Three years ago I took my 97 Suzuki Bandit 1200 to California. Before leaving I got a little nervous about the clutch as it would only grab when the lever was almost all of the way out. I ordered up a set of aftermarket plates and replaced all of the friction plates. This did not change where the clutch engaged.
I rode to california and back with no issues, and then the bike was off the road until just a few weeks ago. I put the bike back on the road and after a couple of rides, the clutch started slipping. I barely made it home, and by the time I got home, it almost felt like it was an automatic!
I took the clutch apart and could find nothing obviously wrong with it except the fiction plates were close to the wear limit. I checked all the steel plates for warpage and the spring heights as per the suzuki service manual. I ordered a new set of OEM friction plates, and new springs while I was at it. Put it all together and took it for a test drive. It works, but I think something is wrong with it. The clutch only engages at the very end of the lever travel. If I push the bike really hard with the bike in gear and the engine off, I can get the bike to move without the tire slipping or the engine turning. I think it's the clutch slipping.
I'm 100% sure I put the clutch back in properly (double checked with the manual as I was doing it). I'm suspicious that something else is wrong as the last clutch didn't last very long at all.
I'm working on two possibilities. One is that the problem is in the hydraulic circuit (this clutch is hydraulically activated). The idea being if the slave cylinder didn't retract properly it would take some of the spring pressure off of the clutch. I took apart the slave cylinder and found some gunk and a bit of corrosion on the cylinder. I'm just taking a break before taking apart the master cylinder too.
The other is I measured the new OEM friction plates before putting them in and they were all close to the bottom service limit despite being brand new. Possibly the whole stack is too thin? If this is the case, there are two thicknesses of steel plates in the stack: could I swap out a thin one for an extra thick one? The service manual doesn't say a thing about doing this, but it seems logical.