Frame Materials and What to Buy |
02-Jun-2016 |
Looking for a new road or mountain bike and discovered a whole range of different frame materials? I've put together a brief run down on some of the characteristics and benefits of each material to help simplify your decision.
STEEL
"Steel is real"1 as the old saying goes, or is it a new saying coined when alternative frame materials became more and more popular? Steel was the material of choice for a long time in the bike industry until aluminium came along in the 1970 and 80's.
Steel is durable, totally resistant to fatigue stress (when used for standard bike riding anyway) and easily repaired. Its malleability allows dents to be hammered out and a broken frame can easily be welded together again.
These qualities, along with its enormous strength and elasticity, make steel a popular choice for cargo loaded touring and trekking bikes.
The elasticity also produces some flex under load which some say results in a "springy" feeling while riding. I owned and rode a steel frame for many years and while I loved it, I also found it hard to honestly quantify the difference in the ride compared to a good alloy bike...maybe it's just me.
While steel is often viewed as the heaviest frame material, high-end chromoly can be as light as aluminium, but stronger and arguably more compliant or comfortable to ride.
Like all frame materials, not all steel is created equal:
Titanium also has many of the qualities of steel, but is lighter and more expensive again. It is perhaps more durable, but also much more difficult to work with if repairs are needed (unlikely!).
Why Would I Buy?
So if you are after a touring bike to load up with panniers, many brands offer a steel bike for this exact purpose. Alternatively, if you want something custom or a bit different, with specific ride qualities that you can hand down to your grandchildren, perhaps titanium and chromoly is for you.
ALLOY
6061 aluminium is predominately an alloy of aluminium and magnesium and is the most popular form of alloy used in bicycle frames.
7005 is an alloy of mainly aluminium and zinc. Untreated 7005 can be found in cheaper mass market alloy bikes while the heat treated version, which results in a very strong and light alloy, is used in higher end models.
Why Would I Buy?
Aluminium bikes have made high level technology and performance available to everybody, so if you're on a tighter budget don't worry, alloy bikes will do everything that is required and more.
Butting
Single butted tubes are thicker at one end, like the seat tube which is thicker at the bottom bracket junction.
Double butted is thinner in the middle than either end where the tube is joined or welded.
Triple butted takes the next step with three variations in tube wall thickness.
CARBON FIBER