Park Tool TM-1 Spoke Tension Gauge
Park Tool’s TM-1 spoke tension gauge takes the guesswork out of wheelbuilding. Achieving correct spoke tension when building or truing a wheel is critical. Deciding what actually is
the correct spoke tension, however, is a moving target that depends upon the spoke design, the strength of the rim and the amount of offset or ‘dish’ in the wheel to make room for disc brakes or the rear wheel’s cassette. Park’s TM-1 spoke tension gauge is designed to measure the tension of individual spokes, but it goes further, by including a guide that suggests correct spoke tension ranges for the most popular spokes, as well as a handy key with calibrated slots with which to assess the thickness of spokes. The TM-1 is calibrated for life (return it to the factory if you bungle the mech’) and is backed with its own web page that offers tutorials and a continuously updated list of spoke and wheel maker’s tension recommendations. Park notes that the TM-1 is designed for home mechanics as well as pro shops and goes out of its way to make this technically oriented tool as understandable as possible. The TM-1 costs around $60 USD At better bike shops. Park Tool
Park Tools TM-1 is sold with a spoke-thickness gauge, spoke-tension/spoke-type chart and detailed instructions.
|Park's TM-1 spoke tension gauge is absolutely simple to use: simply squeeze the handles, place its three pins in the middle of a spoke, release and then read the number the arrow points to on its mechanical display. The number is not the actual spoke tension. It is a reference number that one then matches up with the diameter of the spoke in Park's included chart to determine the tension. The previous two steps afford garage mechanics with enough information to true or even build a wheel. Park's detailed explanation, however, insists that each wheel has an ideal spoke tension and that one should contact the rim and spoke maker to ensure a perfect wheel. Fortunately Park's TM-1 page and some uber-informative sites, like DT Swiss, compensate for the on-line vacuum left by some wheelmakers. I found everything I needed on the TM-1 page. TM-1's trail to a perfect wheel gets a bit confusing if you are not a numbers person, with various equations and numerical ranges which are used to assess average spoke tension. All of which can be ignored with two suggestions: Rule one - spoke tension on one side of the wheel can vary up to 20 percent. Magically, the difference between each number on the TM-1's readout is about 20-percent, so if the gauge says '25' just make sure that none of the other spokes reach 24 or 26. Rule two - Measure and jot down the spoke tension of your wheels when they are new (each side of the wheel) or use the TM-1 to measure the same model wheel at your LBS and simply use the TM-1's readout to tune your wheels instead of bothering with simple math or the conversion chart. Those who tune or build wheels often will discover that Park Tool's TM-1 is an invaluable tool. - RC|
Avid Elixir 5 Disc Brake
Continuing on the affordable performance theme, Pinkbike tests Avid’s mid-priced Elixir 5 disc brake. ‘Elixir’ brakes all share Avid’s Taperbore master cylinder design, which replaces the seal-destroying side ports most systems use with a smooth, stepped taper. When the piston retracts beyond the taper section, brake fluid can replenish the system. When you squeeze the brake lever, the brake actuates the instant the piston reaches the end of the taper in the master cylinder. Elixir 5 brakes feature every pep of the top-line Elixir 9 brake, except the carbon fiber lever, pad-contact adjust and the sintered metallic pads. In specific terms, the 5’s have Avid’s two-piece, twin-piston caliper; Tri-Align, post-mount attachment hardware; one-finger lever ergonomics; tool-free lever-reach adjustment dial; omni-directional lever clamp; and SRAM’s integrated shift/brake lever ‘Matchmaker’ compatibility. All Avid hydraulic brakes use DOT 5.1 fluid. Elixir 5 brakes offer a full gamut of six-bolt rotors, from 140 to 200 millimeters. The weight of a post-mount front brake assembly is close to 390 grams (with a 160mm rotor). Compare that to the $260 carbon-lever X.O brake at 333 Grams and the ‘5 starts to look pretty good for around $120 USD per side. Avid Brakes
(clockwise) Avid Elixir 5 levers share the same one-finger-braking profile of Avid's elite level X.0 brakes. The lever-reach dial is hidden in front of the lever pivot and can be rotated with a small Allen wrench. Split clamps and a bi-directional casting allow Elixir levers to be flip-flopped. Top-loading brake pads are plus, the Tri-Align post-mount system is debatable. With perforated, wavy rotors, the Elixir 5 brake looks as well as it performs.
