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SECTION K:

STEERING/SUSPENSION:

--Front Suspension: Fork Oil and Tools.


FORK OIL:

Unlike motor oil or gear oil, fork oil's major purpose is not lubrication.....rather, it acts as part of the suspension system, providing both damping and rebound control functions. The different "weight" or viscosity of fork oils allows you to modify the ride and handling characteristics of your bike in a fairly simple way.

And yes, it IS a lubricant also!

Although many people----including, unbelievably, Yamaha itself----recommends the use of engine motor oil as a substitute for fork oil, this is not a very good idea. Engine oils (or any multi-viscosity oil) uses additives and detergents that, while wonderful in for their intended purposes inside an engine block, tranny case, or rear drive unit, are not such a good idea inside forks. Forks operate at a much lower temperature and temperature RANGE than engine and drivetrains do, and thus do not need all those additives. And fork oil also tends to contain higher percentages of molybdenum disulfide and anti-foaming agents than engine or gear oil, both of which are very important to proper fork operation.

As a small example.......most motor oils are of a multi-viscosity nature (such as 10W30) which change their viscosity in relation to their temperature (thin when cool, thicker as they warm). A very necessary and useful feature for an engine, where you do not want your oil thinning out as the engine warms up. Not such a good idea for your suspension----unless for some reason you WANT your handling characteristics to change (get stiffer) as the forks heat up!


Proper fork oil levels and scheduled change intervals are important for fork performance and fork part longevity.....water contamination, as well as particulate wear will accumulate in fork oil, and since there is no oil filtering mechanism within your forks, the only way to get the grit and gunk out (before it chews up your oil seals and slider bearings!) is to change your fork fluid regularly. Yamaha recommends a fork fluid change every 10,000 miles or 24 months (all models except XJ700's), or every 16,000 miles or 24 months (all XJ700 and XJ750-X models). If you just bought a used bike, we recommend you do a fluid change as soon as possible, because just like other routine maintenance tasks (besides engine oil changes), this is one that has very likely been ignored for the last 10-12 years!

HINT: there's a puddle of fluid under your wheel, in the area of the brake caliper. Unless the source of the leak is fully obvious, how can you tell if it's brake fluid of fork oil? Try to mix a few drops of water into the fluid; fork oil (or engine/gear oil) won't mix and the water will "ball up"; brake fluid will integrate with water and absorb the water.


Fork oil capacities and recommended weights are as follows. The amounts listed are per fork tube:


XJ550 Maxim: 272cc or 9.20 fluid ounces. 10W fork oil.

XJ550 Seca: 230cc or 7.78 fluid ounces. 10W fork oil.

1980-81 XJ650 Maxim and Midnight Maxim: 262cc or 8.86 fluid ounces. 10W fork oil.

1982-84 XJ650 Maxim: 278cc or 9.40 fluid ounces. 10W fork oil.

1982 XJ650RJ Seca: 236cc or 7.98 fluid ounces. 10W fork oil. Fork oil level is specified as 400mm (15.75") below the top of the tube without the spring installed, forks fully collapsed.

1982 XJ650LJ Turbo: 238cc or 8.04 fluid ounces. 10W fork oil. Fork oil level is specified as 180mm (7.09") below the top of the tube without the spring installed, forks fully collapsed.

1983 XJ650LK Turbo: unknown.

1985-86 XJ700 non-X: 383cc or 12.96 fluid ounces. 10W fork oil.

1985-86 XJ700-X: 389cc or 13.16 fluid ounces. 10W fork oil.

1982 XJ750 Maxim: 257cc or 8.69 fluid ounces. 10W fork oil.

1983 XJ750 Maxim and Midnight Maxim: 257cc or 8.69 fluid ounces. 10W fork oil. NOTE: owner's manual states that the fork oil capacity is 278cc (9.40 fluid ounces). It is unknown which measurement is correct.

1981-83 XJ750 Seca: 309cc or 10.45 fluid ounces. 20W fork oil.

1983 XJ750 E-II Seca or 1984 XJ750RL Seca: 286cc or 9.67 fluid ounces. 5W fork oil. Fork oil level is specified as 168mm (6.61") below the top of the tube without the spring installed, forks fully collapsed.

1983 XJ900RK Seca: 286cc or 9.67 fluid ounces. 5W fork oil. Fork oil level is specified as 164mm (6.46") below the top of the tube without the spring installed, forks fully collapsed.

