American Custom Bicycles in Steel, Titanium and Ti/carbon mix

Materials Technology

Materials

Materials matter. And how you handle them matters, too. At Seven we start with the best raw materials available to us, and then, through a deep understanding of the underlying metallurgy, we refine them to produce the best bike for the person who will ride it.

To begin with, we reject the idea that one material is best for every rider. At Seven, we take a rider-specific approach to materials. For some we recommend steel, for some titanium, and for some we suggest incorporate carbon fiber into the frame.

Titanium, carbon fiber, and steel all have different characteristics that speak to an array of design priorities. Carbon fiber can be light and stiff. Titanium can be durable and tuneably compliant. Steel can be light and springy. All of these are positive and, in hands of an experienced builder, can form the basis for a great custom bike.

Materials

Titanium

Interestingly, while riders have believed for years that the type of steel a frame is made from is supremely important (we agree), they have simultaneously assumed that titanium is just titanium, that it’s all the same.

Nothing could be further from the truth.

Seven uses only US-milled, Cold Worked – Stress Relieved (CWSR) titanium in our custom frames. We do that because no other titanium available today has a longer fatigue life or higher tensile strength. We know that’s true because we have a fatigue tester here in our shop and regularly submit tubes to rigorous testing. Pushing materials to their breaking point is a great way of finding out how good they are, and our research indicates that the titanium we source is the strongest available and maintains that strength over significantly longer periods than the titanium available from mills in Asia.

We always want to use the best materials, because we want to build the best bikes, but we also have a commitment to lifetime warranties that prevents us from cutting corners with lower quality products. When you buy a custom Seven, you put your faith in us to produce a bike that will fit like a glove, corner on rails and last forever. American CWSR titanium allows us to repay your faith with a frame of uncompromising quality.

Carbon Fiber

Of course, it is also possible to mix materials to take advantage of an even wider range of benefits, as in our Ti/Carbon mix frames.

When we think of the inherent qualities of titanium, we think about compliance, the ability of the material to flex and return to its initial position, strength, durability and customizability. Titanium is light and strong, lasts forever, and can be tuned through astute tube manipulation to produce very specific ride qualities.

Carbon fiber is, in most instances, even lighter than titanium and adds the value of excellent vibration dampening, so that when we mix it with titanium, we get extremely light frames that produce a butter smooth ride.

In order to get to the optimal frame performance, we are strategic about where we use each material. We use titanium at the joints, where strength and compliance are most important, and we use carbon in the main tube sections, where weight can be sacrificed and road vibration can best be dissipated.

Steel

At Seven, we have always built our frames from tubing specific to each rider. We take into account rider size, riding style, preferred road feel and general riding conditions. We may select a top tube or seat tube from one of the big steel tube set makers if it’s appropriate, or we may take raw steel tubing and butt it by hand, here in our factory, to craft the exact ride a customer is looking for. We butt and bend all our steel chain and seat stays in house. When the bike is custom, one size never fits all, and one tube set is never appropriate to every design.

This is the reality of building in steel if you want a custom bike, one tuned for both performance and comfort. There is nothing wrong with the tube sets of legend, but it is true that each set is only a limited solution for a small subset of riders. When building custom bikes, we feel it is important to think more deeply about materials, to see how they can best be applied in any design and to push back against convention, whenever necessary.

Tube Sets

Titanium Tube Sets

Cirrus™ Ultra-butted 3-2.5 titanium

Specifically engineered for light weight, Ultra-butting varies the wall thickness continuously along the tube, shaving weight wherever possible for our lightest tube set ever.

Argen™ double-butted 3-2.5 titanium

The cornerstone of our materials offerings, Argen provides the perfect balance of lightweight, responsiveness, and durability.

Integrity 325™ straight-gauge 3-2.5 titanium

A high-performance straight-gauge tube set for ultra-durability and greater affordability.

Titanium/Carbon Fiber Tube Sets

Cirrus TC™ Ultra-butted™ titanium and carbon fiber

Features a blend of filament-wound carbon fiber and our super-light Cirrus Ultra-butted 3-2.5 titanium.

Argen TC™ double-butted 3-2.5 titanium & carbon fiber

Features a blend of filament-wound carbon fiber with our high-performance Argen™ tubing for lighter weight and excellent dampening characteristics.

Steel Tube Sets

Origin™ double-butted steel

A custom blend of the highest quality steels, making possible the best performing lightweight steel frames available.