Two instances caused clutch fluid leaks.
First was bought a used Clutch slave. No doubt it's was sitting around dry without fluid. Cleaned it up and installed it. Soon noticed the drip under the bike. Clutch reservoir quickly looses fluid level.
Second, After a day long ride through snow country. Sand used on the roads for traction on ice. Picked up a fine sand dust every where on the bike. The next week started noticing drips under the bike. Soon the clutch reservoir became low.
The first instance the seal in the slave became hardened. Not signs of wear just less then pliable. The way the seal uses fluid pressure to force it's outter ring against the cylinder wall. The hardened rubber wasn't flexible enough to get a good seal and leaked.
The second instance a fine dust got lodged between the seal rubber and cylinder wall. Fluid would escape that littlest space where the dust was. Secondarily contaminates make it's way into the cyinder. Blackening the brake fluid all the way to the reservoir.
Both repaired by replacing the 1 - Seal Cup Part # 23163-06B00 @ $3.55
Introduced in 2004 is a rubber cover that protects the slave cylinder from contaminates. Can be retrofited on any year Busa. Should help keep the fine dust from causing leaks. 1 - Cover part # 23166-02F20 @ $6.26
Pull left side fairing, Gear shift to gain access to the sprocket cover. Clean the Slave cylinder using only brake fluid. Fine #0000 steel wool for any burned in stains. Note the orientation of the seal. Imagine how the fluid pressure will force the seal outward. Use brake fluid as a lubricant to assemble the parts.
