Here are some general non categorized observations, primarily regarding operation.
- Starting: You have a couple of vulnerabilities here for which you are advised to work around. The kick start mechanism, though robust is not intended to be used habitually without employing the decompressor lever. To a lesser degree, decompressor cable and mechanism life can be extended exponentially if you use the engine to raise the exhaust valves off their seats for a static hold with the lever rather than asking it to do the same by squeezing it (very) firmly.
Any properly tuned Vincent in essentially stock (original carbs/Lucas magneto) will start predictably in the same manner. When cold, tickle the carbs till evidence of gas is just seen at the small ports on the carb bodies just above the large gland nut securing the jet blocks to which the float bowl arms are attached. Depending on ambient temp, 1 -2 slow complete slow follow throughs with the kicker arm on a pulled decompression lever. No need to employ the dual choke levers. Then, ease the kicker slowly down till the first evidence of compression felt, ease the kicker slightly to let the lifters raise the exhaust valves off their seats, hold this static position with the decomp
lever, provide a sharp kick releasing the compression lever at approximate 7 o
clock viewed from the right side while just feeding in the slightest amount of
throttle to catch the motor as it starts whle keeping the rev's low. Always advisable to remove your oil cap and confirm returning oil to the tank indicating lubrication to your upper valve train. A warm machine will start readily with no priming kicks: ease the lever down till compression felt, then hold the decompressor lever on valve raised off the engine's lifters, and the kick as outlined earlier. Correspondingly, it's advisable to fit a kill button (same as horn button and available from John Healey)to ground the magneto rather than using the decompressor lever to stop the engine.
If you need the stability imparted by having the machine off the ground, acquire a Hill's type or Vincent D center stand, do not start it on your rear stand, it will lever the RFM bottom axle adjuster slot downward (#1) spreading the slot open.
- Performance: Unlike most vintage American machinery of this era, because a Vincent’s engine performance envelope is more precisely defined and limit more discernible and readily reached, it is more sensitive to elevation changes where jetting is concerned. Generally jetted rich to begin with, leanness is not usually a problem with original carbs, overly rich conditions and plug fouling on Lucas magneto equipped machines can be a potential problem. I have only ridden the Red Rapide at higher elevation (10,000ft) and with needle positions the same, air screws out 1/8 of a turn, main jets were dropped from 195/185 to 175/165 respectively to maintain the same performance feel at sea level, acknowledging that less total performance available due to less air density, but pleasant for two up riding. The Shadow on stock carbs, needles middle and pilot screws at 1 1/4 is now able to run with both main jets the same by virtue of a BT-H and these mains are the originally specified 185's.
- Plug Fouling: Without the luxury of point/coil battery ignition to provide a healthy spark at lower rpm where this configuration excels over a magneto, Be sure to familiarize yourself with jetting - which varies between front and rear cylinder on Lucas KVF fitted machines - and pack the appropriate ones if you’re journey will include significant elevation changes. Plug fouling is essentially the spark finding a path via carbon buildup from the electrode to the insulator and then plug body and ground for current flow by-passing the ground electrode. Easy to remove with a brass brush, brake clean and a flame when new, plugs become less responsive to this technique as the miles accumulate and carbon is pounded by the combustion process into small spaces where it cannot be removed readily when by the side of the road. Unlike battery ignitions which can blast through resistance, by comparison, with fine windings, magnetos require a ready path to ground to prevent damage and have ground poles to which the spark will shunt if any measureable resistance at the plug is detected and thus cannot be relied upon to do the old hold-the-plug-cap-off-the-plug trick to clear off fouling through resistance building further coil saturation for additional spark energy like battery ignitions will do regularly.
Plug fouling due to oiling from worn valve guides or rings must be addressed quickly as stock magnetos have little/no reserve to burning this off and your front cylinder - only benefitting from 50 degrees of crank rotation before the plug fires - will be the one that causes you the most problems in this situation.
02/09 Update: BTH Magnetos: Fitting a BT-H will nearly eliminates any propensity to foul plugs under way and even heavy handed carb tickling has yet to cause any concern when starting.
