Do i need a clutch master cylinder overhaul kit?

[Storleer]

These 2 pictures are taken from where the clutch lever pushes into the piston that goes into the master cylinder. I can see that the rubber boot there is torn. The lever also looks a little worn there. What do i do with this? Get a rep kit i guess, but should i also replace the clutch lever as well?

I have noticed that sometimes the clutch is difficult to fully disengage as in the lever not going all the way to the handlebar. I also removed the clutch slave and sprocket cover, but it is difficult to tell if there are any leakages from the slave unit because the cover, slave unit and everything around the sprocket was caked in an insane amount of dirt. Maybe i'll just get a rep kit for the slave as well. Is this a difficult job?

[Flynt]

These 2 pictures are taken from where the clutch lever pushes into the piston that goes into the master cylinder. I can see that the rubber boot there is torn. The lever also looks a little worn there. What do i do with this? Get a rep kit i guess, but should i also replace the clutch lever as well?

I have noticed that sometimes the clutch is difficult to fully disengage as in the lever not going all the way to the handlebar. I also removed the clutch slave and sprocket cover, but it is difficult to tell if there are any leakages from the slave unit because the cover, slave unit and everything around the sprocket was caked in an insane amount of dirt. Maybe i'll just get a rep kit for the slave as well. Is this a difficult job?

Replace the lever...  mine looked much better than that and wouldn't disengage a decent condition clutch.  Randy sells them... 

The slave is easy...  buy a new one from RPM and bolt it on.  You'll thank me later.

Frank

[Tor-King]

I would highly recommend to rebuild the master.  If it is difficult to activate, a new rebuild kit will do wonders (along with the lever). Often this is maintenance that is overlooked. RPM is a great source: https://www.rpmracingca.com/proddetail.asp?prod=M%2FC%3AClutchrbkit

And...as Flynt suggested, the slave could/should be replaced.  That said, there is a rebuild kit for that as well.

Dean

[Storleer]

Thanks for answering

So i'll get a new lever and a new slave unit. I forgot to mention, i have a 84 fj1100. It seems that RPM do not have the master rep. Kit for my bike?

[copper]

https://www.rpmracingca.com/proddetail.asp?prod=M%2FC%3A1100CLTCHMCKIT

https://www.rpmracingca.com/proddetail.asp?prod=Clutch%3A5EA-16381-00%3A36y-16381-00

[Storleer]

Ouch, that MC rebuild kit was more expensive than i expected.

Maybe a silly question, but will there be a big difference between getting a repair kit for the SC rather than replacing the entire unit?

[Storleer]

After having a closer look i think i have found the culprit. The spring in the picture doesn't look right?

[racerrad8]

Ouch, that MC rebuild kit was more expensive than i expected.

Maybe a silly question, but will there be a big difference between getting a repair kit for the SC rather than replacing the entire unit?

There are a couple of different slave cylinder rebuild kits and yes they are cheaper that a new replacement.

O.E. Yamaha Slave Seal Kit
Slave Cylinder Rebuild Kit

But the condition of the slave bore is what is usually the deciding factor on rebuilding or replacing.

I do not stock the 1100 clutch lever but I can order it in without any issue.

Unless you are looking to keep the bike all stock, your best bet is looking for a used FJR1300 master cylinder on eBay.

Randy - RPM

[Storleer]

Ouch, that MC rebuild kit was more expensive than i expected.

Maybe a silly question, but will there be a big difference between getting a repair kit for the SC rather than replacing the entire unit?

There are a couple of different slave cylinder rebuild kits and yes they are cheaper that a new replacement.

O.E. Yamaha Slave Seal Kit
Slave Cylinder Rebuild Kit

But the condition of the slave bore is what is usually the deciding factor on rebuilding or replacing.

I do not stock the 1100 clutch lever but I can order it in without any issue.

Unless you are looking to keep the bike all stock, your best bet is looking for a used FJR1300 master cylinder on eBay.

Randy - RPM

I ordered a new clutch slave unit at RPM, and a new clutch handle on Ebay - got a NOS one for $15. Unfortunately the M/C rebuild kit at RPM was out of stock.

