Slipping clutch

[coffee_brake]

Can somebody give me a run-down on what is likely a simple problem?

I have never had a slipping clutch issue till today. My bike, a Kawasaki Concours c-10 with almost 40k miles on it (original owner) had sticky shifting. As I am about to take it to CO for the AMA Women and Motorcycling conference, I was going through the system to troubleshoot. The hydraulic clutch lever and slaver clyinder were fine, bled 'em and removed them anyway, put on a new lever because the bushing was worn. But they were clean, I never let them get dirty or the fluid fouled since new.

The clutch center spring (star spring) on the Conours is a known weakness, so I pulled the clutch cover and checked the spring, all good.

I put everything back, and the clutch is slipping mightily even from 1st gear.

What did I do wrong? I made sure to put each plate back facing the same way, and in the same order, that I removed it. They sat out of oil for a day. Should I have soaked them in oil first?
They don't look or smell burnt, the bike has seen hard commuter miles but not abuse since new.

Any ideas?
There's nothing left in the hydraulic system to trouble-shoot, I think I did something wrong when I took apart the clutch.

Appreciate any ideas....

[Wrider]

Yeah they should have sat in oil before you put them back in. But it shouldn't have affected it that much. I have seen one problem that causes that. When you pull out the clutch plates did you put the last one in the grooves only deep enough for the one?

[coffee_brake]

Yep, did that...and today I yanked it all back apart. Now it's cooked and I don't know if scrubbing the steels will get it to last to CO.

Heck I don't know what I did wrong yet.

[coffee_brake]

Well I cleaned and oiled the fibers disks and scrubbed the steels disks with sandpaper on a flat plate. Put it back together and it's running OK. I have a noticeable but small amount of slippage at very hard acceleration. But overall it's fine.

This bike is going to CO this week!

[Gummiente]

What brand, type and weight of oil are you using in the bike?

[coffee_brake]

It's the same oil I've been using since new with no problems: motorcycle-specific Castro in 10/40, not synthetic. I'm aware that the wrong oil will cause clutch slippage, so I always put in the stuff made for bikes.

What is the designation on the back of the oil container that you're supposed to use that's safe for bikes? I can never remember....

[flynrider]

What is the designation on the back of the oil container that you're supposed to use that's safe for bikes? I can never remember....

It used to be that the phrase "energy conserving" in the API circle indicated that bad friction modifiers. API specs have changed over the years and you can't depend on that anymore. The safest bet is to use an oil designed for motorcycles. I use Valvoline's bike specific oil. No friction modifiers and about the same cost as regular car oil.