Hard to push, dangit.

So I'm 5'9, 170 and like to think I can move reasonably heavy objects with relative ease.

But my 'new' XJ750 is just damn hard to push. I mean DAMN hard.

Yeah, I was in neutral. Bike was warm. Tried it with clutch in and out; no difference.

I searched, and found this:

The front brake felt good, but the rear brake... well, it didn't feel like it was doing much (or, possibly, much that it wasn't already doing?)

So... what with that and the delamination problems, I guess it's time to crack open the rear brake, eh?

EDIT: Front /brake/, not front PAGE. Sheesh.

 

Try loosening the brake control. I've got a 650 Midnight Maxim and the rear brake is adjustable with a nut by the drum. If you can loosen that to feeling like it isn't gripping at all you may be able to diagnose it without taking the wheel off.

Then again, removing the wheel and fixing the root cause of it will likely be the inevitable solution. Hopefully this is diagnostically helpful! (Please throw in any professional help, for you seasoned experts)

 

Hi Flynn, It's not likely the rear brake is at fault though you should pull the rear wheel and check for "DELAMINATION". Put your bike up on the center stand and see if the rear wheel turns freely, if it does, raise the front wheel off the ground and see if that one spins freely. If they both do spin with ease then check your tire pressure. If your front wheel has a good bit of resistance the problem is likely to be in your master cylinder( there is a small port which tends to get plugged) and there is a great forum on this subject, so do a search.

 

No gotta be more than tire pressure. Unless you were trying to push it up a 20%grade then something is binding/grabbing. On a flat surface I could push my XJ with one hand and once it's moving it's just gonna roll away from me if I let it. My driveway is about 2% grade and when I flip up the kickstand I have to keep my foot on rear brake to keep from rolling backwards.

I would suspect that you have a brake shoe stuck to your drum - could be delamination or it could have rust bonded to it. Could be bad adjustment, could also be your front binding. Check that freeplay like suggested and dial it down from there.

 

While you've got it on the stand to see if they roll freely, test the bearings out. Grab the wheel and try to move it back and forth. Have a buddy hold the opposite end so you don't tip it over. Test both wheels.

Even after checking the rear to see if it rolls smoothly, check the rear brake for delamination. Don't check it by waiting until it locks up on you at 60mph.

Front wheel: Take the MC off and clean out the hole with a couple thin strands of electrical wire. This hole is microscopic, you'll only need one or two pieces of the thinnest wire. DO NOT use anything that will make the hole any larger. While you have the MC off inspect all other parts for repair/replacement if needed.

I suspect this to be your problem, but if it's not then you will need to rebuild the calipers also. It's not a bad idea (read: highly recommended) that you do this anyway, along with replacing the original brake lines.

 

You should have "cracked open the rear brake" BEFORE RIDING THE BIKE!

That's the whole point of delamination warnings.

The other thing that commonly happens on these bikes is that the front calipers begin to hang up, as the pistons get bound up in the bores. There is 30 years' worth of crud and dried brake fluid built up in the channels behind the seals. They are trying to tell you they need to be rebuilt. The seals in the caliper and master cylinder were supposed to be replaced every two years, and the brake lines every 4 years. Granted that's a tad conservative, but 30 years is way beyond any designed-in margin.

There is only one way and one way alone to make a 30-year old Yamaha brake system safe, and that's to completely rebuild it. It simply has to be done.

 

Stopping is not something worth taking a chance on. Take the time to go ahead and rebuild your bake system and you will thank yourself for doing so.

 

Yeah. The peace of mind from rebuilding the brakes is worth far more than I'll pay for the parts.

 

Just my $0.02 here....

I have to admit my bike is also extremely difficult to push....now I AM getting a little long in the tooth....but I still got a little "Old Man Strength" in me...

When my bike is on the center stand my rear wheel spins freely by hand...same with the front.

I just chalked it up to the 500+ lbs. By no mean is my "easy" to push.

 

Are we talking like, "man, this is heavy! and it's rolling slowly!"

Or are we talking "Grab the handlebars, YANK backwards, move 1.5-2 inches"?

Because mine's definitely the latter.

 

Flynn, have you put it on the center stand yet? do you have a center stand? we're not getting the picture here.

 

To restore FULL function to the Front Brakes, ...

You have to Overhaul the Caliper AND Mount.
The Caliper "Floats" on O-ring'd Rods that fit into Receiving Holes drilled into the Caliper.

You can bring-back good braking on the bikes with the Single Piston and Floating Caliper's by Overhauling the Caliper.

