Most riders don’t think about their bike’s clutch at all. Sure they use it every time they ride. They may even do the right thing by adjusting and lubricating the cable assembly. But, really, think about the clutch? Never-that is until it starts to get cranky and becomes grabby, or just gets lazy and starts to slip. Although you can often get away with only replacing the clutches fiber plates, we usually replace all the plates and springs to assure that everything is within specs. Barnett Tool and Engineering (9920 Freeman Ave., Santa Fe Springs, CA 90670; 562/ 941-1284)supplied us with new Kevlar® friction plates ($80), steel plates ($35), and springs ($18) for our Virago 750. A clutch cover gasket set us back another $12. After gathering all the parts, any mechanic-even a novice-can replace a clutch in about an hour. The tools required to replace the clutch in our trusty Virago 750 were: 10mm, 14mm and 17mm sockets; a 5mm allen socket; 4- and 6-inch extensions (although the 6-incher will do); a ratchet; a torque wrench; a 14mm wrench; a big flathead screwdriver (a technical term); and gasket sealer. Of course, you also need a shop manual and a clean place to work. Music is nice, too.
Start by leaning the bike away from the clutch side, so the oil will stay put when you get the clutch cover off. (If you’re replacing the clutch after it has failed, you should change the oil and filter-since they’re most likely contaminated with clutch-plate particles.) To get to the Virago’s clutch cover, we needed to remove the brake light spring, the brake pedal (note the alignment marks on the pedal and spindle), and the right peg mount bracket. Next, using a 5mm allen, loosen all of the clutch cover bolts in a crisscross pattern. Pick a point on the cover (mark it with a grease pencil if you’re forgetful), remove the bolts one at a time in either a clockwise or counter-clockwise direction, and place them in order on a clean shop rag.
To remove the case cover on the Virago, remove the oil filter cover, then locate the notch between the clutch cover and the engine case (slightly in front of the oil filter cover). Gently pry the cover free of the case with a screwdriver. (Although some people may say you can save the gasket if you remove the cover carefully, we recommend buying a new one to assure an oil-tight reassembly.) Next, remove the clutch pressure plate bolts with a 10mm socket. Take note of any alignment marks on the clutch pressure plate and basket that may need to be matched on reassembly, or make your own with a marker.
Remove the pressure plate and set it aside. The throw-out bearing in the center of the basket may fall out as the pressure plate is removed. If it does, check for alignment marks and place it back in position. Using the tips your fingers, or a pair of curved picks, remove the clutch plates one at a time and stack them in exactly the same order. Note the plate order for installation. Incorrectly stacked plates can cause premature clutch failure.
The importance of how carefully parts must be set aside can’t be overstated. The clutch plates are zip-tied together to maintain their order, prior to inspection. If fasteners are arranged neatly and logically, reassembly of the clutch pack and covers will be much easier for novices and experts alike.
Since the length of the bolts varies by almost 1/2 inch, trying to figure out which bolt belongs in which hole is time consuming and terribly dull. (“Nope, doesn’t fit there. Not here either. Dang. Only twelve more to go….”)
While the clutch is apart, inspect the clutch basket’s inner and outer hubs for wear. If any notches or grooves are visible in the fingers or splines, the basket probably needs to be replaced. Consult your shop manual or local mechanic for information on how to remove the basket’s hubs.
Remember, installing a new clutch into a worn basket may result in abrupt clutch engagement or clutch chatter. If you don’t plan on replacing the steel plate s with the fiber ones, check the steel plates for any signs of wear – such as discoloration or scoring. Measure the steel plates’ thickness to make sure the plates are within suggested tolerances. Make sure the plates are not warped by placing them on plate glass. If any of the plates do not lay flush to the surface, or can be rocked in any direction, replace the plates as a set. Because we hate doing the same job twice, we chose to replace the steel plates even though the stockers showed no signs of wear.
Before assembling the new clutch pack, soak the fiber plates in fresh oil for five to ten minutes. When sliding the plates into the clutch basket, be sure to arrange fiber and steel plates in exactly the same order as the old clutch pack. If you are unsure, the innermost and outermost plates are usually fiber-but check your shop manual before proceeding. The steel plates are usually made of stamped metal, with one rouned edge and one sharp edge. Some mechanics say to make sure steel plates are installed with the sharp edge facing the pressure plate, or excessive outer hub wear may result. Barnett says it doesn’t matter if the sharp edges face in or out, but all of the steel plates must face the same way.
Place the pressure plate over the clutch pack. Install the springs into the pressure plate and screw the bolts in until snug. Be sure to install the springs and bolts in a crisscross pattern for even pressure on the plate, Using a torque wrench, tighten the bolts-again in a crisscross pattern-to the shop manual’s specified torque (5.8 foot pounds in the case of our Virago). While some people may proclaim with pride that they never use a torque wrench, we’ve found that properly torqued assemblies(clutch and otherwise) fail much less frequently. Aagin, although the OE springs showed no signs of wear and exceeded 40.2mm minimum length specification, we chose to replace them with Barnett springs. While the Barnett springs are stiffer and require a slightly firmer pull at the lever, the company says that the additional tension provided by the springs helps make engagement of the Kevlar®plates more progressive.
Clean off any remnants of the old gasket with a knife or gasket scraper. Be careful not to score the sealing surface. Chemical strippers, like naval jelly, can help in particularly tough cases, but be careful to keep these chemicals from all painted parts. Make sure all gasket pieces are removed. Clean the mounting surfaces with a solvent, such as contact cleaner, to make sure no oily residue remains to interfere with gasket adhesion.
Apply a thin coat of gasket sealant to both gasket mounting surfaces. If you are unsure of where to apply the sealant, look at the shape of the gasket itself. We’ve found that pliable, non-hardening sealant works best on covers like the clutch cover. After allowing the sealant to skin over for a couple of minutes, place the new gasket (remember the $12 you save by reusing the old gasket will seem inconsequential if the cover leaks oil) in position on the engine case. The sealant should hold the gasket in position. Make sure the dowel pins in the case (if any) are in place before mounting the cover. Reinstall the clutch cover bolts in the same order that they were removed, but do not tighten more than finger-tight. Once all the bolts are installed, torque them to the factory specs in a crisscross pattern. Finally, install the footpeg bracket, the brake pedal (don’t forget the alignment marks), and the brake light spring. Let the bike sit for an hour or so, to allow the gasket sealant to set, before starting the engine. Your new clutch will most likely engage in a slightly different lever position, but you’ll also notice it engages much more positively than the cranky old clutch you removed. Since the new clutch will shed more friction material initially, change the oil after a few hundred miles.
Virago Clutch Replacement Submitted by Evans Bradfield
Copyright©Motorcycle Cruiser Magazine – April 1998