purebikes 

I have been really digging the old school MTB frames lately and scored this off of CL the other day for a really great price! From what I have found it is a 1985 Diamondback Apex that is completely original, even the tires! The seatpost is fairly scratched up but otherwise it is in good shape. There are some scratches to the paint but nothing too bad. I will be building it up as a drop bar conversion with some nice parts but wanted to document the conversion from start to finish. I really like some of the details on this bike especially the chainstay protector/spoke holder. The stem is also interesting(Nitto?), it is basically a 1" threadless stem that has a quill steer tube that it clamps to. I have a nice dirt drop setup that I was going to use on it but I might try and make the original work. I have also seen these with two bottle bosses on the down tube so not sure if that denotes the year or not.

I will post more pics as I build it up and please let me know if you have any vintage Diamondback info or catalog pics.

Parts break down:

Tange butted tubing
Shimano deer head front and rear derailleur
Shimano Deore cranks with biopace rings
Shimano Deore front canti brakes
Suntour XCII pedals
Suzue Sealed hubs laced to Araya rims
Nitto? Stem and riser bars
Shimano Deore brake levers
Shimano Deore Thumb Shifters
Suntour Rollercam Rear Brake (Chainstay mounted)

clubman 

There's nothing on that bike not to like. A beauty. The hubs are really cool without the cutouts. A Japanese version of the Harden Bacon slicers of old. Nice.

Henry III

That fork is a spitting image of the Schwinn Cimarron fork low rider mounts and all. Very cool project.

The Golden Boy 

Yeah, that lugged unicrown fork is cool. I wonder if they thought the fork needed the lug or a fork crown or if it was just close to how they used to do it, or if it was a stylistic choice.

purebikes 

I really like the fork too. The lug definitely adds a nice touch. I have seem some early bmx forks that were similar so it might have been a structural concern or thought to be stronger than a weld.

KonAaron Snake 

Congrats...what a great score, and unusual in that sort of condition. LOVE the deerhead derailleurs.

frantik

Very nice. I have one of those, it's my daily rider. Here's an old pic of mine.. it's basically the same as in this pic but some parts have been upgraded since it was taken. I wish I could find a second frame in my size i would do a drop bar conversion on the second frame



There was a review in the March/April 1986 issue of Mountain Bike for the Adventure magazine (more issues here: 1986 - CB Klunkers )

btw i'm not 100% sure but I think the model year is 1986

purebikes 

Thanks Frantik! Those articles are great. It talks about the fork in the first one. Sounds like it was a structural decision.

Yours has the double water bottle bosses on the downtube correct? I wonder why some have it like that and others have the more traditional setup? Maybe it was a mid year change after some feedback?

frantik

yeah i have two bottle cages on the downtube. I think because yours is smaller they put one on the seat tube and one on the down tube

Clang

A cool bike in great shape. Congrats on the find! I have a Diamondback Ascent, also an '86. I was interested to see that yours has the same nutted axles (and lawyeriffic wheel retention tabs) that mine has. I'm looking forward to seeing more of your project.

bikemig 

Cool bike; that's quite a long wheelbase as well. Even though I have two vintage mtbs, I keep my eye out for them on CL. I'd pick up a 3d if the right bike showed up. They're fun bikes.

El Segundo

Cool bike! Looking forward to the build pictures. I have an Ascent EX that I bought new in 1988, still love to ride that bike.

The Golden Boy 

In that first article posted- it mentions the 17.5" wheelbase as "short."

Santuri32

Nice bike, I’ve had three they are very comfortable (relaxed 69 headtube angle like early Ritcheys and Stumpjumpers), about 30 ponds and full of touring bosses. Your bike is a 1986…they started making frames for that model during mid-85 to sell as an 86 model as best I have been able to gather the little information available. There should be a 5 in one of the three first serial code characters. Something like [X5] but sometimes pre-ceded by an F perhaps for a Japanese Factory. At one time during the 87 model its production changed to Taiwan.
-The Nitto MT-2 stem is reversible, still can be purchased for around $75-100. The bar should also be a Nitto B801, one of the nicest mountain riser bars, in my opinion.
-Tange Mountain Frame with earlier models came with Infinity Tubing (see Frantiks’), top tube has a nice “ping” to it, almost Tange Prestige-like. Sizes over 20” came with two bottle bosses on the downtube.
-The beautiful Suzue hubs have cartridge sealed bearings which were on the early side for production mountain bikes.
-The fork is made by Tange, this is only 2[SUP]nd[/SUP] year of uni-crowns, third if you include late 83 adaptation in some Ritchey-Fisher bikes. This was probably based on the Specialized “lost wax” (if someone can explain that term to me I will appreciated) uni-crown with the lugs. Coming from the crowned forks, the lugs probably were believed to be necessary on MTBs at the time (just guessing here).
Nutted Axles in 86 changed to QR’s in 87, also the roller-cam changed to U-brake.

frantik

hah I LOVE the ping sound my frame makes. I've wondered how the non-infinity frames feel, if any different. I wish I could find another one in my size with all of the original bits

btw, are you sure production moved to Taiwan in 87? I have an 88 Ascent EX which was made in japan, I assume the Apex would be made in japan as well. I had an 89 Apex and it was made in Taiwan

purebikes 

Thanks for all the info Santuri32. I am planning on getting into the build this weekend. I will update the thread with pics of the process. I will probably do a test ride as is to see about original ride quality.

belacqua

Lost wax (IIRC) is a casting method where you model the part in wax, pack the wax model in a heat-resistant medium like sand or ceramic, heat it, drain the melted wax, and fill the resulting void with molten metal.

Santuri32

Not an expert but maybe these were commissioned to more than one factory, my son's Tangerine 87 was made in 1986 date code starts with 6FU (no joke, late 86 build); "F" refers to Akisu Fujiyama (these have been referred as the "good" Taiwanese frames). I see nor feel any difference between my '86 Japan Made and the 87 Taiwan Made bikes. What's your frame size?

Santuri32

Never thought it referred to a casting technique, I appreciate the info.

Santuri32

My pleasure, try inverting the stem and using a flat bar...very curious to see it like that, although is referred as reversible stem, Ive never seen one like that possibly not great? Just don't run it in mud, but if you do be prepared to clean the roller-cam.

Santuri32

17.5" was on the short side for that time, one of the shortest was Stumpjumper Team at 17" regular at 18", I think chain-stay length on my 84 SM500 was also called short at 17.5". The good thing is you could fit a rolled tent behind the seat tube.

The Golden Boy 

I think both of my MTBs, an 84 Stumpjumper and 87 High Sierra had 18+ inches of chainstay. Cray Cray Chain Stay.

Santuri32

My '82 Stumpy has 18.5", I believe 82-84 were 18.8", 85-86 18", Team 85-86 were 17"

Santuri32

Then again, Surly Long Haul Truckers have 18.1" chainstays

frantik

mine is 20"