Undo the Fork Mount from the Caliper Body.
Take off the Dust Covers and Clean-up the "Rods" or "Pistons" that the Caliper floats on.
Remove the O-rings and get the Rods cleaned-up by shining-them-up with strips of 600, 800 & 1000.

The BIG move is cleaning-up and really putting a finish on the "Cylinders" that accept the Mount to the Caliper.
After cleaning it out of the dried-out grease, that makes you need to muscle the brake lever to get some brakes, put a new finish on the Inside Diameter.
Tightly rolled-up finishing papers, that fit-in tight, will do the trick.
600, 800, 1000 & 1500.

On this part ... wet the 1000 and 1500 with WD-40 and twist it in there for 10 or 12 revolutions.
Change-up after doing 10 or 12 because the paper clogs-up.

Once that's refinished ... clean-up both sections.
Lube with ~~> Synthetic WATERPROOF Grease.
Join the parts.
It won't be easy ... you have to push-in and pull-out until the air "Burps" out and the two parts re-seat.

Don't forget the Dust Boot!
Now, that Caliper is definitely going to "Float" the way is should!

You got a front brake; now!

 

Hey guys.

After some grunting and cursing that led me to a video on how to put my bike on the center stand, my bike is now on its center stand. (It helps when you use your leg and not your back.)

Tires were inflated to ~15psi each. I inflated both tires to ~26psi. This made it suck less, but not much.

Rear wheel spins freely with no noise except for what I suspect is the usual sound of the rear end and shaft.

Front wheel doesn't spin freely when lifted off the ground. I guess I know what I'm doing next.

On a related note, I'm buying a motorcycle jack; jacking up an XJ750 with a 3-ton automotive floor jack is for the BIRDS.

For comparison, I grabbed the ~400lb Virago that I have sitting next to my XJ750, and walked it backwards and forwards with no effort.

 

Hey Flynn, first thing to try is crack the bleeder valves, this will release the pressure. Without touching you brake lever, see if the wheel spins, if it does the problem is in the MC, if the wheel is still resistant to turning, it's the caliper. Also if there is someone there to help you, have them put weight on the back of the bike to raise the front and slide in a jack stand; I think it will fit under the bottom engine mount bolt. I'm not sure if the oil filter housing is strong enough to support the weight, so steer clear.

 

Awesome, thanks. Thanks for throwing ideas my way - if you (or anyone else in this thread, haha) finds yourself in PA, I owe you all beer. =)

I'll crack the bleeder valves first thing tomorrow and go from there.

 

Heed Steve's advice. The filter housing is aluminum. The only thing you'll accomplish by putting a jack stand under that housing, is a broken housing.

 

Trust the experts here - Do a COMPLETE front brake overhaul. My 650 front brake locked up, and the master cylinder AND caliper both needed a rebuild.

Another suggestion, don't stagger the work on the front brakes.. bleeding them is a major P.I.T.A. You have to bleed the front brakes when you rebuild any part of the system, so buy the caliper rebuild kit, the MC rebuild kit, and the brake lines. Do them all together and you'll thank yourself when you can push it with practically zero effort, AND when you are on it and need the brakes to work (and release) exactly when you need them to.

What part of PA are you in? I'm about 20 minutes southeast of Philadelphia in NJ and always looking for new people to ride with / work on bikes with.

EDIT:
You really don't want to use a jack if you can help it, there is too much risk of damage. The center stand was installed for a reason, and is WELL worth using. If you need the front end off the ground, add weights to the back end. Tie a Cinder Block to a rope and loop it over the back of the seat.

I've found taking my front wheel off tends to displace enough weight from the front end to keep the front in the air. Not that this is always practical, but just a side thought!

 

Because the Bike's weight is so well distributed; you can make a Gig to support keeping the Front-end raised for Nose-related work.

Cut a square of 1/2" Plywood the size of a Milk Crate bottom area.
Glue a square of Carpet Remnant to the Plywood.

Use this Square between the Floor Jack and Bike to lift the Bike's nose off the floor for Bearing Tests and quick Wheel Tests and raising the Bike for setting upon Jack Stands.

 

My center stand isn't sufficient for elevating the front and my back tire is already lightly touching (not sure why but I suspect the center stand is bent or rotates backwards too far). So I ran a 1/2" steel bar (like some jacks come with, but any steel bar would work) between and underneath the front engine mounts and placed two jacks on each bar end that stuck out from the motor. Then I could jack it up w/no damage & could also level the bike by taking one stand up slightly higher than the other. Made removal easy & checking bearings easy. Once up I placed a jack stand under each side to stabilize.

You can't put a standard motorcycle jack under (EDIT-sorry might have steered you wrong on your bike since the exhausts aren't all the same) a 550 with the stock exhaust collector in place-it covers the bottom and is not supported or strong enough to take the load.

