{"product_id":"shimano-dura-ace-di2-br-rs9170-flat-mount-hydraulic-disc-brake","title":"Shimano Dura-Ace Di2 BR-RS9170 Flat Mount Hydraulic Disc Brake","description":"\u003cdiv\u003e\n\u003cp\u003eThe \u003cstrong\u003eShimano Dura-Ace BR-RS9170 Flat Mount Hydraulic Disc Brake\u003c\/strong\u003e is Shimano's flagship road disc caliper — smaller and lighter than its predecessors, yet engineered to shed heat faster and stop harder. The dual-piston design has been refined for a sharper balance of braking power and modulation, with pistons that self-adjust and retreat farther from the rotor to prevent rub caused by minor frame flex or imperfect wheel seating.\u003c\/p\u003e\n\n\u003cp\u003eThe lower-profile caliper sits tighter behind the fork and stays, reducing its wind footprint without compromising feel. Chamfered pad edges guide rotors in cleanly, and the gravity-bleed system makes maintenance straightforward — open the valve and the fluid does the work. These calipers mount via Shimano's flat mount standard and are sold individually; specify front or rear at checkout. Hydraulic hose and fluid are not included with the caliper alone — if you purchase compatible levers separately, hose and fluid are typically included with those. Rotors are sold separately; Shimano's SM-RT900 is the recommended pairing, available in 140mm and 160mm.\u003c\/p\u003e\n\n\u003ch3\u003eShimano Dura-Ace BR-RS9170 Specs at a Glance\u003c\/h3\u003e\n\u003cul class=\"specs_at_a_glance\"\u003e\n  \u003cli\u003eMount standard: Flat mount\u003c\/li\u003e\n  \u003cli\u003ePiston configuration: Two-piston hydraulic\u003c\/li\u003e\n  \u003cli\u003eWeight: Approx. 256g per caliper (515g per pair)\u003c\/li\u003e\n  \u003cli\u003eRotor compatibility: 140mm or 160mm (sold separately)\u003c\/li\u003e\n  \u003cli\u003eAvailable as: Front or Rear (sold individually)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e","brand":"Shimano","offers":[{"title":"Black \/ Front","offer_id":43520053575724,"sku":"IBRR9170F1RF","price":179.99,"currency_code":"USD","in_stock":true},{"title":"Black \/ Rear","offer_id":43520053608492,"sku":"IBRR9170R1RF","price":174.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0608\/7684\/9196\/files\/shimano-dura-ace-di2-br-rs9170-flat-mount-hydraulic-disc-brake-2784796.jpg?v=1771297990","url":"https:\/\/ricycles.com\/products\/shimano-dura-ace-di2-br-rs9170-flat-mount-hydraulic-disc-brake","provider":"RA Cycles","version":"1.0","type":"link"}