1982-84 XJ1100 Maxim and Midnight Maxim: 210cc or 7.10 fluid ounces. 10W fork oil. Fork oil level is specified as 210mm (8.27") below the top of the tube without the spring installed, forks fully collapsed.


IMPORTANT NOTE: the above fork oil VOLUMES are for use only when using the stock fork springs. The use of aftermarket performance front fork coil springs will change those volumes, since aftermarket springs are thicker than stock----and thus displace more oil. Using the stock oil fluid VOLUME with aftermarket fork springs is a sure way to OVERFILL your forks, with the very real possibility of blowing out fork seals.


Unlike with your engine oil, where a bit too much or too little oil volume in the crankcase is not really a significant concern, with fork oil, too much or too little can cause real problems (too much oil can result in blown oil seals and a stiff, harsh ride, while too little oil volume results in excessive foaming, a soft mushy ride with possible bottoming, and erratic fork performance and lots of front end "dive" upon braking).

A better way to determine the amount of fork oil that is needed and necessary is via the measurement of the fork oil LEVEL within the tubes.....sort of like measuring the oil level with a dipstick. Yamaha does not specify this level for all models; and in any case, if using aftermarket springs, the factory oil level recommendation is not always useful. The maximum oil level should be 5-1/2" (140mm) below the top of the inner fork tube, measured with all internal fork tube components installed EXCEPT FOR THE SPRINGS, and with the inner fork tube fully collapsed into the lower (outer) tube.

In order to be as accurate as possible, we recommend the use of a suitable measuring device, such as the HCP1728 oil level syringe listed further below.

And finally, the fork oil viscosity can be changed from the factory recommendations to give a softer or firmer ride.......the lower the viscosity, the thinner the oil, and the softer the ride (i.e. 5W oil is thinner than 10W which is thinner than 20W, etc.) In this regard, you would certainly be correct in thinking of fork oil as a suspension "tuning tool"! Note that a thicker oil viscosity will have much more effect on the fork "rebound" characteristics than it will on the fork compression dampening function.

A great primer on "tuning" your forks via adjusting the oil levels can be seen at:

http://www.thumpertalk.com/forum/archiv ... 89918.html

while the theory and science and practical applications of tuning your suspension via using differing viscosities of fork oil can is revealed at:

http://www.peterverdone.com/archive/lowspeed.htm


NOTE: the following product(s) can only be shipped via ground transport (which thus eliminates the postal Priority Mail, postal Express Mail, or private carrier Expedited levels of service for this item) and cannot (and will not----don't even ask!) be shipped outside of the continental USA. Additionally, there may be a per-package weight or quantity restriction, and thus multiple-unit orders of this product may have to be shipped in separate packages and will incur additional shipping charges.

ffo3) Red Line Oil products line of SYNTHETIC FORK OILS are some of the best, highest-performance fork oils developed specifically for this purpose. They provide exceptional shear lubrication, are highly resistant to any viscosity changes, and provide excellent seal lubrication as well as very high anti-foaming properties. All of these oils are completely compatible with each other, which means that different weights can safely be mixed with each other to create "custom-weights" of fork oil for the utmost in suspension tuning flexibility. NOTE: oils, if mixed for a different viscosity, should be done in a large enough batch to provide enough oil for both front forks. You do NOT want to be running different oil viscosity's in the left and right fork tubes!

Also, do not mix different brands, styles, or types of oils........you can only safely mix forks oils together from one manufacturer!


HCP1563 Red Line high-performance SYNTHETIC FORK OILS 0W (zero weight, "like water"), 16 ounce bottle (473cc), clear. Each bottle:
$ 17.95

HCP1564 Red Line high-performance SYNTHETIC FORK OIL 2.5W, 16 ounce bottle (473cc), blue. Each bottle:
$ 17.95

HCP1258 Red Line high-performance SYNTHETIC FORK OIL 5W, 16 ounce bottle (473cc), amber. Each bottle:
$ 17.95

HCP1259 Red Line high-performance SYNTHETIC FORK OIL 10W, 16 ounce bottle (473cc), red. Each bottle:
$ 17.95

HCP1263 Red Line high-performance SYNTHETIC FORK OIL 30W, 16 ounce bottle (473cc), orange. NOTE: this oil is similar in viscosity to what most other oil manufacturers call "20W" oil. Each bottle:
$ 17.95



ffo4) PJ1 products line of TUNER FORK OILS are exceptional quality, value-priced fork oils developed specifically for motorcycle suspensions. All of these oils are completely compatible with each other, which means that different weights can safely be mixed with each other to create "custom-weights" of fork oil for the utmost in suspension tuning flexibility. NOTE: oils, if mixed for a different viscosity, should be done in a large enough batch to provide enough oil for both front forks. You do NOT want to be running different oil viscosity's in the left and right fork tubes!

