Take a look at our YSR Clutch Kit
Friction Plates
The most important part of the clutch are the friction plates. They take most of the wear and tear, not to mention abuse! Friction plates are designed to be an item that is expendable. They are supposed to wear out, as a result they need to be replaced occasionally. How often will depend on you. If you are racing, it's suggested every 3 races. This is due to the need of feathering the clutch to stay up on the power band. If you are doing normal street riding, you can figure once a year. If you are doing abnormal (?) street riding, .i.e., lot's of wheelies, burn outs, etc, you can expect to replace the clutch quite frequently.
Friction plate life can be somewhat lengthened by doing a few simple things. First and foremost, use a clutch that is of the highest quality. Be sure all related components are in excellent condition. This means ALL related stuff. Your clutch springs, hub, pressure plate, outer basket, push rods, clutch cable, actuator mechanism, and the lever and perch. The correct amount of oil, and the correct type and viscosity of the oil is a must! Also keeping the oil fresh is a plus. All of these items will affect how well the clutch works and the "feel" of the clutch.
Metal Drive Plate
Proper clutch operation requires all of the clutch components to work well together. The YSR has one metal plate. It must be in good condition to operate properly. Check it for correct thickness, and flatness. It can have no hot spots or discoloration. If any of these criteria are not correct, replace it!
Springs
Weak or fatigued springs are a major area of poor clutch action. Weak springs will cause slippage and premature wear. All four springs must be the same type. Excessively heavy springs can cause also problems - including, but not limited to - premature actuator failure, excessive stress on case covers, etc.
Clutch Specs:
| Friction Plate Min/Max Thickness | 2.7mm-3.5mm |
| Quantity | 2 |
| Metal Plate Thickness | 1.5mm +/- 0.1 |
| Metal Plate Warpage Limit | 0.05mm |
| Clutch Spring Free Length (Min) | 28.2mm |
| Push Rod Bending Limit | 0.2mm |
| Pressure Plate Screws Torque | 4.3 ft/lbs |
| Clutch Boss Nut Torque | 32 ft/lbs |
| Transmission Oil | 600cc (No Synthetics) |
The stock from the factory YSR clutch is a barely adequate unit. The springs are way too weak and the friction plates are lacking in a big way. We would strongly suggest replacement with our clutch kit. However, just replacing the clutch is not enough. PROPER ADJUSTMENT is a must!
Clutch Adjustment (we will work on getting a video ready for this, as well):
| 1. Loosen cable length, adjust locknut |
| 2. Loosen clutch, adjust lock nut |
| 3. Turn/adjust until lightly seated |
| 4. Turn out/adjust 1/8 turn |
| 5. Tighten/adjust lock nut |
| 6. Adjust lever free play (2-3mm) |
| 7. Tighten cable length lock nut |
| 8. Put rest of stuff back on! |
There are two push rods and a ball bearing involved in the clutch actuating process. The push rods tend to get a big dimple in their ends over time. They are inexpensive, and replacement will enhance clutch action.
Lube it. Adjust it. Life is good! Use this Cable Luber if you'd like!
The Clutch Kit, when properly installed and adjusted, will greatly enhance the delivery of power to the rear wheel. Don't leave home without it!
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