Making your Own Motorcycle Cables 1996
Some of us have experienced a pulled cable end, be it throttle, brake or clutch and our machines also have a compression release. It’s a bummer when this happens, especially at night, away from home. When building or restoring my bikes, going back to my 1st doodlebug (using electrical solder) and now my Rapides and R90/SRS, I like to make my own cables, because they fit the bike and I can place the adjuster where I want it. It is not an easy task but rewarding when done and working correctly.
There are several distributors of cables, cable housings and fittings, with Flanders and Barnett my two of choice. I buy the universal throttle cables that have a factory made ‘ball’ @ the end. The rest of it has to be fitted to your machine. I also like to bend a ¼’’ radius tube to fit right at the carb top, so that notorious kink is eliminated altogether. Mikuni makes a very good rubber dust boot to help protect all cables from dirt. I also use black heat shrink to cover these boots as time and sun deteriorates them. These will fit at the adjusters as well. You can situate your adjuster where ever it is convenient for you. I use heavier cable for the clutch and brake assemblies and make both ends to fit.
Most store bought cables are made of 1 x (17 or 19) strand inner cable with sizes from .046 to .120, fitting mopeds to big bikes. The better inner cables are made of multiple strands referred to as a 7 x 7 cable, with seven groups of seven strands in each group, a total of 49 smaller strands. These are still about the same outside diameter size, (O.D.) wire so they will fit into your machine’s outer housing, should you wish to re-fit. The best part about these inner cables is their flexibility and tendency to work easier in a tighter bend radius.
The outer housings are available in two types: lined with Teflon and unlined. The better outer cable housings are also made to be more flexible. They are made w/ more and smaller wire diameter spiral wraps for flexibility. Their size depends on the application and the inner cable sizes.
The other three parts to this work project are the outer cable end covers, inline adjusters and inner cable ends & fittings, usually made of brass. There are dozens of end fittings to anchor any number of combinations to fit levers and /or engine levers or rods. The outer cable end cover fittings are to make the housings look clean and provide proper fitting into the abutment. I like to grind the outer housing end flat after cutting it, using a sanding disc or wheel, and then insert an awl to clean up that inside spiral cable to eliminate any inside burrs before I put the outer cable end caps on. The adjusters can be put any where you like them for easy access and fine tuning. Magura makes nice rubber protectors and are great as dust covers. I also slip a piece of heat shrink over ALL dust boots to ensure sun protection. After you measure and place the inner cable be sure to ‘’flare over’’ the last 3/16 or 1/4’’ inch to help secure those ends from pull-outs. After the solder job is complete you can then grind the fitting so you have NO external wire burrs.
The one item I have not mentioned yet is probably the most important, the solder. We have all used in a pinch not knowing any better the old standby solder readily found in our garages. Electrical 60/40 Tin-Antimony-Lead solder, plumbers solder made of 50/50 silver leadless or 60/40 tin-lead solder. Silver, Zinc, Indium [a silvery malleable fusible chiefly trivalent metallic element that occurs especially in sphalerite ores and is used especially as a plating material, in alloys, and in electronics ] and Cadmium are also used in combinations in the making of various solders; each has their pluses and minuses. Most of these are flux core solders but that does not mean you can not add your usual paste-flux to this process. These types of solders have a relatively low tensile strength of 4500-6000 psi. Now just because the above plumbers silver leadless solder says silver, does not mean that it contains a good amount of silver content, maybe 6-9 % at most. Silver solder is by far the best way to join the fittings in this case, inner cables to brass fittings. There are many silver solders on the market, used for a multitude of purposes, most with heat ranges around 900-1400 F. degrees working temperatures. This depends on content and percentages of alloy material. This is too high for our use when cable making. Infact it is best NOT to use an open flame- torch on inner cables, but a very good soldering iron is needed. Some of you may have your soldering pots and used them for decades, and they work.
But silver solder does come in a lower temperature heat range for gas type torches without oxygen and iron use. I prefer this product MG120, also known as MG120A. This product‘s working temperature is 430 degrees, perfect for soldering iron use. The MG product has 3x the tensile strength as these electrical types. These MG products use a flux core and cleaning agent for the preparation of bonding. The MG120A has a syringe applicator for the cleaning agent whereas the MG120 is a bottle. It is available at welding supply stores.
The key to a strong union is wetting and capillary attraction. Wetting is the ability of the molten solder to coat the strands surface. Capillary attraction is its ability to flow or wick. I prefer to ‘’tin’’ the inner cable end after I have slid my end fitting on to the inner cable first. This allows you to ‘’work over’’ /mushroom or flair the multiple ends more easily to prevent the dreaded pull-out. Pull the inner cable back to the fitting and solder. Trim or file the fittings when done.
Remember to lubricate all your non Teflon lined cables once a year by buying one of those simple spray type lubricators available at any good local m/c shop. I use a spray can of white lithium grease. These lubricator devices clamp over the outer cable end, have a small rubber hole built in and the grease squirts inside, down the cable housing through to the end. If you use a junction box with a single throttle cable to twin cables make sure you protect that junction from dirt and debris, clean and lube with light grease once a season along with all of your other cables.
Remember what Owsley Bear says ….… ‘‘They love to get out and play in the sunshine.’’
>> made by: Messer Company - MG Welding Products N94W 1455 Garwin Mace Drive
Menomonee Falls, WI. 53051 USA (262) 255-5520 -- (262) 555-5542 fax#
Hardness 15 10 kg/ mm2 approx 15,000 psi Melting point 430 degrees F 221 degrees C
Available in :: 1/16’’, 3/32’’, 1/8’’ >>>> use 1/16’’ for cables @ most any good welding supply.
J. S. Wilson VOC ~ OS#1467, IBA, IOC, ABC, Northern California Vincent ~ H.R.D ~ Dancing Bear S.O.