Also, do not mix different brands, styles, or types of oils........you can only safely mix forks oils together from one manufacturer!


HCP10360 PJ1 products TUNER FORK OIL 2.5W, 16 ounce bottle (473cc). Each bottle:
$ 14.95

HCP10362 PJ1 products TUNER FORK OIL 5W, 16 ounce bottle (473cc). Each bottle:
$ 14.95

HCP10364 PJ1 products TUNER FORK OIL 7.5W, 16 ounce bottle (473cc). Each bottle:
$ 14.95

HCP10366 PJ1 products TUNER FORK OIL 10W, 16 ounce bottle (473cc). Each bottle:
$ 14.95

HCP10368 PJ1 products TUNER FORK OIL 15W, 16 ounce bottle (473cc). Each bottle:
$ 14.95

HCP10370 PJ1 products TUNER FORK OIL 20W, 16 ounce bottle (473cc). Each bottle:
$ 14.95

HCP10372 PJ1 products TUNER FORK OIL 30W, 16 ounce bottle (473cc). Each bottle:
$ 14.95




FORK SYSTEM SERVICE TOOLS:

Assembly and Dis-assembly Tools:

NOTE: many of these tools are available for short term rental, please see the “rental” section within the THE TOOLBOX section of our catalog at:

http://xjbikes.com/forums/index.php?threads/xj-parts-catalog-section-p-the-toolbox.44630

and review the availability and procedures in the TOOL RENTAL section.


w) Lower Fork Tube DAMPER ROD RETAINING TOOL. This long aluminum tool, with proper sized nuts on each end, is used to retain the top of the fork damper rod (in the bottom of the chrome tube) when removing or installing the damper rod retaining screw. One end has a 19mm hex and the other end has a 22mm hex, so it will fit all styles of XJ-series bikes except XJ600 Seca II, 1981-83 XJ750 Seca, XJ1100, and all XS1100 Special and Midnight Special models. This tool will make the disassembly of your upper tube from the lower tube much easier!

HCP4402 Aftermarket DAMPER ROD RETAINING TOOL.
$ 29.95


HCP9238 Aftermarket fork upper cap bolt REVERSE HEX SOCKET TOOL. This tool allows the easy removal and installation of the "inverted/reversed" hex-drive cap bolt used on the top of the inner fork tubes on all 1984 FJ600, XJ650 Turbo, XJ700 non-X, XJ750-D, XJ750P (37H) model, and all XJ900RK, RL, N/FN, and F models.
$ 12.95

HCP15939 Aftermarket lower fork tube OIL SEAL DRIVER. split “clamshell” heavy duty design features adjustable inserts that allow it to be used properly and safely install the lower tube oil seals and (where applicable) lower tube dust seals on all 35-43mm fork tubes (which covers the entire XJ- and XS-series line of bikes).
$ 39.95



Super-Penetrant Fluids and Lubricants:

Sometimes, the toughest part of working on a vehicle is battling the effects of time: seized fasteners, caused by rust, corrosion, and other factors, turns what should be a 5-minute effort into a 50-minute (or more) chore, complete with rounded-off, ruined, or snapped fasteners, e-z outs, heli-coil inserts, and more.........and that's just not right.

While the proper use of our various Anti-Seize products will prevent these nightmares from occurring in the future, you're stuck in the here-and-now, and the best way to handle these obstacles is to have the proper tools at the stand-by; and in the case of fastener seizure, the proper "tool" is a can or two of our SUPER PENETRATING LUBRICANTS at the ready; a couple of squirts, a little bit of time-----perhaps some heat for those really nasty situations----and you're on your way again, hopefully not too much worse for the experience.....