|Avid's Elixir 5 brakes deliver smooth, easy to modulate braking without feeling grabby, even after hard, rotor-burning technical descents. Lever ergonomics are a bit behind the times when compared with Shimano's new shorty blade and the comfortable shape of Magura's latest offerings. Still, we arrived at the bottom of each downhill without hand fatigue, which is job-one for any brake lever. The organic pads in the -5 calipers give up some stopping authority over the sintered metallic pads we have enjoyed on Avid's upper-end brakes, but the exchange is that the -5 Elixirs run, without the buzzing that the X.0 and cousins often emit. Top-loading pads make for easy replacements and the Avid bleed system is one of, if not the easiest to use. We question the lever-reach-adjust barrel, which can be turned by strong fingers, but is designed to be manipulated via a small Allen wrench like a windlass on a 16th century sailing ship. It works, though, and is an adjustment that most only do once. Avid prides itself on its Try-To-Align semi-hemispherical washer system, that in its idealized form, allows the caliper to seek perfect alignment between the brake pads and the rotor faces - which occurs about 50-percent of the time. Lose the lottery, though, and the simple act of tightening the mounting screws will skew the caliper, cause the pads to drag, and make seasoned mechanics cry. Our Elixir 5 brakes bolted up drag free the first time, however, and thus we heartily recommend them to anyone on a budget who is searching for top-level braking performance. - RC|
Mavic CrossMax SX Wheels
Mavic CrossMax SX Wheels are designated for Enduro racing and all-mountain applications, and have been seen in a few Pinkbike tech features. The highlights of this beautiful looking wheelset begin with a 21-millimeter ID rim profile that is a true UST tubeless design. The oversize, round spokes are Mavic’s ‘Zicral’ aluminum, paired with straight-pull hub flanges. Mavic uses 24 spokes on both front and rear wheels, with a two-cross pattern up front and with the rear wheel, two-cross on the left and one-cross on the drive side. The front hub is available in 15QR or 20-millimeter and is easily convertible. The rear hub is convertible from standard quick release to 142/12 and 12/135 millimeter through-axles. Mavic upgraded its entire CrossMax line with the stronger, more responsive four-pawl ITS-4 ratchet mech. Two pawls engage in unison and the ITS4 mech is said to be 60-percent quicker to engage. SX hubs fit six-bolt rotors only and the rims are certified for tires up to 2.5 inches wide. The rear hub bearings are adjustable for free play, which is good, and the wheelset comes with a full compliment of extras like: 15mm and 20mm through-axle adapters for the front hub; a 12mm through-axle adapter for the rear hub; a rear quick release, spoke wrenches, bearing adjustment wrenches and tubeless valve stems. Weight is darn close to Mavic’s stated 1755 grams in the 15QR/142/12mm configuration and the price is around $850 for the wheelset. Mavic
(Clockwise) The CrossMax SX wheels are the jewel in Mavic's trailbike/AM crown. The SX rim is a true UST tubeless profile with a reconfigured U-shaped well that causes the tire to air up easier. Straight-pull Zicral aluminum-alloy spokes nest into the spoke flanges.
|There is much to love about Mavic's CrossMax SX wheelset. It has withstood the test of time on Pinkbike's tire-testing bikes, and after a year, the wheels still look stunning, the tension is even and the rims run straight. Best of all, every UST tubeless or tubeless-ready tire we have mounted has popped on with a hand pump. With a 21mm ID rim profile, the SX rim gives new life to old-school tire designs with more responsive cornering and a broader footprint for climbing and braking. Add Mavic's convertible axle hub design to the wheel's sharp performance and the Crossmax SX is a go-to for anyone in the market for a lightweight wheelset for Enduro racing or technical trail work. The Crossmax SX may be Mavic's best design in its entire trailbike lineup. - RC|