Weak/No Clutch

[Bucko]

there is also information somewhere something about a check valve or something, in the m/c, sticking and not working well.

There are two holes in a master cylinder - the larger one allows fluid to flow (in one direction only) from the reservoir to the circuit as required.  The small one - the bypass hole (I'm sure that's not the official name) allows fluid to creep back into the reservoir when the plunger is at rest which allows for some fluid expansion and, in a brake system - allows the pads to float a bit.

If the small hole is plugged, there's no way to relieve a build up of pressure in the circuit, which for a brake circuit results in a constant application of the brakes, or in a clutch circuit, results in the clutch not fully engaging (i.e. slipping).

[greenbarn]

What Pilgrim said....   That's a common problem for the Drifters- clutch plates sticking after storage.

However, you said the clutch is still spongy after you've bled it.  That make me think, possibly, the m/c isn't working as good as it should.  Here's the clutch tips page, which has several articles:
https://www.vulcandrifterriders.com/forum/index.php?action=links;cat=24

there is also information somewhere something about a check valve or something, in the m/c, sticking and not working well.   I do not think you would be able to manually, by hand, push the clutch, although I haven't tried so can't say for sure.

Easiest thing to try first is what Pilgrim said, rock it hard on the ground to see if it will break free.

[Pilgrim]

either your plates are stuck (push it on the ground with it in gear and clutch pulled in to see if they come unstuck) or you need a new spring. Spring is not hard to change, there are write ups and part numbers here on forum (mods and accessories link).
Welcome to forum, a lot of info and help here.

[Q2569]

Hey All,
Having an issue with a 1999 Drifter 1500 clutch? I went for a ride this morning and fired her up, pulled in the clutch, placed into 1st and it lurched and died. I had issues getting it back into neutral but did after rocking back and forth. Wheeled into the garage and placed on the stand. Noticed the clutch felt spongy so I pulled MC off cleaned up real good, re-bled and it still feels spongy but noticed that the clutch is not disengaging the transmission when rolling through gears (up on the stand not running). Pulled slave cylinder off and it is stroking in/out as expected. The clutch rod cannot seem to be pushed by mortal means, but not sure if it can be done by hand. I also noticed that just trying to push transmission through the gears it is a bugger to get from first to second but will roll through all the rest of the gears fine but when down shifting from second to neutral to first, it is not as smooth as she used to be. I think the clutch MC/SC seem to be working and fluid return in MC is good. Before I tear the casing open wanted to throw it out to the masses to see if anyone has had something like this happen to them.
Thanks to everyone
~Q