Rickenbacker 4001/4003 bass neck – high action, bowed neck, neck pull, neck to body relationship. I’ve received several inquires regarding Rickenbacker 4001/4003 necks and bridges. Folks have seen some of my Rics posted here and asked for my thoughts concerning high action and bowed necks, and also, if I could help them understand some of the difficulties they’ve experienced with their own 4001/4003 basses. Regarding neck adjustment, please follow the instructions in/on the Rickenbacker manual/web-site. The diagrams I put together (below) illustrate the dynamics regarding the neck’s relationship to the instrument’s body. Please note that some conditions, such as ‘neck forward pull’ and ‘bow’ are exaggerated to illustrate what’s occurring. Figure 3 shows a Rickenbacker 4003 neck under string tension, with maxed-out truss rods. and fatigued wood, or timber that lacks adequate strength. Under this scenario, the neck will exhibit excessive bow, will be pulled forward (up), and will not be parallel to the body. What happens is: (1) String height (action) will be abnormally high, (2) Strings may contact pickup cover (interference), and (3) Instrument may not be playable. The Rickenbacker 4003 neck-through construction is something of a delicate matter. The neck has a HIGH DEGREE of FLEXABILITY at the point where the body wigs are attached. There isn’t much mass (wood) and also, a substantial amount of wood has been removed to accommodate the neck pick-up. Lack of wood contributes to its weakness/instability. The routed-out section on the 4003 is farther away from the base of the neck than it is on the C64 & V63. Because of this situation, there’s a very delicate balance between fit, form, and function. This inherent weakness, nonetheless, allows a person to manipulate the neck when adjusting the truss rods (flexing the neck by pulling it back to relive the truss rods’ tension). This is especially important when the rods are being tightened. There have been cases where the fingerboard has separated from the maple neck or has even popped off the neck. From a functional perspective (4001/4003 design), the instrument requires enough string tension to pull the neck forward (up) so it can be played, but not so much that the neck bows beyond the truss rods’ capacity to maintain a flat playing surface. Reference Figure 2. This is where the delicate balance becomes strained, or becomes an issue which leads to suboptimal performance. Over time the truss rods reach their adjustment capacity (they max out). When this happens, the neck will bow, and eventually, reaches a point where the action becomes incredibly high. Reference Figure 3. A person then needs to exert enormous downward pressure on the string to make contact with the fret, which makes the instrument extremely difficult to play, or in some cases isn’t playable. Another anomaly is neck twisting. There are cases when the truss rods will not correct this problem. Twisting seems to be more prevalent on necks fashioned from a single piece of timber. Over the years Rickenbacker has tried several configurations to correct this. A two-piece laminate is the current configuration (since early 2009). Some years back they employed a three-piece configuration (referred to many as the skunk-stripe). Another liming factor (regarding reducing high action) has to do with the bridge. It can only be adjusted down so far. Even if the saddles are filed, which allows the string to drop down some, there comes a point where it will not make a difference. This is especially true when the neck is pulled too far forward. When the neck is pulled beyond a certain point, not only does the action become incredibly high, the stings will come in contact with the decorative bridge pick-up cover (single chrome-plated plastic on the 4003; dual chrome-plated metal bars (horse shoes) on the V63 & C64, which are functional, so I’m told). When the neck is pulled too far, the strings move up and make contact with the cover. This is why some folks remove the covers, it’s because of interference. This is also the reason, I believe, Rickenbacker revised the configuration of the two chrome-plated metal bars. Later model C64s have horse shoes bent (formed) out, away from the strings, which provide more area between the strings and the horse shoes, which reduce the string to cover interference. Regarding low volume output of the toaster-top pick-ups. The adjustment of all toaster-top neck pick-ups is very limited. It can only be adjusted up so high. When the condition arises as shown in Figure 3, this problem is severely exasperated, as the strings move farther away from the pick-up. This accounts for some of the volume loss. The other factor might simply be a weak pick-up. Weak toaster pick-ups are not uncommon. That’s one of the reasons Rickenbacker went to a high-gain pick-up. Regarding the bridge, all of mine, and every bass I’ve seen with this bridge, are bent to some degree (tail lift as some call it). The worst is the C64. The amount of lift depends on whether the bridge is held down by three screws (older models and C64), five screws (current production 4003), or seven screws (from 1980s or thereabouts; and the five and eight-string models). Every C64 I’ve seen/and played has, what I’d call, a severely bent bridge. Drilling additional holes and putting more screws will help limit the bend, although, it does detract from the bridge’s aesthetics. The problem (bending bridge) is that the strings do not angle down enough from their anchor point; it’s shallow, which means there’s not enough downward force (tension) on the saddles. When the bridge bends too far (up), there isn’t any downward force, which makes the instrument unplayable. Bridges from the 60s were made of different metal, as well as process, which is why they didn’t bend. Metal composition and thin construction makes the current bridge (post 1960s) susceptible to bending. Hope this helps explain things. No magic, just plan old geometry & physics. I believe Rickenbacker understands these problems exist. Over the years they have made several attempts to correct these problems (inherent design flaws). For example, issuing high-gain pickups, experimenting with various neck configurations (single-piece, two and three-piece laminates), putting additional screws in the bridge to secure it from bending (went from the original 3 located under the saddles, to seven, then to five probably because the seven were perceived as an eye-sore).