RC51 Forums banner

1 - 15 of 15 Posts

·
Registered
Joined
·
311 Posts
Discussion Starter #1
Well, I put on new levers and noticed some weird play on the clutch side and a co-worker pointed out I was blowing bubbles into my reservoir every time I pulled the clutch in. On closer inspection there was a tear on the boot for the button that pushes in the valve into the master cylinder. I've got a "rebuild kit" on the way, but has anyone else run into this issue? I thought it was kind of weird and it's kind of a heads up if any of you feel your clutch lever is feeling funny.
 

·
Super Moderator
Joined
·
6,485 Posts
The boot you mention is just to keep contamination out.
You have air bubbles in your lines probably due to a worn cup seal and O-ring on the master cylinder piston.

It can happen to anyone when they wear enough.
I've had the same happen to clutch and brake master cylinders on my cars.
The repair kit should correct the problem.

Just be sure and keep everything clean, and don't drip any brake fluid on paint or plastics.
 

·
Registered
Joined
·
311 Posts
Discussion Starter #3
Yeah, I've bled my lines a couple times since I bought it (I know it's not necessary to bleed the lines so often) and wondered why the feel got so weird. I rushed the order so I'm hoping I'll be getting the rebuild kit tomorrow at work. My co-worker said it could leave me stranded so it has me a bit worried. However, I'm quite happy with the Titax levers I got. I still wish I had the option of a long clutch lever, but I really like having a short brake lever which is more important anyways.

And forget my plastics, I plan on getting new ones over the winter. I bought my bike knowing little about plastics and bodywork stuff and now realize the plastics on my bike are craptastic.
 

·
Registered
Joined
·
8,663 Posts
SubSailor has you covered there. that boot was torn on mine too. A new one came in the rebuild kit. The reason you are seeing bubbles is because one of the cups on the inner piston is torn enough to allow air thru. And it def can leave you with no way to dis-engage. It happend to me. At a traffic light. In fact, I had several traffic lights to negotiate to get the bike home. no bueno.

I would take the slave cylinder off too and inspect those cups/seals. Since the one's on your master are going out...
 

·
Super Moderator
Joined
·
6,485 Posts
With the overhaul of the master cylinder, you're gonna have a lot of air in the system.
Does the master cylinder seem like it's trying to pump fluid?
There's not much to the system, but getting all the air out can be a pain.

One thing we tried with my brother-in-law's goldwing, was squeezing the lever and securing it in that position over night.
The air bubbles collected and we were able to bleed them out.

Some bikes have bleed screws at the master cylinder and slave cylinder ends.
I think that would have been a great idea for this time as well.
 

·
Registered
Joined
·
311 Posts
Discussion Starter #9
I got this weird feeling that I messed something up with the rebuild, but I followed the diagram in the repair manual exactly, hell, I just did it just the way that weird drill-looking thing, rubber grommets and spring came out of the cylinder. Anyways, I've got the lever tied down and the system closed so I hope it works in the morning.
 

·
Super Moderator
Joined
·
6,485 Posts
Were you getting any leakage at the master cylinder?
And did it feel like it was trying to pump or apply pressure to the system?
If all else fails, you may need to disassemble the master cylinder again to inspect what might be the problem.
 

·
Registered
Joined
·
8,663 Posts
Ok, somethings gotta give. Starting at the top, are you sure you have that little bushing in your clutch handle is properly lined up with the push rod? the one that goes inside that torn boot? does it line up properly with the center of the master piston?
Next, does your handle return properly? It should come all the way back out, if the master piston and spring is right.
Ok, your squeezing the lever in. Assuming you have ample fluid, and the cups are installed right on the master piston, then you have to be pushing fluid downward. Unless there's air. If you're convinced there's no air, then the next thing that has to happen is the brake fluid is pushing your slave piston inwards. But you would feel some pressure.

Since you feel no pressure, I can only think of three things it could be.
Your system isn't getting the pressure to start with, such as mis-installed piston cups, or your push rod isn't in right.
Or you still have air somewhere.
Or you have a leak. Did you look real good at the bottom of the gear cover? If your slave were leaking you might see it there. Check the banjo fittings, check the clutch hose, blah blah :)

If you need a couple good diagrams of the master and slave internals, here's a couple links. I think sp1 and sp2 are the same, but not positive.

http://www.bikebandit.com/houseofmotorcycles/2000-honda-rvt1000r-rc51/o/m2474#sch96152
http://www.bikebandit.com/houseofmotorcycles/2000-honda-rvt1000r-rc51/o/m2474#sch93165

This site has high prices, but good diagrams. They expand big and clear.
 

·
Registered
Joined
·
311 Posts
Discussion Starter #13
It was massive amounts of air I think. I just went down to my slave cylinder, took it off and pumped it a few times... in essence did what I was doing with my lever except with the slave cylinder diaphragm thing. I'm gonna go take it for a test ride, but my oh my my clutch is already feeling tons tighter now. I guess that was a bit reckless, but jebus it's 2 AM already and I got work in the morning. Bah, I can never sleep that well when my baby's sick anyways.
 

·
Registered
Joined
·
8,663 Posts
If you're still up, and you have the system closed, zip tie your clutch handle to the handle bar. Then in the morning, carefully bleed that top banjo bolt. Don't spill.
Bleed your slave with a couple more squeezes, then test ride. If you got good pressure on your clutch handle, that is.
Good luck.
 
1 - 15 of 15 Posts
Top