Focus: Victoire stainless steel frames
We are also making frame in the most prestigious configuration of steel: the stainless steel. Coming from Reynolds 953 or Columbus XCr range, stainless steel offers the best mechanical features available on the market. For example, in the Reynolds range, the tensile strength of stainless steel is 42% higher than the 853, their most advanced steel, and 100% higher than the 631 (equivalent to the Columbus Zona). Its strength limit is two times higher from titanium. Therefore, a steel frame will keep its mechanical features for a long time. Add the fact that this material does not rust so you can easily leave it with its raw appearance. A stainless steel bike is above all a timeless bike.
This material requires a great attention, from machining to fillet-brazing, which are more complex than a regular steel. That's why it is more expensive than regular steel.
COLUMBUS XCR OR REYNOLDS 953 ?
Here is a little comparison between the two ranges of stainless steel tubing we use :
The Reynolds 953 offers the best mechanical specification. It is the most resistant reference on the market.
- [ + ] : thanks to its high mechanical specs, we can get very thin tubes. For a same sizing, we can use tubing of a smaller diameter and make frames slightly lighter.
- [ - ] : it is hard to work and there is no bended rear triangle, that's why we use it mostly on road bike. Tubing maximum diameter is 36.4mm, so we can not use it for every cyclist morphology.
The Columbus XCR mechanical specs are between the best steel and the Reynolds 953, so it is easier to use.
- [ + ] : it can be bended so we can use wider tires. The down tubes are available from 31.7mm to 42mm, so it can be used for every kind of morphology and riding, from road to gravel. There are also some hydroformed tubing.
- [ - ] : even if it goes better, it can be harder to get. Unlike 953, the XCR range doesn't offer biconical seatstays, that are useful for some projects (small size or light weight cyclist)
As you can see below, in most of the case, the two ranges can fit. The choice is made according to the client's preferences and the availability of the material. We can also mix the XCR and the 953 on a same frame.
What is the influence on our bicycles?
- With the same tubing diameter, the stainless steel enables to make lighter frames. Indeed, the stainless steel is more resistant than standard steel, so we can use thiner tubes for the same resistance.
- At the same weight, a stainless steel frame will be stiffer than a steel one, because we will be able to use larger diameter tubing.
These are some datas about the tubing we use:
• Reynolds 953 (stainless) tensile strength : 1900 Mpa
• Reynolds 853 (top of the range steel) tensile strength : 1150 Mpa
• Reynolds 631 (middle range steel) tensile strength : 850 Mpa
• Columbus XCR (stainless) tensile strength : 1300 Mpa
• Columbus Niobium (Spirit, HSS and Life steel ranges) tensile strength : 1100 Mpa
• Columbus 25CrMo4 (Zona, Max, 29er steel ranges) tensile strength : 800 Mpa
• Aluminium 6061 (the most common on the bicyles) tensile strength : 325 Mpa
So a 953 will be 5,6 times more resistant than a 6061 aluminium : so for the aluminium frames we have to increase a lot the thickness and the diameter to offset this lower resistance. As a result, this oversizing cause a frame too stiff. For informations, Reynolds titanium tubing have a stiffness two times lower than standard steel.