Frame Materials for the Touring Cyclist. Did you know that: Aluminum frames have a harsh ride? Titanium frames are soft and whippy? Steel frames go soft with age, but they have a nicer ride quality? England's Queen Elizabeth is a kingpin of the international drug trade? All of the above statements are equally false. It is important to understand the difference, if you want to understand differences in frame materials. When you remove the weight, the bar snaps back to its original shape. Different materials will flex different amounts for the same amount of force applied. This is stiffness. Now imagine hanging a heavier weight on the bar, so heavy that it becomes permanently deformed. When you remove this weight, the bar does not snap back all the way to its original shape, but remains bent to some extent. Tips for trimming a motorcycle windshield. The motorcycle frame and body are what hold your Norton Commando motorcycle together. Then isn’t it important to keep them in the best shape possible to. Dirty Acres American Tactical BTR Grille Insert Wrangler 1997-2006 Dirty Acres Cali Grille Insert for Jeep Wrangler JK 2007-2017 Moab Off Road Park Decal. Begin your Shopping Experience at Sears. Buy Online, Pick up in Store. Find Store Locations. Find Great Brands such as Kenmore, Craftsman & Diehard. Bids in Pennsylvania . Welcome to Pennsylvania Bid. 02/24 Cutting carbon seat post I am going to replace the dropper seat post on my wifes Specialized Rumour mountain bike. She wants me to fit a lighter carbon post as.When the metal changes shape permanently, it is said to . This property is strength. Stiffness. Stiffness affects the riding qualities of a bike frame, since a frame suffers no permanent deformation in normal riding. All kinds of steel, for instance have basically the same elastic modulus. Strength. Strength relates to the crash- worthiness or general durability of a frame, but has no effect on the riding properties. This is called . Although your bike may have a sticker saying . It doesn't matter though, as the table only makes comparisons - - John Allen. For instance, all steels, from the . Supplier and stockists for Api pipe, Api 5L pipe, API Pipes, API 5L Pipes, api seamless pipes, api seamless pipe, api welded pipe, api seamless pipes, api welded pipe. Survival Center Underground Shelters are America's oldest most experienced shelter builders. Professionally engineered and manufactured to exacting standards. This article will discuss frame alignment and the use of the FAG-2 Frame Alignment Gauge. Hello, and thank you for visiting my sitea personal tribute dedicated to the finest American automotive creation in history: the wonderful Jeep Grand Wagoneer. Stiffness is mainly related to the tubing diameter. Strength is mainly related to the wall thickness, though diameter also enters into it. Weight is affected both by diameter and wall thickness. A frame manufacturer can make trade- offs by selecting different tube diameters/wall thicknesses, allowing a frame to be made stiffer, or stronger, or lighter. Steel vs Titanium. Look at the chart again. You'll see that identical steel vs titanium frames would be about equal in strength, but that the titanium frame would be about half the weight and half the stiffness. To compensate, builders of titanium frames use somewhat larger diameter tubes to bring the stiffness more into line with what riders like. This tends to increase the weight a bit, but by making the walls of the larger tubes a bit thinner, they can compensate to some extent, and come up with a frame that is still lighter than a normal steel frame. Steel vs Aluminum. The situation with aluminum is even more pronounced. Such a frame would be quite unsatisfactory. That's why aluminum frames generally have noticeably larger tubing diameters and thicker- walled tubing. This generally results with frames of quite adequate stiffness, still lighter than comparable steel ones. You could build a steel frame with 2- inch diameter tubing, and it would be stiffer than anything available- -indeed, stiffer than anybody needs. By making the walls of the tubes thin enough, you could make it very, very light as well. Two reasons. The thinner the walls of the tubing, the harder it is to make a good joint. This is one reason for butted tubing, where the walls get thicker near the ends, where the tubes come together with other tubes. In addition, if the walls get too thin, the tubes become too easy to dent, and connection points for bottle cages, cable stops, shifter bosses and the like have inadequate support. Let's look at it from a couple of different directions. Torsional/lateral stiffness. This is mainly related to the stresses generated by the forces you create from pedaling. Any frame will flex around the bottom bracket a bit in response to pedaling loads. This flex can be felt, and many riders assume that it is consuming (wasting) pedaling effort. Actually, that's not the case, because the metals used in bicycle frames are very efficient springs, and the energy gets returned at the end of the power stroke, so little or nothing is actually lost. While there is no actual loss of efficiency from a . This is more of a concern for larger, heavier riders, and for those who make a habit of standing up to pedal. A frame that is too flexy in the top tube, head tube and seatstays will feel . Some of this flex is in the luggage rack itself, but there can be enough flex in the frame to aggravate this condition. Vertical stiffness. Since this article deals with frames, the issue at hand is road shock transmitted from the rear tire to the saddle. Ride qualities experienced at the handlebars are to a large extent determined by the fork, as well as geometry, and flex in other bolt- on parts, but are unrelated to the choice of frame material.). Much of the commonplace B. S. It will be said that one frame has a comfy ride and absorbs road