- Sprockets/Chains: The factory build sheets on file at the VOC for your machine state what final drive sprocket was fitted when it left the factory. Customarily this was a 46 tooth which for lighter riders on relatively flat terrain not operating a machine with the tall 7:1 bottom gear (standard on mid 1950 and earlier Shadows) or having the larger diameter 19 inch rear wheel and is entirely satisfactory. Vincents by design are extremely over geared, many fit a 48 for brisker response but both my machines are fitted with 46's including the Shadow having not only the higher bottom gear but 19 inch rear wheel as well. If you change your sprocket and particularly if this is installed on the more brittle cast iron Shadow drums (ribbed, 10 lugs on the rear) if is important you retighten the retaining bolts after bedding in or risk breaking the drum mounting flange if the sprockets comes loose and shifts.
With a good ESA, Vincents are very good on chains as they maintain good/uniform geometry through rear suspension travel which reduces typical tendency to have the chain tighten and stretch as the suspension compresses. Though o-ring chains available to clear the very tight confines of the front sprocket area, a standard chain is adequate can last thousands of miles if maintained, but should be changed if adjustment exceeds a 1/2 or so from new as a thrown one can wad up and damage the engine cases. Do not over tighten your chain, it will stress the drive side wheel bearing race in your rear hub ruining its interference fit and causing it to loosen and shift.
- De-Compressor Setup: The most ready source for oil leaks from your Vincent occur at the port in your timing cover where the pin (MO13 - ET165AS) emerges
from and the nests within the ET168 capped by the ET172/2. The spring (MO18 - ET129) is entirely to small to draw the pin against the two sealing washers and in some cases not even adequate to draw the slack out of the release wire. Needless to say, if you adjust your decomp handle like your clutch to where there's very little slack on pull till resistance felt as the cam followers are raised against valve spring pressure then in all likelihood in a resting or standby position, your pin is not even resting against the sealing washers and thus your timing chest basically open to atmosphere. Oil exiting here in any quantity coats the right side of your tire and you run the risk of it covering the tread face - not good.
Slacken the cable adjustment, removing the ET168 and ET172. Check that your pin is tensioned against the two rubber washers (recommend replacing them), if not add a third, then with the sparkplugs removed, slowly turn your engine over to ensure your ET69R's are not being struck by the lifters, you may want to feel for any gap by turning the motor over again while pulling the pin outward further to feel for the first hint of its pulse in your hand indicating lifter contact, this will establish your resting/standby clearance. If your spring feels weak then in it will likely not have enough strength to pull the slack out of your wire, return your handle to is resting position without leaving the pin boss off of the rubber washers. Trim about a third of a length of a spare carb spring (or suitable Lowe's sourced substitute) and work it onto your decomp cable at the engine end. With your cable end inserted in the ET165AS head, this spring uses the ET172 as a backstop to pull all cable slack out and ensure your handle returned to its stop.
To adjust. You need only pull the valves slightly off their seats to bleed off compression sufficiently to kick the motor through with little resistance. Thus, with the ET172/2 on the cable, inserted through the sleeve, affix the cable end to the pin boss and adjust the cable till the ET172 is just about drawn against the sleeve insert your cable end into the pin head
- Cables: arrive raw, uncut and you'll need to measure, cut and solder up the ends. As inner cables may be of either steel or stainless steel it is important to determine which as this will dictate the flux and solder used to ensure a good bond. Silver solder is preferred and I will defer to Jim Wilson's excellent explanation here, scan down to Soldering Cables on the page.
- Paint: Original - Older Repaint/Roadworthy As full restorations follow essentially the same template, this section assumes a basket/non runner/runner for which you want to preserve/create some semblance of originality, thus covers either saving your existing paint or a reasonably expeditious alternative to the debatable skill of antiquing repairs to match patena. Originally black Vincent cycle parts were dipped and the Black Shadow motors stove enameled, thus their finishes were never flawless but the stove enameled parts have proven incredibly durable while the cycle parts have generally deteriorated to a semi flat finish.
Fuel tank. If yours is original or wears a re-paint at least 40 years old it may likely have original or more accurately colored decals, possibly gold leaf or at least a quality striping job if redone by Conways or similar. No matter how dingy, it can be revived and this finish is not only worth preserving but now must be protected from our noxious fuel formulations
for which no non catalyzed vintage clear coat is adequate. But first, you must determine if it has been clear coated, either all over or just on the striping and decals. Carefully clean the entire tank with a finish degreaser available at professional Automotive paint supply stores designed to eliminate fish eyes. Using 3M 600 grit pre soaked in water to soften the backing paper to make it more compliant, carefully rub an inconspicuous area down near the front mounting tabs, if cleared, the residue left behind on your paper will be chalky white/yellow and if not, it'll be the black of your color coat. If not cleared it is time to prep it for clear coat. As this is cured paint, the objective is a good mechanical bond over the chemical bond that would possible if it was freshly applied color coat. Wet sand the entire tank with 1500 grit a section at a time, intermittently go behind your work with a rubber squeegee of sponge drawn across the surface. The objective is to have it all a matt finish, any low spots/damage not addressed will manifest itself as shiny spots. This assumes the objective of getting this surface as perfect as possible, leave imperfections behind to the level of patena you desire. Being a liquid and subject to surface tension, improperly applied clear coats to do not cover any surface elevation changes like decals or striping predictably and there may be thin sections, thus, you cannot be too careful with these, merely scuff them enough to knock any gloss off. Wash sanding residue off with water and then wipe completed tank with degreaser.
