Shimano Deore XT

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Deore-XT rear derailleur RD-M750, 9-speed
XT cantilever brakes with center pull (1990s)
Seat post XT SP M730

The Deore XT is a group of bicycle components from the Japanese manufacturer Shimano . It is offered by the manufacturer as a high-quality mountain bike group that controls the entire gear and drive system on mountain bikes as well as their brakes and hubs . The Shimano XT groupset was Shimano's top groupset until the Shimano XTR was introduced in 1992. The functionality of the components of the group is largely identical to that of the XTR; the higher price of the XTR components is due to their lower weight, achieved through components made of carbon fiber reinforced plastic and titanium .

history

The Deore -XT group has been available since 1983. With it, Shimano expanded its range of components for mountain bikes. The 6-, 7- and 8-way groups are compatible. From the 9-speed groups onwards, compatibility is no longer given due to the changed spacing between the sprockets on the cassette. A deore 12-speed group with a new freewheel standard has been on the market since 2019.

Series

The group is identified by model numbers M7xx; starting with M700, since 2015 conversion to a four-digit type designation starting with M8000.

M700 from 1982

The group, also known as "Deerhead" (deer head logo on the components), was the first dedicated mountain bike group. It contained all parts that are necessary for shifting, driving and braking an off-road bike. The components stood out somewhat from the touring components previously used for the first mountain bikes and were built to be more robust. The group consisted of a derailleur, rear derailleur, brake lever, gear lever as a thumb switch or frame gear lever, high flange hubs for freewheel, 6-speed cassette , headset , cantilever brakes , crankset with three chainrings and pedals.

M730 / 732/735 from 1987 6/7 speed

A modernization of the group begins, starting with the model name M730. Thumb switches are retained, brakes are made a little more compact, the crank arms are a little stronger. The hubs are equipped with a low flange and a freewheel for cassette sprockets. A demountable bottom bracket (M730) and later a cartridge bearing (BB-UN70) are offered. A headset, a seat post, pedals, a chainstay protector (Shark Fin) are also included.

With the first facelift in 1989, innovations were introduced, some of which are still part of the Shimano groups today. This includes Hyperglide sprocket sets from 7-fold with embossed climbing aids, which make shifting under load possible with a matching chain. There was also the first generation of the Rapidfire STI shift / brake lever combination, still with separate levers for upshifting and downshifting in push-push mode.

After the model upgrade in 1992 (M735), the STI were offered as Rapidfire Plus (switch to push-pull mode) and there was a cartridge bottom bracket that could no longer be dismantled and was not adjustable, which has since formed the standard for all Shimano square bottom brackets.

M737 1993 8-fold

In 1993 Shimano redesigned the groupset to make it lighter and more efficient. The crankset of the M737 generation, still with a square bottom bracket standard, has been converted to a compact bolt circle (94 mm Hyperdrive C) and a lower Q-factor (sum of the distances between the outer surfaces of the cranks and the center plane of the wheel) can be achieved through a stronger offset . The hubs will be converted to the Parallax standard analogous to the XTR M910, and here, too, spider arm pinion sets with 8 pinions will be introduced. The brakes remain in cantilever design, but are lighter and leaner (low-profile system). The shift brake levers are still Rapidfire Plus, now with 24 gears. Shift levers are also offered individually to enable the installation of the colorful anodized CNC-milled brakes that were emerging at the time, as well as hydraulic systems from Magura, which were rapidly emerging at the time. The rear derailleur is equipped with SIS (Shimano indexed system), which offers a new quality of gears. The gearshift reacts more precisely and smoothly than the previous models. For the first time, SPD pedals are being offered that allow a firm, but quickly detachable, binding of shoe and pedal. Also on offer are the headset and seat post, each unchanged.

M739 1995 8-fold

The group was essentially left the same, only the brakes were converted to the then new V-brake system , which was introduced when the Shimano brakes were not able to compete with the increasing competition. The growing popularity of mountain biking and the associated competitions with accompanying reports in the relevant media increased the pressure to innovate on many manufacturers and accelerated the development of new products. With Grip Shift (SRAM), a high-quality alternative to Shimano came onto the market, and many small manufacturers were also pushing into the parts market.

The newly introduced V-brakes offered a significant increase in braking power and were later offered by other manufacturers. Shimano claims to have developed the brakes themselves, but Florian Wiesman had similar brakes in Germany a year earlier. The brakes from Shimano were equipped with parallelogram- guided brake pads, which was a unique selling point. Problems quickly arose, however, because the parts of the lining guide loosened under load and the brakes began to squeal. Therefore the first series was recalled and improved.