I've seen a picture on here in some thread where someone else jacked theirs up this way. It works and no danger of damage or coming off. Next time I do it I will snap a pic and post it. The rear I jacked up using the swing-arm as a jack point.

I think we need a fabricator to develop an XJ specific jack or jack accessory that would allow us to easily do this. I would pay for it since I don't have a welder or welding skills.

 

THIS is the only way to go. YOU NEED to completely rebuild them; otherwise each thing you leave undone becomes the new "weakest link" in the system. Rebuild only the M/C and you'll begin having caliper problems, or vice-versa. Rebuild the calipers and M/C but don't replace the lines and you'll pop one.

Completely rebuild the brakes; take the opportunity to upgrade to stainless lines; and be safe and be done with it. Otherwise, like many of the other "systems" on the bike, it will force you to do it item by item as failures occur and frustration mounts. If you don't wind up wrecked in the process.

 

I'm having this issue on one of my 550s right now, and I thought this was the cause.

It's not.

One (or possibly both, but one for sure) of my centerstand MOUNTING EARS is broken loose from the frame crossmember at the top and allowing the stand to rotate too far.

Start a new thread to discuss this if you wish, we don't want to hijack a brake rebuild thread.

 

Thanks bigfitz I will check into that. No hijack intended, just trying to help him with jacking up his front end to attend to his issue. Believe it or not I found adjusting my vavles easier than figuring out the safest best way to jack up the front.

Back to the issue - when I rebuilt my brakes the whole system was very dirty with ancient brake fluid. I completely drained everything, replaced rubber with stainless, returned my MC reservoir to like new, rebuilt MC and Caliper, soaked and wire brushed bolts, and used a vacuum pump to bleed the system. It took almost a full bottle of brake fluid before it all came out nice and clean. Now the front brake system is undeniably the newest, nicest part of my XJ550 and it would (but I won't) do a front end wheelie now. Also the rear brake switch was way out - it comes on immediately now. Rear brake is also brand new, and also works too good.

Oh and fun fact the little rubber cap that covers the bleed screw was inside the caliper if front of the union bolt! Guess a PO was confused about where it went.

 

Hey, guys! Checking back in again; this week has been crazy.

So, I've learned a number of things:

a) The previous owner handed me a stack of receipts. They were all for state inspections.. Christ.

b) I put the bike up on the center stand, weighted the back and tipped her back just a little. Wheel won't spin. So I removed the bleeder screws on each brake caliber; wheel still won't spin.

So I removed both calipers (this required a hammer) and will be rebuilding. Also, it's the original brake lines (yay!) so i'll be replacing those. I'll probably also do the master cylinder in January.

Just in case someone gets this thread and still doesn't know what the hell to do.

I'm in central PA, up by Penn State. =)

 

See Flynn I knew you could do it! I hope you didn't whack those calipers too hard, they are aluminum. Make sure you don't have cocked pistons, if you do, use a "C" clamp and gently apply pressure until it goes back into the caliper. Then use compressed air, GENTLY to expel it from the caliper. DO NOT PUT YOUR FINGERS OR ANY PART OF YOUR HAND BETWEEN THE PISTON AND THE CALIPER FRAME WHEN YOU APPLY THE AIR PRESSURE!

 

I don't actually have a source of compressed air I'd seen some folks using grease guns and then being hypervigilant about cleaning the caliper out; thoughts on this?

If I do, I'll at least get it on video for you

 

[quote="flynnski]...I'd seen some folks using grease guns and then being hypervigilant about cleaning the caliper out; thoughts on this?
[/quote]

The "grease gun trick" works every time and is only slightly messy, not dangerous. It works in "slow mo." The bleeder screw is the same profile as a grease nipple; all you need to do is replace the brake line junction bolt with a solid bolt. I've used this method successfully a number of times when compressed air was doing nothing.

You DO have to be hypervigilant about cleaning out the channels the seals sit in, or the piston will hang up.

 

Hi again, all!

So I bought a grease gun ($16) and some grease ($1.49) at Tractor Supply, removed the brake pads...

...actually, I'd like to complain a moment about the brake pads. You know how there's a cotter pin that keeps the slide pin from sliding out of the caliper and scattering your brake pads all over the road? Yeah, the previous owner had replaced one on the right caliper WITH A PAPER CLIP. I stared at that for a solid 30 seconds in abject horror before removing it with pliers.

Anyhow, the grease gun clipped right into the bleeder valve; a m10x1.25 bolt sealed off the bolt where the lines go, and several squeezes of the pistol grip later, I had two pistons out of their calipers.

