Vintage Ness Styled Springer Project - Page 1
A few weeks ago my friend Duane Lansing of Hydro-Fabrication in Wylie Texas received a request from a couple of his buddies to cut some trees on his water jet machine based upon patterns from two old fork sets they had that were sold by Arlen Ness back in the sixties and seventies.
This started out as a fairly straight forward project as we had access to the original parts, or at least we thought they were original parts when we first started the project. After doing a little research however it turns out Ness apparently had several different versions of these Springers made to his specifications. What makes the research a little difficult is that these particular forks were made before the popular appearance of 'Chopper magazines' in the late sixties so there really isn't a whole lot of published material that can be searched for photographs or old advertisements. Most of the snapshots used on these pages were just culled from Internet discussion board threads. Both the 'Jockey Journal' and 'Chop Cult' have some excellent threads running about these old forks.
As far as we can determine Ness didn't actually design the forks but instead adapted an old design that was popular in the early sixties mostly for Springer Trikes and rigid Girders.
To make matters even more complicated it seems that several companies and small independent builders sold forks having the exact same style under various 'trade-names' and these businesses had no connection to the Ness shop with the exception of Century Enterprises of San Leandro and Universal Engineering of Concord California.
I'm not to sure why people started calling this style of Springer a 'Ness Springer' except that most of the ads seen in the chopper rags from the seventies and early eighties were from the Ness shop even though other makers were selling the same forks under other names before Ness started to market them. Today I see a trend where folks are finally starting to use the term 'Century Springer' to specifically identify those forks made by that company as opposed to other similar designs.
Ness actually made a Springer of his own design that he used on his show bikes and it has very little in common with what people normally call a 'Ness Springer'. His personal design is shown in the photo below. These forks are extremely rare. I've only seen seen three sets for sale in the past ten years
Note the integral handlebars and the lack of a lower tree that wraps around the tube legs. It's hard to see in this snapshot but the upper tree is sculpted to follow the contours of the springs and the rear legs. We'll post plans for this style later on in this article.
Century Enterprises, owned by Ronnie Nunes and Jim Jennings, made a variety of both bike and car parts and made the Springers and frames that Ness sold under his trade-name. There were at least two different versions of these forks over the years and several minor differences between forks of different vintages. At some point in time Century ceased making bike parts, moving into doing more dragster work, and the fork and frame building business was taken over by Jim Davis who is famous in his own right for his dragster chassis work.
In roughly the same time period Stu Lundberg was operating a fab shop in cooperation with Ness called Universal Engineering (UE) That also made a variety of aftermarket parts including Springers that were virtually identical to those made by Century except these forks were welded together in a conventional manner, (the Century forks are of 'bolted' construction). It is not uncommon to find these old UE forks built in different widths whereas the Century forks only came in one. You can also find old UE forks that have straight front legs instead of the 'coke-bottle' curved fronts.
Ness did make one change to the forks he marketed to set them apart from others and that was to use 'counter-wound' springs. One coil was wound left-hand and the other coil was wound right-hand. If you happen across a Springer that looks like an old Century/Ness model and it doesn't have these unique springs then it's a good chance the forks were sold by another retailer. Of course people do occasionally replace the springs but this is usually the last thing done to vintage forks. If the chrome and rust on the springs is consistent with that seen on other parts of the forks then you're usually not looking at a set of forks that came from the Ness operation. Unfortunately there are some eBay and Craig's list sellers who try to pass off 'clone' forks as Ness forks since they can double the asking price.
For the sake of simplicity, from here on out, I'll just refer to the whole batch of similar forks as 'Ness style Springers'.
With respect to materials all of these forks used 5/8-inch plate for the trees, 1/4-inch plate for the spring bridge and 1-inch tubing (and solid stock) for the rear legs. The front (sprung) legs varied from 5/8-inch , 3/4-inch and 7/8-inch in diameters. Other builders who have worked with these forks have told me that some used solid bar stock for both the front and rear legs while others used tubing which they found out when they shortened some forks. Who used what and when is unknown but the tubing used was .120/.125 wall material which in my opinion is pretty thin for a Springer. Ironically I've never seen a Ness styled Springer that was anything less than 12-inches over stock though the original adds stated that forks could only be made up to 12-inches over stock.
Rockers were pretty rudimentary being made from 3/8-inch flat bar. About 95% of the rockers are 'straight' but every now and then you'll see a set of originals that have a slight 'arc' in the shape. In most cases the Ness shop reserved the 'arched' rockers for 'show' bikes. Many riders thought the original rockers were pretty ugly so it's not uncommon to find these old fork sets with a huge variety of different rocker patterns mounted.
Several different styles are used at the termination point of the fork tubes where they transition into the 'flats' where the rockers bolts are situated. There are also different terminations between those fork sets made with solid bar legs and tube legs.
The photo below shows the original type of leg termination (and a stock rocker), where the legs were made from solid bar stock the material at the sides was simply machined down on each side to create 'flats'. The bottoms of the legs were usually left 'square' and not radiused.
The legs in this picture are actually nicer that a lot I've seen since they have nice scalloped 'transitions' from flat to round. I've seen a lot of other legs, both original and later additions, that are just cut 'flat' across.
The same type of terminal is used on legs that were made from tubing except that the ends are machined 'stubs' that are welded in place and the blended in to look one-piece.
