'94 VS1400 No Pressure in Clutch Lever

[Shirkni]

Hey all, I figured it wouldn't be a bad idea to get some opinions and suggestions on this issue I've been having with the hydraulic clutch system.

It started about 3 weeks ago. I went to ride to work in the morning and I started up in neutral, put it in first and it died. Tried again, same thing, so I started in first. Immediately it wanted to move forward slowly with the clutch lever fully pulled in, and would try to take off with the slightest release of the lever. Did some research throughout the day and decided to try and bleed the system. So I got some brake fluid, clear hose and my 8mm and got started. I immediately screwed up by accidentally choosing a ratcheting wrench, so when I pumped the lever a few times, broke the bleeder valve and tried to close it, it just ratcheted and I didn't realize and released the lever, sucking air back into the slave.

After getting a non-ratcheting wrench, I tried again and ran through the process with several refills of the master reservoir. At this point, I wasn't getting any bubbles and the fluid coming through the hose was clean. But that's when I noticed there was brake fluid running down onto the lever from where it actuates the master cylinder piston. Father-in-law came over a few days later and suggested replacing the clyinder. So I ordered a pair of replacement cylinders, got them in yesterday and installed them.

I ran through the process once again several times, getting a solid flow of clear fluid with no bubbles. Still no pressure in the lever, but I am seeing some fluid on and under the bleeder valve after cleaning up the area. Throughout all my bleeding, one thing I did notice was when I would close the bleeder valve and release the lever, I saw the fluid in the hose very slowly move back towards the slave. I'm beginning to think the bleeder valve is the issue, but I also think the slave could use a cleaning because the old reservoir and fluid was pretty nasty.

If anyone has any suggestions, opinions, ideas, criticism, etc. I'm all ears. Thank you!

TL;DR
Bikes dies when shifting into first. Bled clutch with no pressure returning to lever. Found fluid leaking at piston assembly on master cylinder. Replaced clyinder, bled clutch, still no pressure. Found fluid on and under bleeder valve and noticed fluid making its way back to slave cylinder during bleeding proccess. Suspected bleeder valve issue?

[Designer]

To make sure I understand,...you installed a "new" Slave Cylinder,....and, if so...the Bleeder Valve you now have on your Slave Cylinder is New,...not the old one,....right?

[Shirkni]

To make sure I understand,...you installed a "new" Slave Cylinder,....and, if so...the Bleeder Valve you now have on your Slave Cylinder is New,...not the old one,....right?

No, sorry if I wasn't clear about that. I replaced the master cylinder and lever assembly on the handlebars.

[Designer]

AHA!

If I may suggest,...first remove the Bleeder Valve and closely inspect it's Seating Surface for any scratches, kicks, dirt etc. And the same for the Slave Cylinder Bleeder Valve Seat. Also check the Threads for being worn/ stripped .

Keep in mind that Engine Heat has it's affect(s) on the Slave Cylinder Seal too. Make sure it is not leaking on you also.

[Shirkni]

AHA!

If I may suggest,...first remove the Bleeder Valve and closely inspect it's Seating Surface for any scratches, kicks, dirt etc. And the same for the Slave Cylinder Bleeder Valve Seat. Also check the Threads for being worn/ stripped .

Keep in mind that Engine Heat has it's affect(s) on the Slave Cylinder Seal too. Make sure it is not leaking on you also.

Thanks Designer! I'll be sure to check all that. Much appreciated!

[Designer]

AHA!
If I may suggest,...first remove the Bleeder Valve and closely inspect it's Seating Surface for any scratches, kicks, dirt etc. And the same for the Slave Cylinder Bleeder Valve Seat. Also check the Threads for being worn/ stripped .
Keep in mind that Engine Heat has it's affect(s) on the Slave Cylinder Seal too. Make sure it is not leaking on you also.

Thanks Designer! I'll be sure to check all that. Much appreciated!

You are most welcome! Please do, keep us Updated. We are here to Help.

[hillsy v2]

You can buy seal kits for both MC and slave cylinders - a fair bit cheaper than buying whole new units.

And reverse bleeding with a syringe is also effective.

[navigator]

An OEM slave cylinder seal is about $6.00
The slave cylinder is held in place with 2 bolts, and the piston pushes out easily.
Sand the bore with 400 emery and replace the seal, You will likely find a lot of crud in there.

[navigator]

This will also help.
https://www.harborfreight.com/brake-ble ... ke+bleeder

[sky02]

I can also suggest using a small vice or clamp if you want to do the traditional bleeding methode from the top.
. Bleeding a freshly assembled clutch line is a pain because there is no true restriction for slave piston movement. And you dont get that hard lever feling like with brakes as it works against the springs. But you can block the piston with a clamp and then after bleeding bolt the slave cylinder in.

