Nature Boy

The Nature Boy is our single speed cross racing monster.  It was named after a Minnesota professional wrestling legend and carries all of the AC hallmarks: straight blade fork, classic paint, custom dropouts, and signature headbadge.  It was designed primarily as a race rig, but since we knew that many of you out there would be using it for every day life we built in additional features to make it more versatile. 

You’ll find hidden fender mounts, two sets of bottle bosses (reinforced of course), removeable canti studs, fat tire clearance, and a steel fork that is easily swapped for a carbon model should you want to lighten up for race season. 

The Nature Boy is your new best bro (or brah if you’re from Colorado, where they take cyclocross seriously).  Race the crap out of it, ride singletrack, gravel, or commute until your heart’s content.  Woooooooooooo!


Features

Frame: 100% full 4130 ChroMoly steel. Double butted down, top, and seat tubes. Externally tapered, ovalized, and dimpled chain stays, tapered seat stays.  Brazed on seat collar, reinforced water bottle bosses. 

Fork: 4130 ChroMoly double butted tapered fork blades, lugged crown and matching fork end.  Designed to be interchangeable with most aftermarket carbon forks;  standard cross offset and axle to crown.

E.D. Finish:  The entire bike is E.D. coated inside and out.  E.D. coating not only improves the quality and durability of the paint, but is the best rust proofing agent going.  With the E.D. coating there is no need to Frame Saver the bike, it’s already done for you. 

Internal cable routing:  The internal rear brake routing not only improves the beauty of the frame, but also provides the ultimate in comfort when grabbing the top tube to shoulder the bike.  Once you try it, you’ll wish all of  your bikes (where appropriate) had this feature, and since the entire bike is E.D. coated there’s no worries about the cable channel rusting.

Cross race geometry: This bike was designed to go real fast off road.  It features aggressive yet traditional cyclocross racing geometry and goes like hell.

Tire clearance: You can fit 38’cs in this bad boy front and rear, no problem.  If you’re running fenders it’ll clear 35’s.

Steel tubing: Steel remains the preferred material for those who appreciate ride quality. It is the benchmark that all other frame materials are compared to, nothing matches its ride, fatigue life, or affordability.

Signature Dropouts: Investment cast from stainless steel, featuring built in chain tensioners, and the timeless Hennepin Bridge icon. 

Removeable brake studs:  This is a nod to our fixie riders. If you’re not using them, remove them for weight savings and cleaner lines.

Subtle fender mounts:  We hope you ride this bike in all conditions all year long, so with that in mind we added fender mounts.  Since this is a race bike and we think traditional fender eyelets on race bikes are ugly, we hid the rear ones on the inside of the seat stays, and placed the fork fender eyelets on the blade to keep it looking clean.

Build Specs

Head Tube: 1 1/8th inch

Bottom Bracket: 68mm

Rear Spacing: 130mm

Seat Post: 27.2

Brakes: Cantilever

Dropout Hardware: M4 x 0.8 x 40mm full thread

Max Chainring: 48 tooth

Part Numbers

Part Number Size Color Description  
FM4720 46cm Awesome Lime Color Nature Boy Frameset 46cm  
FM4721 49cm Awesome Lime Color Nature Boy Frameset 49cm  
FM4722 52cm Awesome Lime Color Nature Boy Frameset 52cm  
FM4723 55cm Awesome Lime Color Nature Boy Frameset 55cm  
FM4724 58cm Awesome Lime Color Nature Boy Frameset 58cm  
FM4725 61cm Awesome Lime Color Nature Boy Frameset 61cm  

Geometry

Geometry
 Size46cm49cm52cm55cm58cm61cm
(A)Head Tube Angle70.57171.57272.572.5
(B)Seat Tube Angle7473.5737372.572.5
(C)Top Tube Length520535550565585605
(D)Seat Tube Length485.6515.5545.4575.4605.3635.3
(E)Chainstay Length415420420420420420
(F)Bottom Bracket Drop707070707070
(G)Fork Offset454545454545
(H)Axle to Crown395395395395395395
(I)Head Tube Length95110130150175200
(I)Wheelbase985.7997.41003.61014.41024.21044.2