There are however other types of terminations used on the original forks like those seen here built by Jim Davis where short sections of tubing are used to form trunnions for the rocker bolts. Note that these 'improved' forks also changed over to using 5/8" shoulder bolts instead of the original 1/2" bolts that didn't hold up to well over time.
Some companies sold 'replacement' legs for these forks that used 'threaded' bungs since bent legs were not uncommon on these forks. In fact 'bent' everything was fairly common with these forks so you will seldom find a set that still has the original upper and lower trees or even the steering stem.
That isn't to say that these were 'bad' forks but just that people really put them through their paces back in the day. These were all very high quality forks even by today's standards. You have to keep in mind however that these forks were primarily intended to be used very light weight bikes that people called 'Diggers', basically a drag bike for the street. Putting an set of these original forks on today's 600 pound Big Twin Chopper might not work out to well.
I found this picture of what I'd call a typical 'Digger' on Jeff McCaans site.
Note the 7/8-inch frame rails which were typical on these light-weight, Sportster based, bikes and the Ness front-end with a 19-inch wheel.
Just as a side note, I have seen these forks with larger diameter rear legs, up to 1.25-inches, but I don't know if these were 'original' legs or modifications made by previous owners.
Basically there are two distinct 'types' of these Ness inspired forks. The earliest type is what I call the 'flat-top' version where the spring perch and the top tree are one part as shown in the picture below.
You can also see in this view the old two-part lower tree that was discontinued very early on in the development of these forks. I've seen at least five different version of lowers trees used on these forks that we'll discuss later on.
You'll find some minor variation in the shape of this top tree over time. Sometimes you see a few move 'curves' in the edges, especially in the front portion between the springs. Basically both the upper and lower trees were 'clamped' to the leg tubes via 'cinch' bolts. This is a concept used by a lot of builders over the years to save fabrication costs but it generally just doesn't work out to well in practice. It didn't work out well at all for Century who had a flood of complaints about their products. The cinch bolts on the 'flat-top' type upper was discontinued very early on and instead the rear tube leg was threaded for a conventional top bolt.
You'll also run across several different methods used to drill the holes in the top tree for attachment to the rear legs. The most common method is simply a one-inch hole in the tree, usually accompanied with a set of one-inch diameter handle bars that bolted via set screws onto the rear legs of the forks. There are also trees drilled with a 5/8-inch hole that held a 9/16" machine screw that went into the rear legs which simply butted up to the underside of the tree. Occasionally you'll see trees that were bored for the 9/16" bolts but also have a shallow 1.063-inch counter bore on the underside.
The sketch below illustrates only a few of the many variations you'll run across in the design of the old 'flat-top' type upper trees from various makers. Some have zero stem offset while others have one-inch. You'll see some with 'piercing' every now and then. You'll also see variations that have no holes drilled for conventional handlebar mounts.
Several other companies during the early seventies tried to build and market so-called 'bolt-together' Springer forks but none of these endeavors was successful over the long run. What was happening with these early forks was leg flex and steering movement was 'opening' up the outer edges of the 'joints' between the clamped parts and the thru-holes were becoming elongated leading to a generally sloppy fit between parts. Compounding the problem was the fact that the steering stem was actually threaded into the lower tree. Several attempts were made to solve the problem by re-designing the lower tree, at least three times, before this design was finally completely abandoned by all manufacturers.
There are still some folks out there who like this old original style of fork construction and there is nothing wrong with it as long as you occasionally replace the lower (and/or upper) tree so that everything stays nice and tight.
The sketch below represents some of the styles various makers used on the lower tree over the years. I've seen several others but these five are very common. The original two-part lower is shown on top.
I found this snapshot on the web and while the quality isn't perfect you can see, if you look closely, that the end of the lower split-tree is beginning to open slightly and that the 'plane' of the rear legs in relation to one another and in relation to the front legs is slightly off even taking in account camera distortion. This is typical of cinch-bolted construction used on forks.
The second generation of Ness/Century Springers went back to a more tradition style and utilized a conventional spring-perch with a separate top tree. as seen below (minus the top tree). This 'second-generation' of forks are perhaps the best of the Century/Ness production forks as there are still a lot of these around and most found at swap meets are still in excellent condition.
They also went back to using conventional welding of the fork tubes to the lower tree and spring perch since the cinch bolts used earlier didn't work out all that well in the field. You will still find some early versions of this fork that still utilized the 'bolted' lower tree but they are pretty rare. The shop had a lot of the old two-part lowers in inventory so they were just slightly reworked into becoming the new upper trees for some of these forks as seen below.
You'll also see variations in the Spring Bridge used on various forks. Some of these examples are shown in the sketch below. Most of these forks were originally designed so that the headlight was mounted to the bridge but a lot of riders found the 'light bounce' at night to be annoying so it's not uncommon to see the upper tree drilled for mounts on modified forks.
Regardless of the specific style or configuration these are very simple and relatively economical forks to build, especially the old 'flat-top' type so they are becoming more and more popular for small independent shops and backyard builders today. Most folks however won't bother to use the 'cinch-bolts or bottom threaded stems and will opt instead for welded construction and stronger tubes.
I'm seeing more and more repops of these forks being built with 1.125-inch rear and .875-inch front tubes and even some that are built slightly wider to accommodate a single disc brake.
On this particular build we'll stay with the original dimensions and specifications. I'll skip over some of the rudimentary stuff since we covered a lot of basic fork fabrication techniques in the Old School Springer Build article so it might be a good idea to read that material first.
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