help clutch problems

[GixerBoy]

Hi I have an NC21 (old VFR400) which has a hydraulic clutch, i have bled the line and the clutch is still really soft if there at all, any advice what i should check next, any help would be appreciated

[DEATH_INC.]

Could be the master(prolly) or the slave.Sometimes the pipe will have a tiny airleak that'll cause you greif.

[vifferman]

Hi I have an NC21 (old VFR400) which has a hydraulic clutch, i have bled the line and the clutch is still really soft if there at all, any advice what i should check next, any help would be appreciated

This is a common problem, whenever you take the side cover off. It's caused by the throw rod not sitting right in the slave cylinder (or sometimes there's a spacer that's been left out). You either have to bleed the hell out of it, or take it off and check the slave cylinder seals aren't leaking. Unlike brakes, there's not much pressure on the clutch lines, so it takes a lot of pumping to bleed it, unless you have a Mityvac or similar.
It's also easy to get airbubbles in the line that don't want to go out, as you're trying to push them downhill (and as I said, you can't build up much pressure, plus the clutch M/C is small, so doesn't shift much fluid with each stroke).
There's some easy (well, easier) way to bleed the clutch in these situations, but I can't for the life of me remember. I do know that almost every time I've had the side cover off my last four bikes, I've had no clutch afterwards and had to faff around with getting the pressure back.

[GixerBoy]

thanks guys, yeah it seemed like i had bled it properly but there must still be air in the line. It was working not to long ago cause i was push starting it, but it has sat around for a little while and slowy got softer.

[vifferman]

To get rid of the air bubbles in the top of the line, pull the clutch lever in just a very small amount (few mm), and gently tap the clutch reservoir and/or cylinder body and/or top of the clutch line with a small spanner or screwdriver. If you do this with the cap off, you should see bubbles come out of the aperture at the bottom of the inside of the reservoir. The idea is that you are puling in the lever just enough to open the valve, but not so much that you've closed off the return part of it. Repeat as necessary.