1986 VFR 750 Clutch Question

I'm looking at a VFR 750 a guy is selling. He is the original owner and the bike has 27K miles on it. He said he parked the bike about 8 years ago, and last year he noticed a puddle under the bike. All the fluid ran out of the clutch. He said the bike ran fine when he parked it. There is no pressure on the clutch lever, which makes sense with no fluid and the system full of air. It is not leaking from the resivor, but looks like the clutch housing. Has anyone seen this before, and is it a costly fix? The bike is in amazing shape and worth getting back on the road, but if this is an expensive fix I want to get the buying price reduced. Any help would be appreciated. Thanks.

 

You may find this hard to believe but the slave cylinder is the same on all generations . I think I have a couple sitting around if you need one.

 

A simple fix, just replace a cheap, easily-accessed rubber seal in the slave cylinder.

You need to ride the bike to check out the transmission, but without a working clutch, impossible.

Tell him that you'll buy the bike if the clutch hydraulics get fixed and you can test ride.

It's worth a try to simply refill the mc with dot4, then bleed the system, as leaks from clutch are usually slow, and you might easily restore enough fluid pressure for a ride.

 

x2 on what Squirrel man said.

I bought my 86 VFR750 with a snapped clutch level and had to tow it home. After getting it running and riding it around I noticed the shifting isn't very smoooth......sometimes crunchy.

 

Thanks for the info. I'm in the process of selling my 1974 Suzuki GT 750, and it should be finalized this week. I'm going right over to get this VFR. I have never seen a VFR or any sportbike this old in this great of shape. I have owned many bikes, but never a VFR. I remember them as a kid walking through the dealship in the 80's. I can't wait to post pictures and start riding it!

 

did it improve after changing the oil? if not what kind of oil are you using?

 

Nope. :frown:

I'm using Motul 5100 Semi-Synth (10w40) with a Honda Oil Filter.

 

Ruroh, doesn't sound good slow.

 

I'm hoping it's just something in the Shifter assembly and not in the tranny itself.

I thought it might be an issue with the Hydraulic clutch but Squirrelman took a quick look and said the Hydraulics felt good.

 

Normally I don't try to fix a bike before I buy it. A non-running bike is usually cheap - as soon as you can ride it the price goes up considerably. Personally I would take the risk and try to get it cheap. If the guy seems decent then his word should be ok.

 

I'd be more worried about...

Not the clutch. As was said, it is very simple, but a bitch to bleed. You may need to clean and flush out the master cylinder and slave and line, hell, even replace it all if the bike is in good shape.

But the real bear will be the carbs. If sitting for years, the gas has varnished the insides, bowls and needles and small orifices. Plan on removing the carbs and at least do a bottom end job. That was all that was needed on my barn find VFR that sat for some time, but I had to take them off and on multiple times. Getting bowl gaskets and other carb parts was fun also. Some of the O-rings also leaked gas on the black plastic tube that crosses between the carbs. Some cheap o-rings fixed that right up but finding the leak was an adventure. But in the end, she is now as pristine as the one I bought new back in 1986. Hope you are not paying too much for it, and have a place to work on it. Not including your time, it will be worth it if you can get it for less than say $1400.

 

Well I did pick the bike up. I changed the slave cylinder seal, and rebuilt the master cylinder. I'm still getting no pressure build up. It is not leaking anywhere, and the line is fine. I have bled the thing until my hand hurts!!! Any suggestions??

As far as the carbs that will be my next project. The guy gave me four new carb kits, I just want to get this clutch working first.

 

loosen up the slave so it is about 1/4" - 3/8" from the case, pump up the clutch lever then retighten it in a cross pattern.

 

Since the hydraulics are a closed system, if there is no air in there and no leaks it will work. I'd check to make sure the pushrod is in there (!) and is giving resistance. You never know what might have happened to the bike, so don't make too many assumptions.

 

mstakern: you might have to rebuild the master cylinder if you can't build up any pressure at all and you bled it with a vacuum pump.

 

Pinch the line just below the master and see if it builds pressure. They can be a bitch to get started.

 

When I flushed/ changed my fluids I had the same problem you are having with the clutch. No bubbles!. I let it sit overnight and no luck. Then I figured it out. The clutch lever... I had it adjusted close to the grip. Dont need much clutch when shifting a VFR, but you need it to bleed... Back off the clutch handle and you get a much bigger swing. As soon as I did that, boy did I have pressure and bubbles. Before I did that I was getting no where fast.

 

I did loosen the slave about 1/4 inch and was able to build pressure, but once I tightened it and pulled the lever 5 or 6 times I had no pressure. Again no leaks, and I just rebuilt the master cylinder. I think my next step will be to bleed it with a vacuum pump. I also did adjust the lever out all the way.

 

I'm still struggling with this one. Just a few quick questions to make sure I'm bleeding this thing the right way. When bleeding is the resevoir cap and diaphram off or on? I get pressure if I loosen the slave pump the lever and then tighten the bolts then a few pumps later no pressure. I even went back into the master cylinder to make sure I had everything back together correctly. I also got some silicone grease for the slave seal and reinstalled. The manual said brake fluid or silicone grease. I have not tried to bleed the system with a vacuum because I do not have one yet. I'm not sure if that is my answer??????

 

:focus::welcome:This may sound strange. When I worked at a Volvo truck dealer, We serviced the European truck clutch slaves with a rig made up of a windshield washer pump. This was setup to flow brake fluid up from the ww pump to the slave to the master, this would eliminate the bubbles and the need for pedal bleed, this is also the way to do this as I have done i this way for years.
Any one here ever done this way before?
1) Trico WW pump
2)1/4x4ft clear washer hose. to be connected to the fluid (drill the brake fluid cap insert the hose. Connect to the input of the pump, output to the slave open bleeder. Make sure the master is semi empty .You need a turkey baster empty the master..
3) 5ft 14 g insulated wire,black,red.
4) 2 insulated alligator clips to be soldered to the clips, and to the pump wires wired for proper polarity. B+, Neg- for the battery connection. also a momentary switch (Radio shack, Napa, Auto Zone) and some shrink tube for insulation..
5) New dot 4 Brake fluid.
6) Power point, Battery 12 volt source.

Make a mount for the pump, fluid container. source out the bikes battery connect and go to bleed the system. this will also do any bike brake system to. have fun with this fun hobby, Mike R...
So I hope you have the skills to make this up it's fairly ezy..