A few notes for people who may try this after me:

* ONE: Lithium grease gets everywhere. No, no, you don't understand. IT GETS EVERYWHERE.

* TWO: The piston will be removed from the caliper very slowly, with a great deal of very slowly increasing force. It is entirely possible to eject the piston in a slightly crooked fashion and push it up against the caliper. Don't do this. Definitely don't get your finger between the piston and the caliper.

* THREE: Did I mention this shit gets everywhere? Because you just don't understand how much grease there is.

So yeah, the walls don't look bad, and the pistons look fine. No real scoring; some accumulation of crap which I'll be taking off with a Dremel, after I figure out how to remove all this grease. I guess I'll be replacing the seals too, because while they don't look terrible, there's no excuse not to do it now.

Which brings me to my next question: How do I get rid of all the grease now occupying my calipers? Do I just wipe it down/q-tip it to death, then apply degreaser?

 

There is brake degreaser that is sold in all auto parts stores, pick a big can of the stuff and after you have a good majority of the grease out, then flush the piston bores and the bleeder ports with generous amounts of degreaser, you can also use pipe cleaners in the small ports. You want the stuff with 1,1,1, trichloroethane, or something that sounds like that. Also you want to wear rubber/ latex gloves when using this as it will remove from your hands all skin oils.

 

Brake fluid and a tooth brush works great as a cleaner for brake parts. I know, I didn't believe it either until I tried it. Then get a spray can of brake parts cleaner and spray the heck out of 'em.

 

I said it was messy; and also that it would for sure work.

LOTS of shop towels, and flush everything out with Brake Cleaner.

 

So between being out of town for weeks for the holiday and waiting for the rebuild kit to come in the mail, re-organizing the garage and getting a new workspace together, I haven't had time to mess with the calipers until this weekend.

I've got nearly all the gunk out of the brake cylinders, and what's left isn't big enough to be felt with my fingers. I've gone through a can and a half of brake cleaner, a couple cubic inches of #0000 steel wool, and a toothbrush. There's some discoloration and possibly some gunk on the cylinder walls and in the sealing area, but I can't _feel_ it and everywhere else is actually shiny, so I'm calling it good.

What's bugging me right now: Getting the dang pistons back in the calipers! Any tips on keeping them straight? I thought I got one stuck in just a little sideways, and I hate to admit it, but used vice grips through a doubled-over paper towel to (unsuccessfully) extract it. I managed to scratch the outer wall of the piston in doing so. Might have to get a new one.

Gentle encouragement with a rubber handle popped it out, but jeez. Any tips for getting these things in?

 

They should pretty much slide in with some firm finger pressure.

Did you lube them with either brake assembly lube or fresh brake fluid first?

The piston will be OK unless you scratched it where the seal "sweeps."

Did you get the channels the seals sit in ABSOLUTELY RELIGIOUSLY CLEAN? If there's ANY crud left in the channels, the piston will get "grabbed" by the new seals and not move freely.

 

Yeah, with fresh brake fluid. I don't have any brake assembly lube. (I do have a whole ton of lithium grease... but i take it that's bad.)

I repeatedly soaked the channels in brake parts cleaner, hit them with steel wool, used a dremel plastic brush, and scrubbed with brass brushes. It's still not a mirror finish, but it's much, much better than it was.

These are the only things between me and going for a ride. Kind of frustrating.

 

Correct, don't use lithium grease; fresh brake fluid is fine.

If there is still buildup in the seal channels that refuses to come out (usually in the "corners") a quick "kiss" with a propane torch will turn the most stubborn crud to crumbly dust that can be much more easily removed.

Besides bleeding an empty system, getting the seal channels clean is about the biggest PIA in rebuilding one of these calipers.

 

Dangit, I don't own a propane torch. I have a set of tiny screwdrivers that I'd been using; I guess I could get a little more emphatic with those.

I guess I can pop the seals back out and give it another once-over... So basically if I'm feeling resistance a) it's not straight or b) it's not clean? I hate to come back to this same point, but I definitely should not be needing to play with heat/cold or apply mechanical pressure (c-clamp, press, etc) to put these pistons back?

thanks again

 

When I rebuild my Front caliper i used some small plates of steal and a c-clamp trick is try to keep it straight when your putting it back in.

 

Huh, propane torches are $17.99 at Tractor Supply. I may have to rethink my approach.

 

they're a whole lot cheaper when you say the following quote to your neightbor....." hey, can I borrow yer propane torch fer a minit?"

Dave Fox

 

Problem solved; I put a socket in the piston and tapped lightly with a rubber mallet until they seated nicely. Everything is now bolted up and attached.

