Clutch spring length

My clutch had been slipping so I figured the cone riding I do had taken its toll again. Ordered new friction plates and got em in. Pulled the clutch pack tonight and all the friction plates measure out to in-spec. I wanted to measure the springs but the manual only specs the spring length under a load in some special-tool/spring compressor. Is there a no-load length too that I can use to determine if they're what caused the slipping? Thanks.

Mike

FWIW, my clutch was slipping just like you say. I replaced the friction plates even though the old ones were still in spec. But the old springs were quite a bit shorter than the new springs. That seemed to fix my problem.
New springs at z1enterprises.com are about $12.