Clutch :)

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Twotimer56

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Hi everyone, quite new here,also fresh owner of the vmax,struggling with the good old clutch problem.
Really hoping that I will get some help couse slowly I turn to mad max and will light my bike on fire :)
After a slave cylinder rebuild,and master cylinder replace,2nd was thinkind that it might be faulty, I tried to bleed the clutch, ha ha,I tried with no luck.
Also notice that the fluid in the rezervoir is getting dirty and blurry after 10-15 pumps.
Chacked the slave 5 times,no leaks,have no idea what to do.
After today,that was my 5th day of working on this,3-4h/day I kinda lost interest,anyone any idea?Thank you in advance
 
Ok.....first things first....did you bleed the Master cylinder before you hooked the line up to it? If not your supposed to put some fluid in it, and put your finger over the outlet hole, (where the line bolts up to) and pump the lever until it will push your finger off....and you dont see any bubbles come up from the hole at the bottom of the master cylinder. After that, hook the clutch line up and start bleeding the system. Bleeding it the old fashioned way, can be a pain in the ass, but Ive done it...but you have to pump the master cylinder 50-150 times before you will start building pressure to be able to bleed it.

This thread talks about reverse bleeding it using a syringe. Quite a few people here have used it with pretty good success.
http://www.vmaxforum.net/showthread.php?t=3928&page=2

When its bled, I would COMPLETELY change out the fluid because its dirty and you dont know how long its been in there.
 
Mine is exactly this way. Not sure why the discolouration of the fluid. I had replaced the OEM line with a Galfer a few years back and it seemed fine for the first couple of seasons.
There's no leak at either the master or slave, and the clutch is now engaging about half out on the lever.
 
Don't bother trying to bleed it down, do the 'reverse-bleed' pushing fluid up from the slave cyl bleeder fitting. Use fresh fluid of course, do not re-use the old fluid. Start by emptying the master cyl as much as possible, put a few cc of fresh fluid in there, enough to cover the two holes and wet the floor of the chamber. Then begin to push brake fluid from the slave cyl bleeder upwards. You should see the fluid begin to raise the level in the master cyl and it will carry sediment and old fluid w/it to the reservoir. Empty the fluid in the reservior as it fills except for a bit to cover the two holes on its floor, and begin again to push fluid from the slave cyl upwards. As the line becomes filled, you will see tiny bubbles coming from the master cyl holes in the floor of the reservoir. Usually at this point the line is pretty-well purged. Throw the cap on and then rapidly fan the lever as far as it will go, squeeze/release. You should quickly feel the pressure build to move the diaphragm spring in the clutch, 'resistance.' I like to set my stock levers w/the screw barely having any freeplay, maybe 1-2 mm.

If you now remove the master cyl lever and "CAREFULLY(!)" and slowly squeeze the lever you should see tiny bubbles coming from the small hole closest to the front banjo bolt of the master cyl. If you squeeze too-quickly or too-far, you will shoot brake fluid all-over the front of your bike! That's the remaining trapped air working its way up, bubbles rise, right? Your friction point should be well before the halfway-point, where the clutch diaphragm spring resistance is felt, and full release about 2/3 of the lever travel. Replace the cap. Any well-stocked hardware store should have the conical, flat machine screws in either allen or phillips, I suggest buying a half-dozen to replace your probably knackered-head stockers, and that leaves you 4 for the other side of your handlebar and another replacement set for what you just did.

The tool to do all of this is a 60 cc syringe w/about a 3" clear plastic tube on the end, I use a small hose clamp to hold it to the brake bleeder. Sometimes I wrap the slave bleeder bolt w/a few wraps of teflon, to stop any air infiltration while pushing the fluid.

Enjoy your new clutch bleed.
 
+1
That's great, and why it's awesome to be on this site!
Specific, detailed information!
I've never tried the reverse bleed, but I will be this weekend.
Question though. Does anyone have an idea where the "greyish" sediment is originating from? The master piston? Seal? If so, might this mean the master is on it's way out?
 
+1
That's great, and why it's awesome to be on this site!
Specific, detailed information!
I've never tried the reverse bleed, but I will be this weekend.
Question though. Does anyone have an idea where the "greyish" sediment is originating from? The master piston? Seal? If so, might this mean the master is on it's way out?

Ive always wondered if it was from the lines themselves? Ive always been told to replace stock rubber lines every five years due to deterioration and stretch. If you stock lines are flexing, then full pressure isnt going where you need it to...to the clutch, brakes...etc.
 
Brake fluid is hygroscopic-it attracts and holds water in solution, along w/the particulate matter from the brake pads which works its way past the piston seals, along w/dirt. This sludge is what you see when you're flushing the system.

For some reason, the traditional method of using a Mityvac doesn't work as well for me on the clutch, but it does OK for the brakes. Nowadays I am apt to use either method for brakes, but only the reverse-flush for the clutch. It will save you literally hours of futzing w/the clutch hydraulics.

The master cyl is like a light switch, either it works, or it doesn't. Either side, clutch or brake. Changing brake/clutch fluid once a year is a good preventative for long service life. When the seal of the master cyl goes, it either bleeds internally, resulting in inefficient travel for the desired effect, or it leaks past the rear seal, closest to the lever pivot. Then you see brake fluid leaking down the lever, and dripping off the ball end of it. It's worth a try to change the fluid &bleed your system if you find excessive lever travel, but you should be prepared for rebuilding the master cyl or replacement. As cheap as they are, I usually just replace them any more. I think of it as cheap life insurance.
 
Thanks Fire medic. I just went out to the shop & did this. went from 90% out till engagement to 60%. I'm happy with the results. So,...I figured I'd do the front brakes as well. Didn't gain anything on the leaver, but, It made it firmer to squeeze . win, win.
 
You're welcome, we all learn from each other. And, parts are available from others on here to keep you on the bike.
 
Thank you everybody,manadged to do the reverse bleeding but after squeezing thru a bottle of juice,the clutch started to work at the werry end when I pull in the lever.Is that normal?
 
No, you still have some air in the line then, or if you did manage to purge the air, you need to repeatedly squeeze the lever to get it moving fluid. I call it 'fanning' the lever.

Some of the guys will swear that there's a trap for holding air up by the banjo bolt, and that by loosening the banjo bolt a bit, and continuing to bleed, you'll get rid of the last bit of air. I've not had to do this myself, but you could consider trying it. Be aware your brake fluid could leak everywhere w/the banjo nut holding the hose to the master cyl loose! Wrap the junction w/a clean rag or lots of paper towels, a spring clamp should be able to hold that tight to trap any leaking fluid.

Sounds like you're almost there. I would first try 'fanning' the clutch lever, w/everything sealed up, and see if you get the friction point to move to the middle of the lever travel. If that doesn't do it, then I would return to bleeding.

Once you've removed all the bad old discolored, contaminated fluid, you could re-use the new fluid if you wanted, but if it's not clear like water, don't re-use it.

Thank you everybody,manadged to do the reverse bleeding but after squeezing thru a bottle of juice,the clutch started to work at the werry end when I pull in the lever.Is that normal?
 
Like all above. Keep "fanning" the lever and look for little bubbles. Once all of the "grunge" and air is gone it will work. The friction zone is very short. Mine is at the 3/4 mark. As above...I bleed yearly. It's quick. Just enough to flush the lines. You're close.
 
Finally all sweet,clutch is working properly, I just have one more question, where the hell is the small copper washer going,the one that fell out when I removed the clutch lever.
 

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