Clutch master cylinder nightmare

[Hooli]

Jeez Hooli, why are you so anti gravity ?   

Our gravity works in the correct direction old bean.

[Gsxjohn]

Gents, clutch still not working🥵 got new seal kits for master cylinder and slave incase I'd got bad set. Both fitted and free moving in respective cylinders, started to bleed it and all going well and suddenly master cylinder piston doesn't return and sticks.
I've fitted new Hel clutch hose as well.
Anyone come across this?

[Del]

@Gsxjohn  - hi fella just read through the post

have you tried bleeding from the master cylinder - as in the banjo bolt at the top - Ive fitted more than my fair share of refurbished calipers and you can get an amazing amount of air bleeding this way

Clutch as teh clutch line is so long you could have air in this aswell

Worth a try mate good luck

Del

[Gsxjohn]

Del, I've tried reverse and from master cylinder. Even had banjo off slave cylinder till fluid through. There's something causing the master cylinder locking up and not returning when handle released.

[Del]

could it be a duff line that is collapsing when under pressure - you could try putting old lone back on and see if that rules the issue out

if the line is the only thing that is different then I would look at that

[seth]

As @Del  said
Dont assume anything .
Put back to standard and give it a try then try the new lines.
My top tip for bleading the clutch is to use a clamp in the slave cylinder piston so it can't move as when you blead it the piston moves against the clutch springs .
I find it makes the whole job easier.

[Eric GSX1400K3]

Gents, clutch still not working🥵 got new seal kits for master cylinder and slave incase I'd got bad set. Both fitted and free moving in respective cylinders, started to bleed it and all going well and suddenly master cylinder piston doesn't return and sticks.
I've fitted new Hel clutch hose as well.
Anyone come across this?

Have you measured the master cylinder od and the housing id? Sounds almost like the cylinder is getting skewed in the bore.  I think air in the system is unlikely if youve bled from the banjo as well. Ive got Hel lines on mine and no issues, doubt also that a line is collapsing. 

Didnt use a clamp, found the clutch plate spring pressure is enough to allow to bleed.

Maybe post some pics of the master cylinder and bore and resevoir?

[grog]

Gsx, Subaru clutch bleed has sim prob. Trick is to get outlet above master cylinder, only way to do it. Maybe a length of clear tube off slave bleeder, fastened up high. Tiny little master pumps until clear fluid, no bubbles. Re attach to slave, more very short stroke master pumps. My opinion only, master not coming back because air in system is compressing, no fluid pressure to return it.

[KiwiCol]

Good call Grog, I had trailer brakes like that fairly recently. 

I'd fitted a new master cyl n buggered if I could get it to bleed properly, never had issues before. Solved it by making the outlet higher than the master cyl, easy on a trailer, bit harder on a bike, but will work the same.

[gsxbarmy]

That's a good call @grog - I've had issues before depending on how the handlebars were turned and found with the clutch if the bars were on hard left lock it was a so and so to get all the air out. Front wheel facing straight ahead and with bars level sorted that.

[Hooli]

That's a good call @grog - I've had issues before depending on how the handlebars were turned and found with the clutch if the bars were on hard left lock it was a so and so to get all the air out. Front wheel facing straight ahead and with bars level sorted that.

When doing the clutch or the front brakes I turn the bars until the fluid in the reservoir is level with the edge of it.

[Gsxjohn]

Many thanks to you all for the advice greatly appreciated. Tried all the above, even slave cylinder hung from rafters to get above master cylinder...took it off the bike first🤣
No air in the system🥺
Refitted and tried clutch, pushrod moves about 5mm, when released the clutch lever doesn't fully return there's about 5mm free play.
How much free play is normal?
With clutch in and in gear I can't turn the back wheel.
The engines been out for about 2yrs.

[Del]

sorry if Im revisiting old ground - you say the engine has been out for about 2 years
- when did it last run because if it has been sitting for 2 years not running and being used the clutch plates can seize together and therefore you wont be able to move the wheel when in gear (I recently had this with a bike that was sitting a year) I removed the clutch and soaked in oil for 24 hours refitted and all was good

the above could also be the reason your clutch lever isn't returning all the way

Del

[Gsxjohn]

Del, I've been thinking that way too.
The more I've gone over everything I've done and been suggested it would be the next logical step🥺 Bugger!!

[grog]

Unfortunately i agree,plates stuck together.