Engineering:Shimano Deore XT

From HandWiki

Deore XT is a mountain and touring bike groupset first introduced by Shimano in 1983.[1] It was Shimano's first mountain bike groupset, based on their existing Deore touring groupset, and it consisted of a triple-, double- or single chainring crankset, front and rear derailleurs, handlebar-mounted "finger" shifters, cantilever brakes, and large-flange hubs.[1] Since then, it has become their "second-tier" offering, the list of components has expanded to include hydraulic disc brakes, a complete wheelset, a chain, and clipless pedals,[2] and it is offered in silver or black finish.[3]

Model history

The groupset was designated by model numbers M7xx; beginning with M700,[1] and ran to M780.[4] Touring groupsets were designated by model numbers T7xx. Current groupsets are designated by model numbers M8100 and T8000.

  • M700 1983 friction (Deer Head)
  • M730 1987 6-speed
  • M732 1989 7-speed
  • M735 1992 7-speed
  • M737 1993 8-speed
  • M739 1995 8-speed
  • M750 1999 9-speed (first groupsets sold already in 1998, these sets are code-stamped WK onwards)
  • M760 2003 9-speed
  • M770 2008 9/10-speed
    • Rear derailleur: introduction of Shadow low-profile design, which reduced the risk of damage from side hazards. Shimano has released four models of rear derailleur in M770 lineup:
      • RD-M770, 9 speed, reversed spring
      • RD-M771, 9 speed
      • RD-M772, 9 speed, Shadow profile
      • RD-M773, 10 speed, Shadow profile
    • Front Derailleur:
      • FD-M770, 9 speed
  • M780 2011 10-speed
    • Shifting Lever:
      • SL-M780-B-IR, 10 speed, I-spec B
      • SL-M780-B-IL, 2/3 speed, I-spec B
      • SL-M780-R, 10 speed, clamp band
      • SL-M780-L, 2/3 speed, clamp band
    • Front Derailleur:
      • FD-M785, 2 speed, clamp band, top swing, dual-pull
      • FD-M785-E2, 2 speed, e-type, top swing, dual-pull
      • FD-M786, 2 speed, clamp band, down swing, dual-pull (top-pull exclusive)
      • FD-M786-D, 2 speed, direct mount, down swing, dual-pull (top-pull exclusive)
      • FD-M780-A-B, 3 speed, clamp band, top swing, dual-pull
      • FD-M781-A-B, 3 speed, clamp band, down swing, dual-pull
      • FD-M781-A-D, 3 speed, direct mount, down swing, top-pull
      • FD-M780-A-E, 3 speed, e-type, top swing, down-pull
    • Rear derailleur: introduction of Shadow Plus technology, which added a switchable clutch used to stabilize chain tension. Shimano has released two versions of the rear derailleur - M781 (without clutch) and M786 (with clutch). Both versions were sold in two cage length options - GS (medium) and SGS (long, 95 mm between centres of jockey wheels axis).
      • RD-M781-SGS, 10 speed, Shadow, long cage (total capacity 43T)
      • RD-M786-SGS, 10 speed, Shadow Plus, long cage (total capacity 43T)
      • RD-M781-GS, 10 speed, Shadow, medium cage (total capacity 35T)
      • RD-M786-GS, 10 speed, Shadow Plus, medium cage (total capacity 35T)
    • Brake Lever:
      • BL-M785-B, hydraulic disc brake, open clamp band, compatible with I-spec B
  • T780 2011 10-speed
  • M8000 2015 11-speed
    • Shifting Lever:
      • SL-M8000-R, 11 speed, clamp band
      • SL-M8000-L, 2/3 speed, clamp band
      • SL-M8000-IR, 11 speed, I-spec II
      • SL-M8000-IL, 2/3 speed, I-spec II
      • SL-M8000-B-IR, 11 speed, I-spec B
      • SL-M8000-B-IL, 2/3 speed, I-spec B
    • Front Derailleur:
      • FD-M8000-D, 3 speed, direct mount, side swing, front-pull
      • FD-M8000-E, 3 speed, e-type, side swing, front-pull
      • FD-M8000-H, 3 speed, high clamp band, side swing, front-pull
      • FD-M8000-L, 3 speed, low clamp band, side swing, front-pull
      • FD-M8020-D, 2 speed, direct mount, side swing, front-pull
      • FD-M8020-E, 2 speed, e-type, side swing, front-pull
      • FD-M8020-H, 2 speed, high clamp band, side swing, front-pull
      • FD-M8020-L, 2 speed, low clamp band, side swing, front-pull
      • FD-M8025-H, 2 speed, high clamp band, down swing, dual-pull (top-pull exclusive)
      • FD-M8025-L, 2 speed, low clamp band, top swing, dual-pull (down-pull exclusive)
      • FD-M8025-D, 2 speed, direct mount, down swing, dual-pull (top-pull exclusive)
      • FD-M8025-E, 2 speed, e-type, top swing, dual-pull (top-pull exclusive)
    • Rear Derailleur:
      • RD-M8000-SGS, 11 speed, Shadow Plus, long cage (total capacity 47T)
      • RD-M8000-GS, 11 speed, Shadow Plus, medium cage (total capacity 39T)
    • Brake Lever:
      • BL-M8000, hydraulic disc brake, open clamp band, compatible with I-spec II
  • T8000 2016 10-speed
  • M8100 2019 12-speed
    • Shifting Lever:
      • SL-M8100-R, 12 speed, clamp band
      • SL-M8100-IR, 12 speed, I-spec EV
      • SL-M8100-L, 2 speed, clamp band
      • SL-M8100-IL, 2 speed, I-spec EV
    • Front Derailleur:
      • FD-M8100-D, 2 speed, direct mount, side swing, front-pull
      • FD-M8100-E, 2 speed, e-type, side swing, front-pull
      • FD-M8100-M, 2 speed, clamp band, side swing, front-pull
    • Brake Lever:
      • BL-M8100, hydraulic disc brake, open clamp band, compatible with I-spec EV

References

  1. 1.0 1.1 1.2 Michael Sweatman. "Shimano Deore XT (M700 1st style)". Disraeli Gears. http://www.disraeligears.co.uk/Site/Shimano_Deore_XT_derailleur_%28M700_1st_style%29.html. Retrieved 2012-07-20. "A milestone in derailleur history." 
  2. "DEORE XT gets full make-over at 30th birthday". Shimano USA. April 14, 2011. http://bike.shimano.com/publish/content/global_cycle/en/us/index/news_and_info/news/deore_xt_gets_full.html. Retrieved 2012-07-21. 
  3. Richard Tyler (Apr 14, 2011). "New Shimano Deore XT groupset for 2012". BikeRadar. http://www.bikeradar.com/news/article/new-shimano-deore-xt-groupset-for-2012-29882/. Retrieved 2012-07-21. "Shimano roll-out upgrades to their second-tier Deore XT groupset to mark its 30th birthday. The new groupset will be offered in either silver or black." 
  4. "Model Number RD-M780". Shimano USA. 2012. Archived from the original on 2012-08-04. https://web.archive.org/web/20120804014808/http://bike.shimano.com/publish/content/global_cycle/en/us/index/products/mountain/New_Deore_XT/product.-code-RD-M780-SGS-S.-type-.rd_mountain.html. Retrieved 2012-07-20.