shocks, while another is alleged to be harsh and make you feel every crack in the pavement. Virtually all of these . All these parts deflect to a greater or lesser extent when you hit a bump, but not to an equal extent. The greatest degree of flex is in the tire; probably the second greatest is the saddle itself. If you have a lot of seatpost sticking out of a small frame, there's noticeable flex in the seatpost. The shock- absorbing qualities of good- quality wheels are negligible.. The seat stays (the only part of this system that is actually part of the frame) are loaded in pure, in- line compression. In this direction, they are so stiff, even the lightest and thinnest ones, that they can contribute nothing worth mentioning to shock absorbency. The only place that frame flex can be reasonably supposed to contribute anything at all to . Even this compliance is only a fraction of the flex of the exposed length of the seatpost. The frame feature that does have some effect on road shock at the rump is the design of the rear triangle. This is one of the reasons that touring bikes tend to have long chainstays - - they put the rider forward of the rear wheel. Short chainstays give a harsh ride for the same reason that you bounce more in the back of a bus than in the middle.. Ringing, Damping and Suspension. You can hear a metal tube ring if you tap it with a fingernail, but resonances below the audible range most affect the feel of a bicycle. For example, . This is generally worse with a taller frame, because the front triangle is less stiff in torsion, and the resonant frequency is lower. Resonances also can affect the feel when going over bumps. Two frames which are equally stiff may feel different if they resonate at different frequencies. Damping is the tendency of ringing to die out. All metal frames have very low damping - - they ring long enough to produce a clear tone. A carbon- fiber frame will give a dull sound if tapped, because carbon fiber has more damping than metal. This may affect the feel to some degree, though much less at the low frequencies which affect frame feel. Rubber, leather and flesh are highly damped - - and so the greatest damping in a bicycle/rider system by far is in the tires, the saddle and the rider's body, unless the bicycle has suspension. A suspension fork or frame is a highly- damped resonant system - - if it weren't damped, it would bounce up and down repeatedly after every bump. Suspension, obviously, has a major effect on the feel of a bicycle. Suspension also adds weight, affecting the feel. Modern bicycle suspensions are mostly rather stiff, intended to protect the rider and bicycle against hard impacts, while minimizing . Interestingly, recent research published in Bicycle Quarterly magazine showed that tire choice and tire pressure achieved a much greater difference in comfort than a suspension front fork in a test ride on a bumpy surface! The main reason is that: the unsprung weight of the small part of the tire that flexes is tiny, while that of the wheel and fork is substantial. The rider is not rigidly connected to the bicycle, and so the sprung weight is largely that of the frame and attached components. Where Comfort Comes From. If you're looking for a comfortable ride, it is a mistake to focus on the particular material used to build the frame. There are differences in comfort among different bikes, but they are mainly caused by. Tire choice. Wider, softer tires make more difference to ride comfort than anything to do with the frame. Unfortunately, many newer sport bikes are poorly designed when it comes to tire clearance. For the last decade or more there has been a fad to build frames with very tight tire clearance, although there is no performance advantage whatsoever to such a design. Such bikes cannot accept anything but super skinny tires, and, as a result, there's no way they can ever be really comfortable. See my Article on Tires. Saddle choice. See my Article on Saddles. Frame geometry. Generally, frames with longer chainstays, and less vertical seat- tube and head- tube angles are more comfortable. This doesn't make them any slower, but may reduce maneuverability (also known as twitchiness.)Rider positioning and technique in riding over bumps. See my Article on Pain and Cycling. Suspension, if the bicycle has it. A sprung saddle or suspension seatpost also can make a big difference. Also, don't be obsessed with weight. The pound or so of difference between a cutting- edge ultralight frame and a well- constructed, heavier one (generally a steel frame) is important to a racer climbing a mountain pass but makes little difference to a bicycle tourist - - especially not when carrying a touring load. The heavier frame may actually be more comfortable, because it increases the ratio of sprung to unsprung weight, and because it also is stiffer. A steel frame with plain- gauge tubing may actually be preferable for touring, compared with an equally- strong frame with butted tubing, because of the greater torsional stiffness and reduced tendency toward speed wobble when carrying a load. Carbon Fiber. Carbon fiber is an increasingly popular frame material, but it is fundamentally different from metal tubing as a way to construct frames. Because of the fibrous nature of this material, it has a much more pronounced . Alfa Laval - Gasketed plate- and- frame heat exchangers. Gasketed plate- and- frame heat exchangers provide efficient heat transfer in compact equipment with a small footprint. The units have a flexible design and are easy to service and maintain. The product range is extremely wide and is used in duties for heating, cooling, heat recovery, evaporation and condensation in industries ranging from HVAC, refrigeration, engine cooling, dairy and food to heavier processes like chemical processing, oil production and power generation.
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