If your tank has been completely clear coated then carefully wet sand with 600 grit checking your residue as you go, the first hint of black, stop. Many factors influence final paint surface depth so you will need to check residue constantly. Merely scuff the decals/striping with 1500 as above. Be advised, any remaining aged clear coat left behind will appear as cloudy spots in the finished work once newly cleared, but, this is the better side of compromise compared to cutting through the black. If you have significant chips or missing color coat (often around the fuel cap boss or down near the taps), you can merely touch it up with a brush and cut it back with 600 level with the surrounding area.
Vincent fuel caps have a very thin cork gasket and are prone to leak when full and left on the side stand. Often not only the paint is damaged but the right side Vincent decal may be partially lifted from the surface around its perimeter and must be reattached. Feed very small amounts of water soluble Elmer's Glue under the edges and squeegee flat with a moist cloth. I have also re-adhered decals by mixing small amounts of clear and hardener. When complete prep as outlined above for paint.
Clear coat. Two schools of thought on this one. In addition to scratching and pitting, exposure to sunlight yellows vintage clear coat all the way through like vinyl rear windows on old convertibles. Some patena restorers elect to mix de-glossing agents in with their clears but this not only adds an opacity that distorts the underlying decals/striping's appearance, it is too uniform and does not mimmic real world wear patterns/sun exposure effect. I shoot mine unaltered and then vary the surface with wet sanding and buffing, if desired.
The following applies using Glasurit MS Clear shot through a gravity feed Sataminjet similar to this one at 28PSI. Aged paint, even lacquer should not pose a rejection problem but it would be wise to shoot a small area on the underside of the tank just to make sure. If you do not paint regularly it is advisable to make a piece as unwieldy as a fuel tank readily rotatable to permit flowing out any runs, here's my solution but at a minimum, make up handles for front/rear tank brackets. Though dry/semi dry coats provide a good tack base and can reduce propensity for runs, but if allowed to flash off, they will show in clears as cloudy areas, thus try to shoot two or three wet coats with a bit longer flash off time between each. As you'll be wanting to flatten the upraised areas comprising the decals and striping, spot paint those with generous margin with a few extra wet coats, don't worry about blend lines to the rest of the tank, you'll be cutting that back with wet sanding. To replicate a well used but still pleasant appearing original/older repaint, following a 48-72 hour flash off and partial cure, wet sand with 1500 backed by a 2 x 4 inch rubber square available at auto paint suppliers. Periodically squeegee off your work to check for achieving a uniform matt finish. If going for exceptional gloss, back this up with 2000 grit, otherwise progress to buffing.
The objective here is to achieve a gloss but with a halo of fine scratches to duplicate wear. Using 3M Finesse-it II on a dimpled foam pad at 1,500rpm, make a slow wet pass, then back over the same area till dry. As this paint is not fully cured 72 hours out, do not linger to the point where you feel noticeable heat, you will stretch and break the structural integrity of the paint. Wipe off with a towel and inspect. Repeat buff till desired gloss is achieved. More original appearance can be achieved by not buffing the area around your fuel filler neck to a gloss, more glossy sheen over the top center of the tank where wear is minimal and more scratches left on either side at the rear of the tank where pants legs contact it.
Pictured is a before and after of my Black Shadow fuel tank. It sat in basement occupied by many cats have full of fuel for 31 years. Moisture (cat sourced or elsewhere) completely etch the clear off the top of the tank and clouded it all over. It was missing a 3 inch diameter section of paint down to the metal around the side over left fuel tap and the left side Vincent decal was lifted about a 1/16 to 1/8 inch in around its perimeter from fuel leaks. Initially, to adhere to the theme of repainting this machine entirely with aerosols, I prep'd it as outlined here and shot it with artist's matt clear aerosol, which with the first splash of fuel, the surface then began to deteriorate more in a month than it had in more than the 3 decades it spent as a basket case, most impacted was the same left side decal now full raised and shriveled. With heat and applications of clear, it was flattened, reattached. After another wet sanding the aerosol clear was removed, the tank shot with Glasurit and finished to the stage you see here.
