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Well now! I’ve got to tell you right off the top it’s been quite awhile since I’ve had a crack at a survivor like this. I feel real good every time I look at it. I can’t help but think that I most likely saved it from a fate worse than death. The simple fact it could have wound up in the wrong hands and “parted out” was a huge driving force. This bike needed to be preserved plain and simple. So put this one in the win column kids. My job now is to see what the timeline is on these frames is along with variations and transitions in design and marketing. ABS introduced its Ashtabula line of BMX parts very early in 1975. When first launched it was a full line of accessories to modify and upgrade the Schwinn stingray and its many imitators for the dirt. It included not only the familiar forks cranks and stems but also handlebars kickstands fenders pedals and wheel sets. ABS industries spread the manufacturing out among its subsidiaries. Cecor inc. in Butler Indiana made the pedals and the kickstands. Elrae pressed metals in Buffalo New York made the steel fenders. Ashtabula forge in Ashtabula Ohio made the forks cranks and stems. Sun cycle in Bradenton Florida provided the handlebars and wheel sets. By midyear of 1975 they were advertising development of a frame as well. Word of the frame first appeared around April ‘75 in Bicycle motocross news and bicycle industry trade papers of the time. This first example of the frame produced by ABS subsidiary Sun Cycle looked a little lacking in engineering and design but from day one the ABS frame was dubbed the Black Diamond. It must not have made production because an example of the frame has yet to surface and no pictures of a completed bike have yet to be found in any historical record. Only pictures of the frame itself. Note the lack of gussets in the frames first ad. But there still may yet be hope. One frame it seems was given away to the winner of a BMX race sponsored by Sun Cycle / ABS held in Florida around this same time. This was Sun Cycle’s first attempt at a BMX frame. Much like LRV the meat and potatoes of Sun Cycle had been adult size basket tricycles for seniors. Within two months the design of the frame was completely changed. I refer to this miss step frame as the first generation. The July ’75 issue of Bicycle Motocross news contained a new product blurb about the next Black Diamond frame. Interestingly enough just one month earlier in the June issue a Bike Brokers inc. advertisement featured the same Black Diamond frame with a picture of a complete bike. The bike in that ad looks to be set up with the Ashtabula line of parts. Take away the front fender from the bike in the ad and that is essentially what my bike looks like. I refer to this frame style as the second generation frame. I’ll also take a stab and say it’s the first Sun Cycle / ABS BMX frame to make production. Going by what information I have been able to gather this version of the Black Diamond frame was produced from mid 1975 well into of Sun Cycle’s 1976 production year. The frame was set for yet another redesign before the year 1976 was out. That design being the one most familiar to collectors. With its added gusset where the top tube meets the seat tube. Along with the completely revamped front gusset. I refer to it as the third generation frame. *Warning the following is only theory and is the sole opinion of Sodbuster Labs.* In researching these frames and looking into how serial numbers run I have read about them having date codes located on the outside of the left dropout. [Date coding? What a totally Ashtabula thing to do!] I have also seen a picture of the same as example. My black Diamond frame does not have this date coding on the dropout. Instead there is a four digit serial number stamped into the underside of the bottom bracket. It could potentially be interpreted a couple of ways. First it could just fall in its place in the number sequence. Or second; the first digit is the month the second digit is the last number for the production year. Third fourth and so on represents number in production for the month. So my frame it either (as example only not real numbers) # 2685 being the two thousand six hundred and eighty fifth one produced. Or the eighty fifth frame produced in February of 1976. *This concludes the blatant theory portion of our program.* This makes nailing it down this way tricky. So I also looked to the Ashtabula forged parts that are stock to the bike to give me further clues. Going into this here is what I already knew. I knew I could date the forged parts and I knew the “Ashtabula stamped” versions of these parts were introduced for 1976. The cranks and “goose neck” stem are the stamped versions. The date codes on both of these parts indicated they were manufactured in the first two months of 1976. The fork on the other hand is not stamped and has the Ashtabula logo stickers on the fork blades. The fork has no date code stamping on the inside of one of the fork blades. It is not out of the ordinary for this style of date coding to be absent from early production year forks as the complete date code was stamped in later and not during the forging process The fork does have the year code embossed in the forging process on the inside of one of the blades near the drop out. It clearly reads '76. So this brings me to the conclusion that my Sun Cycle / ABS Black Diamond is an early 1976 production model. It also means that going by the real four digit serial number that neither aspect of my earlier blatant theory can be proved or disproved and is still at impasse. Variations: In my research on this series of frames I tried to keep my eyes open for variations or additions to the design. I did find one variation of the second generation frame in the historical record. But the information indicates this 2nd gen variation was not sold as a Sun Cycle or an Ashtabula frame. The variation is the addition of a gusset inside the front triangle where the top tube meets the seat tube. The frame is shown built and being sold as a complete bike. The new product blurb in the January 1977 issue of Bicycle motocross news shows “The Shadow professional MX bicycle.” From Shadow distributing of Xenia Ohio. With no further adue; 1976 Sun Cycle / ABS Black Diamond. Frame: Sun Cycle /ABS Black Diamond. Fork: Ashtabula BMX. Heat treated Head set: Wald. Stem: Ashtabula BMX. Stamped heat treated. Bars: Sun Cycle BMX. Grips: 7/8 maker unknown. Seat post: Sun Cycle. Seat post clamp: Sun Cycle. Seat: Messinger diamond pleated BMX. Cranks: Ashtabula BMX. Stamped 7 ½ inch heat treated. Sprocket: ABS. Mag style. Bottom bracket set. Wald. Pedals: Union rat trap. Rims: Femco, steel and chrome. Hubs: Shimano MX front. Shimano “Coaster Brake” branded rear, In black. Spokes: steel .105 gauge. Tires: Nankang B-028-33 20x2.125.