubes are TIG (Tungsten Inert Gas) welded and both the top tube and down tube appear slightly oversized, while also retaining a somewhat aero shape i. We were not provided any information with these frames, but please still review the detailed notes that follow, as we have taken some measurements to help assess fit and function. Please also understand that while the measurements below are not factory specifications, we have tried to be as accurate as possible using the various measurement tools available to us i.
Calipers, protractors, rulers, tape measures, scales, etc. Some of these measured specifications include the following (and please note all length measurements are center-to-center).Frame size (seat tube length): 58 cm. Weight (frame and forks): 6 lbs 9 oz (frame weight is 4 lbs 10 oz and fork weight is 1 lbs 15 oz). Rear dropout spacing: 130 mm. Top tube length: 58 cm. Head tube angle: 74 degrees.
Seat tube angle: 74 degrees. Chain stay length: 41 cm. Head tube length: 20 cm. Head tube inside diameter (for headset): 30.2 mm. Seat tube inside diameter (for seatpost): 27.2 mm (measured by inserting a seatpost sizing rod and noting the first visible marker above the seat tube).Seat tube outside diameter (for clamp-on front derailleur): 28.6 mm. Bottom bracket shell: 1.37 x 68 mm (English threaded). Braze-ons: Dual control brake/shifter lever cable stops on the down tube (for cable routing when dual-control levers are used), brake cable housing stops on the top tube, shifter cable housing stop on the right chain stay, water bottle cage mounts on the down tube and the seat tube and chain peg on the right seat stay. Other notes: Semi-vertical rear dropouts with built-in derailleur hanger, recessed brake caliper mounting holes and a stamped/pre-drilled hole on the underside of the bottom bracket shell for cable guide block (not included, but inexpensive part to obtain). We understand there are other frame/fork measurements or characteristics that impact ride qualities and performance, but the above specifications should provide for a good starting point. We also ask that you scan our notes that follow, as we have attempted to provide some general commentary that supplements/supports the above information. Please understand we are only trying to make some very basic observations. We understand our comments may not hold true under all circumstances and that we barely touch on a couple of topics... But we still hope our notes provide some assistance when considering this offering. We believe most would agree that head tube and seat tube angles have a fairly significant impact on ride qualities... With the emphasis on the head tube angle. These angles may range anywhere from 68 degrees to 75 degrees. The shallower the angle, the more stable and comfortable the ride should be at lower speeds, while steeper angles promote a more responsive/rigid feel that generally handles better at higher speeds (but is usually less comfortable). Not as comfortable as a frame with shallower angle measurements. The wheelbase measurement also appears to impact ride qualities. In an attempt to provide some basic guidelines, wheelbase measurements generally range from around 100 cm (or less) to nearly 110 cm... With ride qualities described above dependent on where a measurement is positioned on this continuum.
The chain stay measurement is a component of the wheelbase, so it's not surprising to note a consistency between the two measurements. In other words, a shorter chainstay measurement will shorten the wheelbase and generally translates into more responsive/performance oriented ride characteristics with better acceleration and climbing qualities. A longer chain stay measurement, similar to a longer wheelbase measurement, will usually improve overall ride comfort, while conceding some of the high-speed responsiveness achieved with shorter dimensions. Lastly, in an attempt to provide some additional guidelines, chain stay measurements generally range from around 40 cm to 45 cm (or possibly longer) with ride qualities described above dependent on where a measurement is positioned on this continuum. Fork rake, like the chain stay measurement, is a component of the wheelbase...
But to a lesser degree. A longer fork rake, as in the case of a steel touring fork with exaggerated curves, will generally provide fairly significant road dampening qualities.
From our own personal experience, we always noted the way a touring-style fork will literally bounce up and down around the dropouts, absorbing the bumps in the road, but this feeling never made it up through the steerer (or at least to the degree noted at the dropouts). We realize there are other factors at work here, but we still wanted to provide one example of the impact fork rake may have on ride comfort. Another thought regarding fork rake is it's impact on the "trail" of a bicycle. Generally speaking, the longer the "trail" the greater the inherent tendency the bicycle will track in a straight line. A shallower head tube angle and a shorter fork rake are probably the most significant contributors to a longer (and preferred) "trail" measurement.