Cycle parts. I originally set out to get a dusty original Shadow to mechanically freshen while leaving the aesthetics alone, but circumstances (very low mileage, matching numbers, history and close to home) led to a (pile of) a machine much farther down the appearance ladder but the objective was still the same, a dusty trail horse for which there would be no worry associated with routine wear or the occasional scratch. Though all 60 plus pieces were hand stripped, repaired and prep'd as though to be painted with polyurethane, instead the entire machine with the exception of the stove enameled engine was shot with Rustoleum Gloss Black out of aerosol cans over bare metal. I took this opportunity to experiment with finish variation. Aerosols have none of the high solids characteristics of 2 part paints instead, primarily solvents to ensure reasonable flow out and gloss over a wide variety of application environments and techniques. Forced drying will not only flash off the solvents but can step down the gloss. Using roughly 160 degree F as a baseline, dry times from 15 onward to 20 minutes will progressively knock down gloss and give the appearance of higher surface pigment density, you'll need to experiment.
Carbs. Bodies and float bowls were painted a machine tool like silver originally (except front carb body on Shadows) but this coating rarely survives and on an unrestored machine, I'd be inclined to leave them bare. But if you elect to paint yours, current fuel formulations prevent using anything but the best cured polyurethane enamels otherwise the paint will quickly peel back at the top of the float bowl where it joins the ungasketed lid. Observed on an NOS float bowl, the pigment composition of the original coating was not bright and the metallic content very fine. A close match is Glasurit base silver stock used for adding tints to achieve color variations.
- Paint - Replicating original: Black Vincent cycle parts were originally dipped and then baked (some debate on whether Red Rapides were sprayed all over). Older paints have a higher degree of opacity then modern catalyzed paints and also benefit from not having the pigment diluted by hardener. Two replicate these finishes to any degree you'll need to select a supplier offering high-solids paints like the aforementioned Glasurit. To ensure as much opacity as possible, I shot the cycle parts using less hardener one level up on the shop temperature and used a little more reducer to aid flow out. The latter would flash off during drying. Red Rapides were painted in three batches of which my 7,200 mile machine had quite a bit of well preserved original paint. As Red Vincents tended to turn pinkish as they faded when exposed to sunlight, I used the backside of one of the front brake plates to get a computer match. This paint is Glasurit color code 027, identical to pre-1989 Porsche Guards Red.
If shooting black cycle parts, and desiring the original luster you'll need to experiment with a deglosser as these did not even have the sheen of modern single stage much less clear coated finishes.
- Seat: Original seats have rather thin bases and are prone to bow under load. Heavier riders or riders with passengers compress the suspension which in turn raises the rear of the seat relative to the nose pitching both forward every time the brake is applied. When building a seat, I use treated 3/4 marine plywood and for the Shadow which does not retain the original Dunlo Pillow foam, contoured the foam such that the nose is slightly elevated and the section where one's backside resides is now lowered. Though some original seat bases left in natural wood, I paint mine and all internal hardware as the foams act to collect moisture.
Seat covers can be head anywhere from $50 to several hundred when in leather and 8 panel. John Healey sells a very nice 8 panel reasonably priced. To fit, do a preliminary mock up to ensure top perimeter of the foam follows the perimeter seam of the cover. If the foam is obviously oversized - problem usually manifests itself in the rear at each corner, cut back the foam with 60-80 grit sandpaper. For final fitment, coat only the top of the seat foam with adhesive, not the sides, heat the cover and work it around till it is centralized and secured. JH's cover material though robust is compliant enough to be stretched or drawn together where required without visual deformity. On an 8 panel the two challenging areas are affixing the nose to the base without wrinkling in the front face and securing the sides to the base in the inside curve of the pinched area right behind the rider's seat. Attach the nose, these two sides at that location and each rear corner first. Then stretch/draw together the sides in between these points to achieve wrinkle/wave free attachment.
To avoid any surprises on the road, you want to employ the strongest spring clip to retain your tool tray and make sure the tab fully nests in the recess in the tool box face or the tool tray will slowly work its way outward and fall off.