Triathlon-Räder und Leichtbau: So speckst du dein Rad sinnvoll ab

"...it's better to travel light...", the band Silbermond warbles over the radio every five minutes. That's not the whole truth for triathlon bikes, because on flat courses aerodynamic advantages are more useful than light weight. It's just that the most interesting triathlons rarely take place on flat courses. We will therefore tell you which measures make sense.

Aerodynamics vs. weight

So when is it worth looking at weight instead of looking at aerodynamics? Definitely when it's going uphill.

On many of the most beautiful, spectacular and most demanding routes, there are a lot of meters of altitude to overcome. Think of races like Immenstadt, Norseman, Lanzarote, Alp d`Huez, Silverman, Embrunman, ... just to name a few.

A triathlon bike can still make sense there, but you should keep an eye on the weight here. This becomes even clearer on short trips like in Kitzbühel or at Schliersee. Starting here with the aero wheel and disc wheel is like a 100 meter sprint with moon boots.

In the professional field, it is said that from a gradient of 7-8%, the advantage of a lower weight is more valuable (i.e. it saves more time) than better aerodynamics, which seems logical given the lower speed. In the amateur area, this should even be the case with an incline of 5-6%. And even if most courses eventually go downhill again, the time lost on the mountain cannot be fully made up for.

Uphill passages are not the only sensible area for low weight. Especially with wheels, low weight is very noticeable in the acceleration. On routes with many tight corners, where frequent braking and accelerating is necessary, there is no substitute for light wheels. So where can weight be saved, and where might it be better to keep your hands off it?

Aerodynamics vs. Weight: What's worth it?

The frame

Almost all of the current triathlon bikes/frames are developed for optimal aerodynamic properties. Weight usually plays a subordinate role. Very few manufacturers still specify the weights of their frames. The integration of components such as fork, stem, brakes, etc. usually has a negative effect on the weight, as the construction is much more complex.

If you're looking for a light frame, you should stick to models that don't require a lot of frills, such as the Cannondale Slice.

For hilly races, a road bike frame can also be a good option. Some representatives of this category, such as the Felt AR or the Simplon Nexio, offer either a large adjustment range for the seat post or a special triathlon seat post to achieve a suitable seating position. With their very low weight and handling typical of racing bikes, they are often more than just an alternative.

The fork

Since many frames are delivered with their own matching fork, there is rarely any corresponding tuning potential here. If you can and want to use a classic standard fork, you will automatically end up with the North German company THM when it comes to lightweight construction. The "Scapula" series is the benchmark for all other forks, and with the "Scapula F" even sensible lightweight construction with integrated brakes has been achieved. Most forks do not reach 340 grams including brakes, even without brakes.

The tax rate

With the headset, it is better to pay attention to good bearing quality than to weight, because there is not much to get out of it anyway.

The Stem

Caution is called for when building the stem. On the one hand, not all stems are approved for the use of aero handlebars and, on the other hand, some stems have a handlebar clamp that makes it impossible to mount aero handlebars at all. You should definitely check these points before looking at the weight. Rigidity and safety are definitely priorities. Many good and suitable stems are in the range between 120 and 150 grams. This also applies to many in-house models from the bike manufacturers. Quantum leaps in weight are hardly possible.

The driver

Here the weights differ greatly. But here, too, the fit should receive more attention. The lightest handlebars are useless if you can't ride or lie comfortably on them. If this requirement is met, you can't get past the HAERO H 253 TT SL in terms of weight. At just 350 grams, it weighs less than half that of its competitors and is (like the THM forks) made in Germany.

The seat post

The use of round tuning seat posts is almost impossible for the frames in question, since almost all frames suitable for triathlon are supplied with their own specially shaped seat posts.

The saddle

Ever heard of DASH Cycles? This US company builds minimalist triathlon saddles in a split-nose design (like ISM), and at 85 grams the Tri 7 is probably the lightest triathlon saddle in its range. Handcrafted custom aero seatpost combos are also doable if you have a few bucks to spare. Since there is no sales partner in Germany, they are unfortunately still extremely rare in this country.

The crankset

As with the fork, when it comes to lightweight cranks, you automatically end up at THM. The new "Clavicula SE" crank is not only the lightest, but also (sorry for the word) "AWESOME" crank in the world. The right crank with 30mm axle is made of carbon in one piece, which is unique in this form. 302 grams for the crankset (or almost 500 grams complete with chainrings and bottom bracket) is a record. With a saving of around 200 grams (ie around 30%) compared to a Dura Ace crank, you can really get something out of it. The slightly cheaper "Clavicula" and "Clavicula M3" models are also among the lightest cranks on the market. Since the m³ is compatible with an optional SRM Spider, it is perfect for ambitious athletes who do not want to do without performance measurement.

The inner camp

If there are tuning options for the desired crank with regard to the bottom bracket, it is advisable, as with the headset, to give priority to the bearing quality over the weight.

