Pumped up Clutch

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I think I'm just gonna suck some fluid out before I head out today. My reservoir was really full. Should I do it so I see a tiny bubble in the sight glass?

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OK. No dice. I rode up to one of the schools I work at. About 12 miles. By mile 4 I could make the motor spin up with no acceleration using anything more than 1/4 throttle. The lever was rock hard, but the level of fluid did not rise in the reservoir. I'm using cheap whatever O'reilly Dot4 fluid. I think I might suck all the fluid out of the reservoir and start over reverse bleeding the system. These are the EXACT symptoms I had before I changed everything out for the PCW kit. There must be something else going on. I know that Sean didn't see anything too strange when we had my motor apart last month, and I've only ridden about 180 miles since then.

Maybe something happened when I changed levers? With the broken FJR lever, everything seemed fine. The aftermarket one was really tight to install. Maybe the ratio is a little different and it's always putting pressure on the plunger in the master.

I'm pretty sure it's not possible, but has anyone ever had the little brass donut mess up a galfer line?

Here's what happens:

Motor heats up -- no problem.
Leave the house to ride-- no problem cruising.
Blip the throttle to test in 3rd and 4th gear -- no problem.
Ride two more miles -- test again with throttle blip -- clutch slips and catches when throttle is mostly closed again.

It's like I get one heat cycle, and the system just gives up. It does feel the same as a blocked secondary hole. I'll work on that in a bit, but this is really frustrating. Any ideas?
 
Maybe you should try mounting a stock master cyl & lever.

If I was working on your problem, this is what I would do. I am not a pro mechanic, just a hobbyist (like the Victory ads...:biglaugh:).

1] Disassemble a stock master cyl. Clean it and make sure the small hole is totally-clear, I use a needle (both holes are clear). Reassemble it and bench-bleed it to see if you get pressure. Turn it threaded hole-up, pour in fresh fluid, and then throw-in a bolt to close the threaded hole. You want to have NO air pocket, so as you thread the bolt, you may spill some brake fluid. I use brake cleaner in an aerosol to clean-off spilled fluid.

Either temporarily replace it on your handlebar, or clamp it into a vise, and work the lever. You should have a firm lever (you filled the reservoir too, right?) You can purge whatever small amount of air there is around the plunger assy by partially-squeezing the lever and watching the "fizzy bubbles" (small, "tiny-little bubbles") pour-out of the front, small hole in the reservoir. Partially-squeeze and release, repeat until no-more "fizzy bubbles."

2] Service the slave cyl the same way, remove, disassemble completely, remove all corrosion on the piston where it moves in the bore, clean the square o-ring land of the slave cyl body (another Dremel tool job, nothing else except maybe a media blast cabinet does it as-easily and quickly). Lube the entire square o-ring w/fresh brake fluid & reinstall it into the slave cyl body's kerf (the machined groove for it). Now coat the piston sides which slide into the slave cyl body where they would contact the o-ring. Press it into the slave cyl. w/ your fingers. You should be able to do this and to pull it back also w/your fingers.

3] Pour fresh brake fluid into the slave cyl. Use one of your spare hoses to now connect the rebuilt master cyl and the slave cyl. Bleed the system as-if it was on the bike. Put a piece of wood and a c-clamp into the side of the slave cyl where the slave cyl bolts to the engine. You are going to be limiting the movement of the piston, the c-clamp does that.

4] Test the complete system for function. Let it sit, come-back and do it again later. It should develop pressure, it should move the piston, and the piston should move as-far as the c-clamp allows it. You're simulating the clutch pressure plate moving. It should work exactly the same after walking-away and coming back to test it again.

If the lever now is loose, and doesn't develop pressure, you have either air entrapped, or a leak, look for the wet spot, especially on the master cyl seal plunger where the plunger contacts the lever. Any brake fluid here, and you have a bad master cyl seal.

5] Install your known to be correctly-functioning system onto your bike. Make sure the lines are clear, and not internally-collapsed. That goes for the rigid line too. I have had internally-collapsed brake lines on cars, bikes, and trucks. This just happens to be a clutch. Bleed the system using the reverse-bleed system, pushing brake fluid up from the slave cyl bleed nipple, into the master cyl. You may have to siphon some of the excess fluid out of the master cyl. I use a 60 cc syringe & a 2-3" piece of small-diameter clear plastic tubing, hose-clamped onto the slave cyl bleeder nipple. Take your time, you aren't in a race to empty the syringe, and you are dealing w/small orifices.

6] Remove the clutch cover and verify that the clutch pressure plate moves when you actuate the clutch lever. You have to loosen the friction disc stack so you can shift gears. You could just say, "I feel the diaphragm spring tension," and let it go at that. We are working on a process of elimination here. Remove the cover, and verify the pressure plate moves.

7] Now you should have a clutch which is operational.
 
I removed my aftermarket lever and installed stock fjr. Everything seemed normal so I tried the eBay lever again. I think the little brass barrel was binding or something. It's like the plunger was getting depressed at a weird angle and it was hanging up. Worked great on my evening test ride. We'll see what happens tomorrow.

I guess the moral of the story for me is to grease that barrel before reinstalling levers.

My local dealer was actually helpful and told me he'd put an eBay lever on his R1 that was a little off in measurement from the stock ones and it would lock his front wheel with barely a touch due to the plunger being pushed just a little and blocking the fluid return.

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