Our general assumption here is that frame manufactures have long since incorporated the preferred "trail" measurements in their frame and fork designs, so the fork rake and head tube angle should compliment one another in this regard. Please note the dimensions wheelbase, chain stay, etc. On this particular offering are fairly short, so consistent with the angle measurement discussion above, this frame should be fairly responsive and perform fairly well at higher speeds, but it probably will not be as comfortable (relative to a frame with longer dimensions). We are not going to do this topic justice, but will still try to provide a few general/basic observations. Most vintage frames were made with steel tubes and although there were different brands/types...
This was the preferred material for many years. Steel is generally the heaviest of the material choices, but some still prefer the ride qualities of a steel frame. Generally speaking, steel frames may retain several desirable high-speed ride qualities... While the inherent dampening qualities of steel help to alleviate some of the rigid/uncomfortable ride characteristics that usually accompany high-speed performance. Maybe the most significant historical advancement made with respect to steel frames was the idea of butting the tubes.The motivation behind this concept was to maintain structural integrity of a frame by reinforcing the tubes with thicker material at stress points i. The joints of a frame, while reducing overall frame weight by thinning the tubing walls at lower stress areas i. The tubing sections away from the joints. Butted steel frames are still going to be heavier (in most cases) relative to frames made with other materials aluminum, titanium, carbon fiber, etc. , but weight differences are generally not as significant when butted tubes are used.
Like just about anything however, too much of something is not always a good idea. In the case of butted tubes, we've noted some examples (especially in larger frames) where the tubes become so thin in lower stress areas that a frame will literally begin to "wobble" at higher speeds (and this can be especially unnerving on descents). Please understand, we still much prefer a well designed/manufactured butted frame over a straight gauge frame, because the ride qualities are not compromised and a lower overall frame weight is still attainable.Aluminum frames were probably next to achieve some level of commercial appeal... And while it's a lighter material, aluminum frames are generally stiffer and provide a harsher ride (relative to a similarly constructed steel frame). Having said this, aluminum frames generally retain many of the high-speed ride qualities and superior climbing qualities (due to their light weight) desired by more competitive cyclists.
Some would also note that aluminum frames are generally a good candidate for lighter riders, while heavier/stronger riders that generate a lot of torque may want to look at other material options. Another design feature that gained popularity, while the aluminum frames were being introduced, concerned the idea of oversized tubes. The underlying motivation here was similar to that of butted tubing noted above...
Maintain structural integrity and desirable frame characteristics, while further decreasing the overall frame weight. This was accomplished by increasing the size (diameter) of the frame tubing while also thinning the tubing walls. As most will attest, this concept can be taken to the extreme (similar to the butted discussion above), which may also result in undesirable frame qualities. Although, well designed and oversized frame tubes in just about any material are still widely accepted and available on many current frame offerings, which lends support to the merits of this underlying concept. While frames made with these materials are generally more expensive, there are many that believe their basic properties (in addition to their light weight) help to achieve the most desirable combination of ride qualities i.
High-speed performance/responsiveness, while still maintaining comfort and low-speed stability. We believe there is merit to this claim, especially when considering the resources frame manufacturers are dedicating to research and development. Having said all of this, please note this particular offering is a steel frame with butted tubes, so some of the inherent road dampening characteristics (of steel) noted above, may translate into a slightly more comfortable ride, even though this frame also has relatively steep angles and short dimensions. All of these Bertin frames and forks are new and unused... And came to us bulk packed with some cardboard dividers and packaging to help preserve their cosmetic condition.
Still, the condition of these metallic red frames is not perfect, so please expect some blemishes (scratches and scuffs) on each offering. We will do our best to point out significant cosmetic flaws, so there are no real surprises, but please keep in mind there are going to be some shopwear-type marks on each of these offerings. Having said this, as we inspect this particular frame and fork, we see little in the way of shopwear-type marks. We see some minor blemishes on the fork and a few on the frame, but overall it's one of the nicer Bertin frame and fork sets we have uncrated to-date.Probably the most visible of the blemishes is a scratch/scuff clearly visible on one of the fork blades in the 8th picture of the sequence to the left. You may visit our store by clicking on this "Store Home Page". Link and please note the product categories on the left side of our "Store Home Page". We have also moved our "Terms and Conditions". You may navigate to this page by clicking on the link on the left side of our "Store Home Page". The item "New-Old-Stock Bertin Frame and Fork (58 cm) withButted Steel Tubes. Red Finish" is in sale since Monday, March 7, 2016. This item is in the category "Sporting Goods\Cycling\Bicycle Frames". The seller is "bicyclists_retreat" and is located in Argonia, Kansas. This item can be shipped worldwide.