M750 1999 9-fold

The color scheme in black and silver remained, the silver is matt from this vintage. Newly added 9-speed sprockets, thus 27 gears, STI minimally changed in design, the V-brakes made much more stable. The Holowtech crankset and the associated Octalink 1 bottom bracket were new. The rear derailleur is externally changed, technically largely the same with an extended swivel range. For the first time, there was a derailleur for bottom bracket mounting to serve the full-suspension mountain bike market. Shift and brake levers can be ordered as a unit or individually. Although other manufacturers already offered disc brakes, Shimano stuck with mechanical rim brakes. Shortly before the end of production, disc brakes with four pistons that still have 6-hole mounting are offered under the designation M755.

M760 2003 9-way

In 2003 a similar group with disc brake option from Shimano came onto the market for the first time. The scope will be expanded significantly and the V-brakes will continue to be offered, parallel to this there are the disc brakes with Centerlock discs and hydraulic actuation. The two brakes are controlled either via separate shift and brake levers or with Dual Control shift brake levers. The V-brakes still have a parallelogram, disc brakes have two pistons.

The crankset is manufactured in the Holowtech 2 standard, for the first time with an external inner bearing and a continuous 24 mm hollow shaft. There were triple chainrings throughout. For the rear derailleur, the inverse option was offered, which falls on the largest instead of the smallest chainring when idle. This option is retained over two generations, as is the dual control switching logic. The front derailleur is also offered as a dual pull so that both types of pull can be operated with one derailleur.

The M760 group remained competitive for a relatively long time and five years in production. Due to the numerous options, the market could be served over long distances, and the new disc brakes were perhaps not always up to the competition's systems in terms of design and braking power, but were far superior in terms of price and performance, and operation and maintenance were also for laypersons understandable and can be mastered with little effort and tools.

M770 2008 9/10 speed

The size of the group remained almost the same, the design was streamlined a little and the lines drawn more sharply. The parts were still in black and silver. The disc brake was redesigned and gained in performance, it was even used in the Downhill World Cup. The crankset became a bit slimmer, with the Q-factor remaining 184 mm, external bottom brackets were standard. For the time being, mechanical and hydraulic dual control brake levers were offered, but these will expire within the model cycle. Hubs came with an aluminum axle and are available in silver and black, as well as a 20 mm thru-axle hub.

Within the generation, the leap to 10-speed sprocket sets was made, along with newly designed Shadow rear derailleurs (M772), which on the one hand could also operate larger cassettes and required significantly less manual force. The new sprocket sets fit all Shimano 8/9/10 speed freewheels, which remain unchanged up to the m8000 group. The slightly more simply designed V-brakes and pedals were also on offer.

M780 2011 10-fold

After just three years there was the next generation. The group was produced in black, only a few parts remained silver or chrome-plated. The Dyna-sys system was introduced for the switching components, which should enable less manual force and more precise switching processes. The group offered 3 × 10 gears, later also 2 × 10. The shift quality remained on par with that of the competition, the brakes in new design became the benchmark in the volume market. Competitors struggled with long-term durability, but the XT brakes worked quite well and were used a lot. The maintenance of the brakes was simplified with the new design and was also feasible by the user with little effort.

At the same time, a group developed for high-quality trekking bikes was offered under the name T780 (2011 10-speed). The main differences were the gear ratios offered and the brake levers equipped with longer levers.

M8000 2015 11-fold

The group, introduced in 2015, is the biggest change of the Shimano XT so far. The orientation towards the Shimano XTR is clear. The parts often look almost the same or similar (apart from the black paintwork). According to commentators, the function of the XT components should be the same and better than that of the XTR group for a long time. This is attributed to the more solid and heavier components of the XT group, which wear out less quickly. Numerous options are offered, including 1 to 3-way cranks, 3 sets of gear levers, 12 front derailleur models, 5 cranksets, 2 rear derailleurs, two bottom brackets (HT II and Pressfit), three cassettes with a total of 11-46 teeth. Two and four piston brakes and hubs for different standards. The group covers all common types of mountain biking.

M8100 2019 12-fold

In 2019, the Shimano XT was presented as a 12-speed group for the first time. It is available as a 1x12 and a 2x12 drive, each with the new freewheeling standard Micro-Spline, which allows pinions with 10 teeth. The group also includes two- and four-piston brakes as well as hubs and wheels.

Web links

Commons : Shimano XT  - collection of images, videos and audio files

Individual evidence

  1. a b Shimano Deore XT derailleur (M700 1st style) . ( disraeligears.co.uk [accessed June 25, 2018]).
  2. a b Tobias Brehler: Shimano SLX and XT gears now 12-speed! In: bike magazine. May 30, 2019, accessed June 21, 2019 .
  3. Model Number RD-M780 ( Memento from November 5, 2012 in the Internet Archive ) shimano.com November 5, 2012 (English).
  4. First Shimano XT group in 1984
  5. Thomas: Shimano Deore XT - M735 - retro-mtb.de. Retrieved on July 10, 2018 (German).