The switching group

In this case, only the rear derailleur, front derailleur, shifter and cassette are taken into account as part of the switching group, since all other parts can be replaced at least to the same extent. If you add up these four parts, the three major manufacturers are not far apart with their top products. SRAM is the top choice when it comes to weight, and mechanics are lighter than electronics. The mechanical SRAM RED still has the edge in terms of weight, although the lightest SRAM shifter is only suitable for 10-speed drivetrains and all 11-speed versions are heavier.

The brake levers

Even with the brake lever, it will hardly be possible to slim down much. Many models are between 80 and 90 grams per pair. The 3T (60g) and the KCNC (70g) are lighter. Since not all levers fit on every handlebar, you should definitely check the compatibility.

The brake

Even the lightest brakes are a product "Made in Germany". At 120 grams, the AX Lightness 3000 carbon brakes are not even half as heavy as the lightest series brakes (SRAM RED 262g). The THM Fibula is also in the same league as the AX Lightness. Due to their high rigidity, both are also certified as having good braking performance, which is a clear shortcoming for many lightweight brakes. In this regard, the stock brakes are hard to beat. However, there are manufacturers whose brakes combine outstanding braking performance with very low weight, such as the "ee-brake", which is still very light at 200 grams.

The chain

The KMC X 11 SL is considered by many to be the best chain in the world. Hollow rivets and drilled outer plates even save some weight, but that's negligible. Function, running and wear resistance are top, and it is also compatible with all 2*11 switching systems.

The wheels

The wheels are, as always, a very exciting topic. When it comes to lightweight construction, many people think of lightweight first. But there are several far better alternatives, especially for triathletes. The AX Lightness Premium 80T wheels are not only lighter than Lightweights Fernweg, but the price is also within an expected range. The rims built in Germany use a licensed Zipp patent and, thanks to their conventional construction, can be both centered and repaired. The AX Lightness should also be clearly ahead in terms of aerodynamics and handling. Lightweight is only really great when it comes to stiffness. (Perfectly suited if you ride a criterium and have to do a crisp sprint every few laps...)

In the case of light wheels, care must generally be taken to ensure that they are built with the appropriate spoke tension. Especially in the area of ​​front wheel hubs, there are some candidates that cannot tolerate adequate spoke tension. It is of course not possible to build a good and stiff impeller.

However, if you want to use a disc wheel, then the Lightweight Autobahn is again the first choice for low weight. Apart from Lightweight, only Dash Cycles and Citec manage to build a disc wheel that, with less than 800 grams, outshines even many "normal" rear wheels. Lightweight and Dash rely entirely on carbon, while Citec uses the (questionable) combination of aluminum and carbon. This is unbeatable for bumpy courses, and even on real mountain routes there is actually nothing to be said against it. Whether the aerodynamics of a disc are so relevant at a speed of 15 km/h on a steep climb can be doubted. On flat stretches, many drivers complain that these very light disc wheels do not have enough flywheel mass to "march" properly. So think carefully about where you use which material.

The tires

If you're serious about weight then you'll no doubt ride tubular tires. And not because the tires are better or lighter, but because light wheels are ALWAYS for tubulars. A clincher wheel set is generally a lot heavier than a tubular wheel of the same type. Judging a tire by weight alone doesn't make much sense, but if weight is everything (and that's aside from pure track tires) then the TUFO Elite Jet is a real hit at 160 grams, and it's also pretty puncture-proof. With a width of 20 millimeters, you shouldn't expect much comfort.

The quick release

Some of the lightweight quick releases look like identical twins. Thin, minimalist levers on a ball or roller cam. Weights of around 40 grams per set are not uncommon. But there are differences. While the high-quality tensioners are mounted in aluminum or brass joints, you can also see plastic on cheaper models. In addition, some models feel quite soft when closed or even bend the lever. So light is not always good. For the axles, you should rely on steel or titanium. Some manufacturers try to tease out a few more grams with aluminum axles, although aluminum only has around half the tensile strength of titanium and only a quarter of steel. If you not only want to ride uphill but also downhill safely, you should keep your hands off such experiments.

Aluminum or titanium screws

There are a few places on the bike where you can swap the standard steel bolts for lighter bolts. However, due to their lower strength, aluminum screws should only be used where it is not relevant to safety. These include, for example, bottle cage screws or the cable clamps of the gearshift. For brakes, seat posts, stems, etc., it should be at least titanium (which some manufacturers already use as standard on high-quality parts). Of course you can't go wrong with stainless steel screws.

Caution: Replacing screws will void the manufacturer's warranty!

Even if weight is not everything, moving a light bike is much more comfortable. Some German companies that also produce in Germany are among the best manufacturers of lightweight components in the world. Maybe that's a reason to spend a little more money on the next upgrade.

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