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1989 Diamond Back Ascent EX

a large 1989 Diamond Back mountain bike with smoke lilac colorway leans against a garden wall. The bike has BMX bars, knobby 26" tires, pads on the bars and top tube with colorful pink donut and pizza patter, and a brown handlebar bag 1989 Diamond Back Mountain Bike Catalog page featuring the Ascent EX.

A $40 online classifieds find, in ok shape. Mostly original but it has a Weinmann 519 rear rim on a bolted hub, and a Deore II front derailleur, and newer Tourney lever shifters

1989 Diamond Back Ascent EX Build Specs

Weight: ?lbs, fairly light

Frame: 1989 22.5" Tange MTB double-butted CrMo, Dualtone Blue Smoke/White colorway. Serial XXXXXXXXX

Fork: 100% CrMo UniTrac with straight oversize taper blades

Cockpit

Handlebars: Diamondback alloy 0° rise, 10° sweep, 1"/25.4mm.

Grips: DB

Stem: Tioga T-Bone 22.2mm / 1" quill stem, maybe 6°?

Headset:

Saddle: Mongoose. Originally Avenir RacingGel Lycra

Seatpost: Delta DP 300mm

Seat Collar: DB QR

Shift/Brake Levers: Shimano ST-EF29-L (L) Shimano ST-EF29-7 (R). Originally Shimano Exage Mountain LX 3x7 SL-M453 + BL-M451 ???

Pedals: originally Diamond Back alloy body/cage

Brakes

Brakes: Shimano BR-M454 Canti (F/R)

Pads:

Drivetrain

Bottom Bracket: Shimano cartridge?

Chain:

Crankset: Shimano Exage Mountain LX, 175mm, 46/36/26t FC-M452

Cassette: 6-speed ?-28t (Originally Shimano Mountain LX 7-speed 13-30t)

Front Derailleur: Shimano Deore II FD-MT62 3x

Rear Derailleur: Shimano Mountain LX RD-M462 x7

Wheelset

Hubs: Shimano Mountain LX HB-M451 (F) / R (originally Shimano Mountain LX FH-M452 rear)

Rims: Araya RX-7 (F), Weinmann 519 (R) (originally Araya RX-7 both)

Tires: Kenda 26x1.95" (F/R) (originally Tioga Farmer John Cousin 26x1.95" F/R)

1989 Diamond Back Mountain Bike Catalog page featuring the specs for the Ascent EX.

Original catalog specs page

Component weights:

Wheelset: ? (F), ? (R)

Frame Geometry (22.5")

spec sheet + some of my measurements

Seat Tube (C-T): 22.5" (572mm)

Seat Tube (C-C): 21.5" (546mm)

Top Tube, Actual: 23.2" (590mm)

Head Tube Angle: 70º

Seat Tube Angle: 73º

Chainstay Length: 16.9" (430mm)

Headtube Length: X" (XXXmm)

Bottom Bracket Drop: X" (Xmm)

Bottom Bracket Height: 11.8" (300mm)

Standover Height: " (mm)

Front Center: X" (XXXmm)

Wheelbase: 42.9" (1089mm)

Stack: XXXmm

Reach: XXXmm

Fork Rake: 1.77" (45mm)