Next problem: Master cylinder reservoir. I don't know who decided to put that there. Why did anyone think that was a good idea? How did the guy who thought that up keep his job?

In my head, I imagine that guy's boss delivering a message like this: "Miyamoto! This is unacceptable! You bring dishonor upon yourself! and your family! And your children! Ninjas will kill you in the night, Miyamoto!"

Anyway, I'm going to go read the FSM instead of unbolting things at random.

On a related note, a screw fell inside the fairing. It's gone, isn't it?

EDIT: Haynes says to use the filler hole. Huh, look at that. A filler hole on the right side of the reservoir. I'm still angry.

 

After reading this post, I'm definately rebuilding my calipers and MC and replacing the brake lines. I have the same problem moving my bike. Hope I don't find a paper clip holding mine on!!!!

 

Okay, sorry to rely on you guys so much, but this is really befuddling.

I modified a funnel (yay dremel!) to fit inside the filler plug, but when I poured brake fluid in, it overflowed almost instantly.

So I removed the cover to the reservoir, and here's the current situation:

The master cylinder reservoir is full, but when I pull the brake lever, no fluid comes out of the bleeder valve, and the level of fluid in the reservoir does not decrease.

When I pull the lever, the cable actuates the master cylinder, and I can see movement. When I crack a bleeder valve and actuate the lever, air comes out. But brake fluid does not appear to be flowing from the reservoir to the master cylinder.

I've successfully removed the reservoir cover (thank god for ratcheting screwdrivers that bend in half), and confirmed that fluid is not moving from the reservoir to the master cylinder.

I've also pulled a line upstream from the calipers and confirmed that only air was being pumped (but it DOES build air pressure if I cover it with my finger).

I'm failing to comprehend something fundamental, I think. Thoughts?

Oh, and Myron - Definitely do your brakes. The wheel now spins freely, haha. that was definitely the problem.

 

I just sheared a union bolt while checking torque specs. Two things:

a) Union bolts on brake hoses get torqued to 18.8 ft-lbs, not 40.

b) Dammit.

 

Sounds like you have air in the line. Brake bleeding sometimes goes really quick, other times the air can really be a nuisance and you just have to keep at it to get it out.

Dave F

 

Yeah, I'm pretty sure the line is completely filled with air. But is that really how it works? I mean, line is full of air, bleeder valve is open, reservoir won't go down?

(disclaimer: i'm asking the question after 6 drinks this evening. yes, i put the wrenches away at 4 o'clock.)

 

Yep.

Remember what I said, about replacing everything at the same time so you don't have to do this more than once?

Filling and bleeding an empty Yamaha hydraulic brake is an exercise in frustration, requiring lots of patience.

A Mity-Vac kit ($30 or less lots of places) helps IMMENSELY in refilling the system, but getting it bled is still a PIA. I would recommend a vacuum or pressure-fill; there are many DIY substitutes if you don't want to invest in a bleeding kit.

Make sure the little fluid port in the bottom of the M/C isn't clogged; and you can "crack" open banjo bolts in succession leading away from the M/C to get fluid to each juncture.

 

I agree these are tough brakes to bleed. I tried to do mine the hard way, but I wasn't making enough progress so I used a vacuum pump and an overflow flask to speed it up. This works great if you have or can get the overflow (need some tubes: 1 long & 1 short, two hole stopper, and bottle or flask) then just use any type of vacuum. Even a hand pump would do the trick. You could also do this w/o the overflow by using a long piece of clear tubing and just don't let the brake fluid make it all the way through before you drain it and go again.



If that's not an option I would try bigfitz's idea of opening the banjo's just a bit and let time and gravity do the work for you. After you get down to the halfway point with fluid, open the bleed screw and put a can under to catch drips and let it drain to there again. It will take a while to work this way (overnight at least) but it should get you to the point that you can bleed normally.

 

Alrighty! So I hate when people post problems, get advice, and never come back to say how they did it, so I'm reposting this from the other thread.

The problem I was having turned out to be the fact that there was SO MUCH AIR in the system that the tiny little piston in the master cylinder wasn't going to be building anywhere enough pressure to pressurize+bleed the system.

So I had to do it piece by piece, and the instructions for that follow.

 

That's great news man. It just goes to show that there is nothing that can't be overcome, especially if you first overcome the notion that it can't be done. Believe and you will...well you get it.

And now after your odyssey you are the 'master bleeder' and in this case that's a good thing.

 

Fitz is there a how to on rebuilding the front brakes? I had my rear brakes redone by the shop that fixed my bike but not the fronts and I am having similar problems as him, but only when pulling the bike backwards.