[Shirkni]

Thanks for the suggestions everyone. I never thought about the movement of the piston when trying to do the traditional bleeding method. I ordered a replacement bleeder valve, the threads on the original looked fine (same with the threads of the slave) but it was rounded off pretty good. Won't be in til the 18th unfortunately, so I've got some waiting and more research to do.

I did take the slave off and clean up the mounting surface and all the gunk I could find, it was pretty nasty, but the seal looks fine to me. While it was off I did notice the piston moving out when I squeezed the lever, so I'm getting some pressure at least. Definitely think I'll be bleeding with the slave clamped when I get the new valve in.

[hillsy v2]

I can also suggest using a small vice or clamp if you want to do the traditional bleeding methode from the top.
. Bleeding a freshly assembled clutch line is a pain because there is no true restriction for slave piston movement. And you dont get that hard lever feling like with brakes as it works against the springs. But you can block the piston with a clamp and then after bleeding bolt the slave cylinder in.

I had to read that a couple of times to work out what you were suggesting here - but yes that is clever and will definitely give you more pressure to work with.

Having said that I have been using a syringe to forward / reverse bleed systems for many years and I find it to be the easiest way to go with the least wastage of fluid and time.

[sgtcall]

Just to add in, the seals on the master cylinder do go bad over time but you can install a rebuild kit easily. I guess to late for that but just in case.
https://www.amazon.com/0107-040-Master- ... L+Intruder

I would also suggest picking up a vacuum bleeder. It is just good to have around and it has saved the day several times.
The cheap way, but it works fine. https://www.harborfreight.com/brake-ble ... 63391.html

Or the more expensive way that also works. https://www.harborfreight.com/mityvac-v ... 39522.html

[Shirkni]

Originally, when I didn't get pressure back in the lever the first time, I thought there was air in the system still (definitely a possibility still lol) so I got that cheap Pittsburgh automotive bleed kit but the seal on the lid for the inline reservoir was bad and I would have to hold it tight for the vacuum to be present.

Definitely have thought about grabbing the mityvac but didn't want to drop too much money on the issue if I didn't need to.

[hillsy v2]

Definitely have thought about grabbing the mityvac but didn't want to drop too much money on the issue if I didn't need to.

Syringe and a bit of hose will do the same thing for just a few bucks.

[Designer]

Originally, when I didn't get pressure back in the lever the first time, I thought there was air in the system still (definitely a possibility still lol) so I got that cheap Pittsburgh automotive bleed kit but the seal on the lid for the inline reservoir was bad and I would have to hold it tight for the vacuum to be present.
Definitely have thought about grabbing the mityvac but didn't want to drop too much money on the issue if I didn't need to.

What SgtCall points out the Tool most all Professional Mechanics use for hydraulic system bleeding. Sorry to hear your Pittsburgh unit gave you trouble, but my Mity Vac works every time and it's quick, clean and neat. One of our Board members ended up going back to using this method when the syringe failed to perform as he needed.

To save you some $$$,....I have had great success buying from Ebay.

Here's an example
https://www.ebay.com/itm/195376333415?h ... R5Sa9uj6YA

[hillsy v2]

Mityvac is good for a car IMO. Not necessary for a bike. If you work out how to use a syringe you won't use anything else.

[Shirkni]

For everyones information this is my first bike, and Im compeltely new to riding, just started in May. So I apologize if any of my questions sound dumb

Correct me if I'm wrong, but with the syringe method - are you just filling the syringe with fluid, connecting a hose between it and the bleeder valve, cracking the valve and pushing fluid and any air in the line back up to the reservoir on the master?

[hillsy v2]

Correct me if I'm wrong, but with the syringe method - are you just filling the syringe with fluid, connecting a hose between it and the bleeder valve, cracking the valve and pushing fluid and any air in the line back up to the reservoir on the master?

Yes. But you can also draw the fluid back out with the syringe like a Mityvac so it's two tools in one.

[Designer]

For everyones information this is my first bike, and Im compeltely new to riding, just started in May. So I apologize if any of my questions sound dumb

The only "dumb" question is the one you do not ask,...so,..ask away!

.....Correct me if I'm wrong, but with the syringe method - are you just filling the syringe with fluid, connecting a hose between it and the bleeder valve, cracking the valve and pushing fluid and any air in the line back up to the reservoir on the master?

Yes,...pretty much. As you correctly pointed out, when you use it to push fluid, you are pushing IN air. And that is what you want out, is it not?

I've found it is best to use the tool that is designed for the job.