When replacing the Slave unit, this is bolt off/bolt on + opening the bleed valve on the new one, right? I've never done this before. From what I understand I should get something like a turkey baster/bleed tool to put on the bleeder valve, and open up the M/C reservoir, and while sucking out the old fluid carefully pour new fluid into the M/C fluid reservoir before it is empty and start sucking air.

I don't know which fluid is in the system, so I will replace all of it while i'm at it. DOT 3/4/5 brake fluid?

[FJmonkey]

How you bleed it can vary. It helps to fill the slave before you bolt the hydraulic line back on. Use new crush washers, cheap insurance against leaks. Then the party begins. You can bleed it the old school way using the lever to push fluid from the master. Having a catch bottle to prevent air getting back in is very much needed. Putting some Teflon tape on the bleeder fitting threads also help get a better seal. You can invest in speed bleeders, seems like a good idea, never used them myself. Or use a syringe and push and or pull fluid while adding/removing fluid as required. Or get the Mighty-Vac that many here say good things about.

[Pat Conlon]

Yep, just as Mark said.

Use DOT 3/4 fluid (Unless the system have been converted to DOT 5)
Start with a full slave.
Use 2 new crush washers on the banjo fitting.
Teflon tape the bleeder screw threads.

To remove the old fluid from the reservoir I just use some paper towels to (carefully) absorb the old fluid. Carefully as in No drips (see below)  
Take this time to clean the m/c reservoir. Remove the bottom splash plate and clean out the crud collected below the plate.
 

Three methods can be used
1) Vacuum pump (MityVac) the easiest.
2) Reverse bleed (bottom up) next easiest. You need a syringe to inject the fluid at the slave bleeder port.(might as well buy a MityVac)
3) Traditional top down bleed. Takes the longest. In some cases overnight for the air bubbles to travel up the line to the m/c. Patience is key.

Be careful with DOT 3/4 It will eat your paint and bleach your black fairing inner panel. Lot's of towels and a spray bottle of water to neutralize the hygroscopic brake fluid is a good idea.

[Flynt]

Three methods can be used
1) Vacuum pump (MityVac) the easiest.
2) Reverse bleed (bottom up) next easiest. You need a syringe to inject the fluid at the slave bleeder port.(might as well buy a MityVac)
3) Traditional top down bleed. Takes the longest. In some cases overnight for the air bubbles to travel up the line to the m/c. Patience is key.

IMHO there is another path...

4) Before mounting Slave, do the top down method (3 with Slave full of fluid and fully compressed), but push the Slave piston in SLOWLY after you pump it out with the lever.  This technique puts all the air in the line and then uses the fluid in the Slave to push the air out.  In the final stages of this, you'll see a bubble free volume of fluid being pumped back and forth between Master and Slave.  I have seen Randy do it this way as well and it works as well as a MV.  I've also done it this way with great results.

Frank

[Pat Conlon]

Well that's interesting Frank, thanks!

So, seeing as though you are the first to post this (that I know) you get to name the method. Something descriptive.

We will memorialize it over in the clutch files section.

[Firehawk068]

IMHO there is another path...

4) Before mounting Slave, do the top down method (3 with Slave full of fluid and fully compressed), but push the Slave piston in SLOWLY after you pump it out with the lever.  This technique puts all the air in the line and then uses the fluid in the Slave to push the air out.  In the final stages of this, you'll see a bubble free volume of fluid being pumped back and forth between Master and Slave.  I have seen Randy do it this way as well and it works as well as a MV.  I've also done it this way with great results.

Frank

This is the recommended method for bleeding the hydraulic clutch on my Firehawk (LT-1 with the T-56)
It is how I did it on the car before bolting the slave to the bellhousing, and it worked well. 

[Flynt]

...you get to name the method. Something descriptive.

Not sure it has a name, but I learned it from a mechanic long ago.  Having seen Randy do it that way, I think we should name it the RPM method...  Maybe the Reverse Pressure Method?

Frank

PS - I left out a key bit...  some Master Cyls have a plate in the bottom of the reservoir, I think put there to keep a geyser of brake fluid from spraying out accidentally.  If you've got one of them, you need to pull it out so you can see the bubbles coming out when you compress the Slave.