Tune Tretlager AC38 Titanium: Bottom Bracket

Tune 5

Designed and engineered to be the highest quality JIS square taper bottom bracket ever produced. Manufactured with an unrivaled level of accuracy to achieve the highest levels of performance and durability.

The AC38 has an oversize grade 5 titanium axle rolling on Tune’s own custom triple hybrid bearings, encased in a precision 7075 T6 aircraft aluminium sleeve. Cranks are tightened onto the axle using unique gold titanium stretch bolts (which elongate with tension to ensure constant pressure between axle and crank), while integrated washers offer increased surface area. No compromises were made when Tune designed the AC38 nearly 16 years ago, years of extreme use in the hands of pro Tour de France and MTB World Cup riders have proven its integrity time and time again.

Simply the best!

Specification
Use: Road & MTB
Cups: CNC machined from seamless 7075 T6 drawn aluminium tubing
Axle: CNC machined from TiAl6V4 titanium billet
Shell: CNC machined from seamless 7075 T6 drawn aluminium tubing
Width: 68 mm or 73 mm (BSA) 70 mm (ITA)
Bolts: M8 x 1 x 46 / CNC machined from TiAl6V4 titanium billet, anodized gold
Spindle lengths: 104 / 107 / 110 / 113 / 117 mm
Spindle Diameter: 17 mm
Spindle type: Industry standard (JIS 2°) square taper
Cup threads: BSA 1.37° x 24 (British thread) / ITA 36 x 24 (Italian thread)
Bearings: 2 x radial (61903) 1 x angular single-row hybrid cartridge bearings (61803)
Seals: Steel dust seals + rubber lip & labyrinth seals
Weight (Bottom Bracket): From 145 grams
Weight (Bolts): Approx. 27 grams a pair
Price: £183.00

The Tune W2 tool is required to fit this item correctly (Not included) Click to view >>

Posted By — Andy @ 2:50 pm —

No Comments »

No comments yet.

Leave a comment

RSS feed for comments on this post.
TrackBack URI