Niner  2010 S.I.R. 9 frame

The S.I.R. 9 is the most versatile bike in the Niner stable, fusing the “steel is real” feel of Reynolds tubing with the ability to run the frame as either a geared bike or single speed. The S.I.R. 9 uses the same custom drawn Reynolds 853 tubing as the M.C.R. 9 and combines it with Niner’s ultra-light eccentric bottom bracket. Custom “breezer” style forged dropouts have a replaceable alloy derailleur hanger and come with an insert piece for running the bike as a single speed to eliminate the unnecessary derailleur hanger for a clean look.

Niner’s own EBB, at 100 grams, is the lightest eccentric bottom bracket on the market. In addition to being light, it’s extremely functional. The EBB has more swing than any other EBB, over a full link, so you will never have to hunt down a half link to get correct chain tension and vertical dropouts mean you’ll never have to futz with the disc brake to remove the wheel.

The S.I.R. 9 is truly a do-everything frame. Run it single speed at your local race, then convert it to a full gear set to do the Trans-Alp. Want a 1 x 9? No problem. Or, if you’re just not sure, the S.I.R. 9 will give you the option of trying it all.

• All measurements based on a FOX 80mm travel fork with 44mm rake offset and the EBB in the 6 o'clock position
• 27.2mm seat post, 400mm length recommended
• 73mm bottom bracket shell
• 28.6 front derailleur clamp, bottom pull, low mount (top swing)
• 29.6mm seat clamp diameter

GEOMETRY

	SMALL (IN/MM)	MEDIUM (IN/MM)	LARGE (IN/MM)	X-LARGE (IN/MM)
(A) EFFECTIVE TOP TUBE LENGTH	23.1/587	23.75/603	24.5/622	25.25/641
(B) SEAT TUBE LENGTH	15.5/394	16.5/419	19/483	21.5/546
(C) CHAIN STAY LENGTH	17.3/440	17.3/440	17.3/440	17.3/440
(D) FRONT CENTER	25.3/643	25.8/656	26.5/673	27.3/693
(E) WHEELBASE	42.3/1073	42.7/1085	43.5/1104	44.3/1124
(F) BB DROP	2.8/70	2.8/70	2.8/70	2.8/70
(G) HEAD TUBE LENGTH	3.5/90	3.9/100	4.3/110	5.1/130
(H) SEAT TUBE ANGLE	73°	73°	73°	73°
(I) HEAD TUBE ANGLE	71.5°	72°	72°	72°
STAND-OVER HEIGHT	27.8/706	28.6/728	30.7/780	32.8/832
HEIGHT RECOMMENDATION	5'3"-5'9" 1.6-1.75m	5'8"-6' 1.73-1.83m	5'11"-6'3" 1.8-1.91m	6'3"-6'7" 1.91-2.01m