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2002 bikeNOW P/L
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bikeNOW P/L
Step 3
Choosing a frame requires some consideration and our staff can help you with technical information. Aspects to consider include, the size to suit you, how the bike handles, resistance to corrosion, weight, colour, shock absorption and suspension, resale value etc. Market trend is toward aluminium for price, frame repairs, resale value and weight. However excluding Hi Tensile steel, there are pro’s and cons to all choices. We also only deal with companies big enough and proud enough to treat you like gold in the event on a problem. There are so many companies that do it cheaper at what cost? Some brands mislead consumers into thinking their product is better than it actually is with colourful marketing and different frame designs. This is clear with some of the cheap rigid MTB frames that look funky like a dual suspension bike, they are only made that way to look like you have an awesome bike whereas they may just be buying a heavy clunker that you wouldn't trust off a step or two.
Without a doubt the most important aspect to buying a bike is how the bike feels to ride. We can alter your ride position do a degree during fitting but it helps to work with a brand that has made the bike to suit you. For example for a rider that commutes and perhaps does a bit of cross country riding in the hills we would recommend a lighter more agile bike compared to a lunatic who wants to jump off grandma's roof. To get into the zone, our staff can help you with information regarding how each bike feels and arrange a test ride so you can feel what we mean.
Although we cannot cover the intangible we can however document the material differences;.
Heat Treating is a thermal process that raises temper or hardens alloys, (steel as well as aluminium). T6 (oven) or T4 (bath) can increase strength by up to 30% and allow tubing to be thinner and maintain equal strength
Butting: Double or triple Butting refers to the wall thickness of a frame's tube being sleeved or tapered thicker near the join while keeping the majority of the frame tube lightweight. Lightweight tubing on its own reduces the weight, however, butted tubing uses less metal and allows the majority of the frame to be considerably lighter without compromising frame strength.
Most bicycle frames are made from one of three materials:
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| Steel | Aluminium | Carbon Fibre |
Why choose one over another? Many say that steel gives a very comfortable ride and Alloy is too harsh and some say the opposite however having tried many of each over the last 27 years I personally conclude that it depends on the individual frame. There are some alloy frames that are rigid and some steel that flex.
What we want is a frame that flexes to absorb shock and vibration while maintaining lateral and drive stiffness as well as good geometry for handling, lightweight, corrosion resistant, looks good and hold its value. The manufacturer has expertise in creating a frame that will flex in one way but not another by using different tube kits and build processes.
Steel Frames can be made of two different types of steel,
Hi-Tensile (“HT”) steel has a very high carbon content making a soft (weaker), heavy frame that is not ideal but is less expensive. Bicycle manufactures often mix HT steel and Chrome Molybdenum (Cro- Mo). The frame label; Part, Main and Full Cro-Mo is very specific. (see icons). If a sticker reads Cro-Mo but nothing else, it will refer to that tube only and the only Cro-Mo used is in that one tube. It may also be a thick, heavy plain gauge tube (not butted), and may be no better than HT.
Cro-Mo is made from Carbon, Iron, Chromium and Molybdenum. Cro-Mo is lighter and much stronger. Extra strength allows thinner walls and / or butted tubes to further reduce weight.
Cheaper steel frames are the worst of all choices however the top end ($1500 plus frame only) can be awesome. Still a bit heavier but very good drive properties and comfortable. Generally steel frames are heavier and softer and will rust if exposed to the weather.
With Cro-Mo frames there are many different manufactures making many different tube kits. A Cro-Mo sticker on the frame may suggest the frame is better however it may be a low quality, thick wall tube that is rolled from a sheet of steel and welded. The better quality Cro-Mo tubing is available in;
- Seamless that has no join.
- Cold drawn which is a higher quality manufacturing process to result an even stronger tube.
- Double or triple butting explained above
You can rely on known manufacturers with steel and they will have the label of what tubing kit is used. Two reliable providers are Reynolds and Columbus.
Aluminium Frames are made from one of two different grades of Alloy.
7000 is a material that is preferred by most manufacture's because it does not require heat-treating therefore it is cheaper to manufacture.
6000 must be heat-treated after welding and has a higher resistance to stress hardening. Most 6000 series tubes are 6061 however Alcoa and Giant have produced 6013 (CU92) that has an even higher tolerance to stress hardening.
Aluminium is about 35% as dense as steel, therefore to maintain stiffness manufactures use larger diameter tube sets. With Aluminium frames there are many different manufacture's making all different tube kits. Some frames may be a low quality, thick wall tube that heavier and softer. The better Aluminium frames are much lighter and far more brittle. One of the benefits of aluminium is that the will not rust.
Alloy generally creates a lighter frame with reasonable vibration absorption. If you are after absolute performance, you will have to look at the better frames like Giant TCR (not OCR) to avoid a sluggish feel under drive. The brittle frames like Giant TCR are nothing short of fantastic and the difference is very noticeable in drive and weight however they tend to have a harsh ride therefore you may notice the better frames often have Carbon fork, seat post, head stem or rear stays of the frame to soften the ride.
Carbon Fibre frames are either carbon fibre tubes glued to aluminium lugs (joins) that are a little heavier and not as stiff as Monocoque (one piece). Monocoque is where the entire frame is made in one piece. Monocoque is the most rigid of all lightweight frames and offers a particularly comfortable ride, no corrosion, looks good and has a high resale but is more expensive. Trek OCLV frames are the leaders in Carbon.
Handling - Geometry How the bike feels to ride is a very important consideration. There are many factors that effect how the bike feels to ride. We can alter some variables to get the right feel like changing seat position and different handle bars or stem position however, the most important is the actual geometry of the frame which can not be a altered. Our staff will help you factor the differences between models based on your intended use.
Size to suit Some frames, although might be the right size, might be too long or short in the top tube to achieve your preferred reach. We need to make sure we fit the bike to your body length as well as your seat height. More info on sizing? Click here
Weight A heavy frame is above 2kg. Some steel road frames weigh around 2.2kg, aluminium from 1.1 to 1.75kg and carbon is 1.02kg to 1.5kg. Anything below 1.5kg is well into the high performance area as long as the frame's rigidity has not been compromised, as flex will absorb power.
Suspension Frames: Information on suspension frames coming in step 5.
Don't get caught placing too much emphasis on the frame material unless your into top performance or your concerned about corrosion. Most bike frames function well for recreational use. (excludes department store bikes made from pluming pipe)
Step 4