Great for use on all fasteners, fork tube cap bolts, intake and exhaust manifolds bolts, studs, and nuts, lock cylinder tumblers, or anywhere an un-cooperative fastener can be found. Can even be used to help un-seize frozen engines!

Be aware that these products are not your typical, garden-variety, run-of-the-mill "retail" type products; these are designed an used as industrial- and military-strength products, meaning they have special formulations that include a dollop more of the "good stuff" within them to solve the toughest seizure problems imaginable (the "good stuff" ingredients cost more, and it is those compounds that are left out of or reduced in concentration in "retail" level consumer products).

NOTE: the following product(s) can only be shipped via ground transport (which thus eliminates the postal Priority Mail, postal Express Mail, or private carrier Expedited levels of service for this item) and cannot (and will not----don't even ask!) be shipped outside of the continental USA. Additionally, there may be a per-package weight or quantity restriction, and thus multiple-unit orders of this product may have to be shipped in separate packages and will incur additional shipping charges.

HCP10331 Aftermarket standard-duty PENETRATING LUBRICANT, in a generous 16-ounce aerosol can. Oil-based lubricant penetrates down into spaces of one-millionth of an inch to handle the most reluctant seizures. Actually dissolves the rust and corrosion that causes the seizure; lubricates and displaces moisture to prevent rust re-formation. This product is what we use and recommend for freeing stuck fork tube cap bolts and other such challenging fasteners.
$ 24.95

HCP11974 Aftermarket super-duty PENETRATING LUBRICANT, in a generous 13-ounce aerosol can. Same as our standard-duty formula above, but also includes graphite to not only enhance and speed up the penetrant action, but also gets down into the pores of the metal for the greatest possible lubrication possible. The cat's-meow of penetrating fluids, can even be used to un-seize frozen engines or as an engine assembly lube! This fluid is also a great choice for use as a drive cable lubricant.
$ 26.95

HCP10333 Aftermarket extreme-duty PENETRATING LUBRICANT, in a generous 16-ounce aerosol can. Same as our standard-duty formula above, but also includes liquid silicone to enhance and speed up the penetrant action. This product is also an exceptional choice for use as a control-cable lubricant.
$ 27.95



Assembly Fluids and Lubricants:

NOTE: the following product(s) can only be shipped via ground transport (which thus eliminates the postal Priority Mail, postal Express Mail, or private carrier Expedited levels of service for this item) and cannot (and will not----don't even ask!) be shipped outside of the continental USA. Additionally, there may be a per-package weight or quantity restriction, and thus multiple-unit orders of this product may have to be shipped in separate packages and will incur additional shipping charges.

HCP20860 Aftermarket industrial-strength ASSEMBLY LUBE, in a standard 12-ounce aerosol can. Heavy-duty formula includes graphite to not only enhance and speed up the penetrant action, but also gets down into the pores of the metal for the greatest possible lubrication possible. Won't wash away, protect against rust and corrosion, stable from 0-degrees up to 250-F. This fluid is also a great choice for use as a drive cable lubricant.
$ 21.95

HCP20862 Aftermarket super-duty ASSEMBLY LUBE, in a generous 10-ounce aerosol can. The cat's-meow of lubricants, infused with pure moly disulfide, it goes on wet and then dries in 1-2 hours to a super-slick, high-pressure, hi-temp, bearing-like finish which provides the ultimate level of protection. Prevents rust and corrosion, won't wash off, throw off, and won't attract dust or dirt. Surfaces must be clean and dry of previous oils, etc. before application. Can even be used as an engine, tranny, and drivetrain assembly lube!
$ 24.95

HCP20863 Aftermarket super-duty GRAPHITE LUBE, in a generous 10-ounce aerosol can. The 800-pound gorilla of lubricants, it's infused with pure graphite, goes on wet, and then dries in 10 minutes to a super-slick, high-pressure, bearing-like finish which provides the ultimate level of protection. Prevents rust, won't wash off, throw off, and won't attract dust or dirt. Surfaces must be clean and dry of previous oils, etc. before application. Can be used as an engine assembly lube, bearing or bushing pre-lube, great for lock cylinders, and all metallic sliding surfaces. Use where dusty or dirty conditions render oil-based lubricants ineffective or undesirable.
$ 21.95



Fork Tube Cleaning and Polishing:

HCP28489 Fork Tubes DEEP REACH CLEANING BRUSH. This 36" long brush features polyester bristles that will reach deep inside the forks tubes to clean away grit and oil sludge residue that cannot otherwise be reached or disturbed. Has a comfortable easy-grip plastic handle and flexible twisted-wire shaft. .Use with your favorite cleaning solvents to get the insides of the fork tubes free of contaminants.
$ 39.99



ft4) These stainless-steel, bristle-wire DE-BURRING BRUSHES will work wonders on the upper cap bolt area on both the threaded and the non-threaded style of fork tubes. Tubes that use threaded cap bolt (all XJ650 Turbo, all XJ700 models, XJ750-X models, XJ750 Maxim and Midnight Maxim, XJ900RK, and XJ1100 models) should use the HCP10223 butterfly brush; non-threaded tubes can use either the HCP10222 spiral brush or the HCP10223 butterfly brush. Both style brushes have stems that are designed to be used in a standard power drill, and should be used at 850 rpm's or less. These brushes will make quick and meaningful work of the cleaning and polishing of this critical area on your upper fork tubes.

HCP10222 Aftermarket stainless-steel double-density spiral DE-BURRING BRUSH, for use on fork tubes without a threaded cap bolt.
$ 8.25

HCP10223 Aftermarket stainless-steel high-density "butterfly-wings" DE-BURRING BRUSH, for use on fork tubes with or without threaded cap bolts.
$ 8.25



Anti-Dive System Tools:

HCP12230 Aftermarket anti-dive brake plunger PISTON POPPER, for all models using an anti-dive system.
$ 9.95

HCP16049 Aftermarket fork anti-dive brake plunger assembly REVERSE HEX SOCKET TOOL. This tool allows the easy removal and installation of the "inverted/reversed" hex-drive plug used on the top of the anti-dive units on all XJ750-D, XJ750P (37H model), XJ900RK, and XJ900RL models.
$ 14.95



Fork Tube Oil Level Gauges:

HCP1728 Fork tube oil fluid level measurement GAUGE AND SYRINGE. This handy tool makes the measurement of the fork oil level easy and accurate. NOTE: the proper amount of fork oil is determined via the measurement of the fork oil LEVEL (distance below the very top of the inner tube) rather than a volume AMOUNT of oil specification. Too little oil will make the ride mushy, while too much oil makes the ride harsh (and can blow out the oil seals!)
$ 29.95



ffl4) Aftermarket fork oil measurement GRADUATED CYLINDERS. The best way to measure the precise amount of fork oil fluid is via the use of these lab-quality measurement cylinders. Available in either transparent (clear) or translucent (cloudy) durable plastic construction, they all have easy-to-read scale numerals (milliliters) and feature a "non-wetting" inner surface coating that prevents the concave "meniscus" from forming at the top of the fluid, thus insuring a much more accurate level reading. Large bases insure stability while large spouts make "the pour" easy and prevent messy drips. Very useful device to have for front fork oil changes.

HCP10741 Aftermarket fork oil GRADUATED CYLINDER, 250ml capacity, translucent (cloudy).
$ 11.95

HCP10744 Aftermarket fork oil GRADUATED CYLINDER, 250ml capacity, transparent (clear).
$ 24.95

HCP10742 Aftermarket fork oil GRADUATED CYLINDER, 500ml capacity, translucent (cloudy).
$ 12.95

HCP10745 Aftermarket fork oil GRADUATED CYLINDER, 500ml capacity, transparent (clear).
$ 33.95

HCP10743 Aftermarket fork oil GRADUATED CYLINDER, super-sized 1000ml capacity, translucent (cloudy), with convenient side handle to insure steady pouring.
$ 48.95



Fork Tube Air Pressure Tool and Gauge:

HCP9196 Aftermarket AIR VALVE STEM TOOL, handy 4-in-1 tool allows you to properly remove and insert the stem core, and also clean/chase/re-thread the internal and external stem threads.
$ 5.95

HCP9108 Aftermarket air-assisted forks LOW PRESSURE AIR GAUGE, heavy-duty 0-20 psi pencil (stick) pressure gauge marked in 1/2-psi increments, perfect for checking fork air pressures on models so equipped. Very high quality and much more accurate than standard tire pressure gauges, which is very important on the fork pressures as an imbalance between the fork pressure can lead to steering and stability issues, while too much pressure will blow out the lower tube oil seals!
$ 4.95

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