damn brakes

[oldgoat]

ok im going to wait for skydoc to get better then im sending the calipers out for a fresh rebuild. i tried every thing in the book. i bought a mighty vac flushed the system. new DOT 4 . as thats all the store had on the shelf. took it out for a ride today just up and down my back road here after about a mile of back and forth it locked up again this time 5 ft from my front door. so im lucky there. so my opion is calipers need a rebuild?

it must be sticking? sorry to rant here guys and gals too.

i will be comming into some money in december due to a uncle who passed on.

so a new bike might be in order? but this one will remain with me its gotten to be a chalenge and sooner or later one of us is going to give in LOL

[MiCarl]

I'm under the impression that letting fluid out always unlocks them. If I've got that right you don't have a caliper problem.

 

If releasing the bleeder or banjo bolt unlocks them then you either have a master cylinder problem or too little free play in the pedal linkage. Did you check the free play?

[Marcarl]

I'm under the impression that letting fluid out always unlocks them. If I've got that right you don't have a caliper problem.

 

If releasing the bleeder or banjo bolt unlocks them then you either have a master cylinder problem or too little free play in the pedal linkage. Did you check the free play?

All together on that for sure,,,, it's the master, either case.

[Venturous Randy]

Sounds to me like you may have too much fluid in the rear master.

RandyA

[MiCarl]

Sounds to me like you may have too much fluid in the rear master.

RandyA

 

That would be an easy fix. Put it on centerstand, remove fill plug, and any excess should run out.

[1BigDog]

While I also agree on the master cyl needing a rebuild your brake line may also be deteriorating on the inside. Small flaps of rubber will bend in there with the flow and cause your fluid to not return, kinda like a check valve. After sitting for a while the flaps may go back to their old position and then release the brake. This happened on an old VW that I had and it drove me nuts. A VW mechanic suggested I change the rear rubber lines and it worked like a charm. Try adding an SS line on the rear and see what happens. That line is probably the original and its now 26 years old. If you do go ahead with the rear master rebuild, make sure you blow out all the openings with compressed air. There is one teeny orfice in there that can really ruin your efforts if it remains clogged.

[oldgoat]

yep i think the master might be shot to heck?

good old skydock bless his soul got a PM off to me on what to do.

going to give it a shot latter this evening. if that dont work.

he has other options. poor man had back surgery and still took the time to get to my PM

hes tops in my book talked abot replace with a mkll rear master? i just cant understand why good old yahmaha didnt put a darn sight glass on these rear masters?

or some kind of darn dip stick. all right im waiteing for it?

[tsigwing]

ok im going to wait for skydoc to get better then im sending the calipers out for a fresh rebuild. i tried every thing in the book. i bought a mighty vac flushed the system. new DOT 4 . as thats all the store had on the shelf. took it out for a ride today just up and down my back road here after about a mile of back and forth it locked up again this time 5 ft from my front door. so im lucky there. so my opion is calipers need a rebuild?

it must be sticking? sorry to rant here guys and gals too.

i will be comming into some money in december due to a uncle who passed on.

so a new bike might be in order? but this one will remain with me its gotten to be a chalenge and sooner or later one of us is going to give in LOL

 

 

My truck had a similar problem and it was the brake line. Replaced it with a fresh one and problem solved.

[Condor]

I had the same problem on my '83 when I first got it. My rear brake would lock up after a short ride around the block. I rebuilt everything I could get my hands on to no avail. Cost just a few bucks to do it all too. I finally found the problem, and it would have been an easy fix... if I'd knew about it. The hot fluid expansion hole was plugged. On the rear master it's located under the plastic elbow on the side of the master where the reserve hose connects. It can easily be over looked even when rebuilding the master. All it takes is a small piece of crud to get jammed in the hole, and the expanded fluid will start to apply the brakes because the expanded fluid can't return to the reserve...the more the brakes drag the hotter the caliper gets... the hotter the caliper get's the more the fluid applies the brake. It's a vicious downward cycle. Clearing the hole out with a small wire and bleeding the 'H' out of the master takes care of the problem. Take one of those wire ties you can find in supermarket's produce sections and strip the paper off. It fits in the hole. Or..... take a very small drill bit and enlarge the hole, so it has to be a big piece of crud to plug it up.. I don't know why Yamaha didn't do this to begin with.... Locking up the rear brakes, although not very common, happens more than it should. So, save your money and take a trip to the grocery store.

[MiCarl]

..... take a very small drill bit and enlarge the hole, so it has to be a big piece of crud to plug it up.. I don't know why Yamaha didn't do this to begin with....

 

Yamaha (and every other brake builder) made the hole small so it doesn't bleed much fluid when you apply the brakes. Enlarge it and you'll loose braking ability.

 

Need to be careful probing it with a wire so it doesn't get enlarged either. Much better to use compressed air if you can.

[oldgoat]

well im getting down and dirty with this i pulled the master off. noticed the hose was very very soft? also im going to have to take a pic to show you this and figure out how to post it? this master has been fixed kind of welded. by the fill bolt? they did a good job but still?

well i pulled the top cover off and damn!!! PO must have had this bike over in the sand lot? inside was a yellowish looking film? and what felt like grains of sand? i could pull it out like snot!! and the white plunger thing for the brake switch was stuck? im now going to give it a good cleaning. reinstall the new hose i bought re flush out the brake system. forth time has got to do it? but now its miller time and the nephew and niece are going to be here to see and stay with uncle jim. while mom and dad get a little time to them selfs. plus i get cookie and cream ice cream. now where did i put them barney tapes:scratchchin:

[Condor]

Yamaha (and every other brake builder) made the hole small so it doesn't bleed much fluid when you apply the brakes. Enlarge it and you'll loose braking ability.

 

Need to be careful probing it with a wire so it doesn't get enlarged either. Much better to use compressed air if you can.

 

Sorry Carl, I can't agree with you. The only time the expansion hole comes into play is when the master piston is at rest. It has nothing to do with application. It closes off almost imediately when the piston cup is moved forward about 1 or 2mm's. Other manufacturers have larger holes. Honda for one actually puts a baffle in there to keep the initial 'squirt' from blowing fluid out of the reserve with the lid off. I'm not talking about punching out a 1/8" hole, but like I said a very small drill bit. Maybe I should have been more specific and said one of those very small bits that we always seem to break immediately after buying a new set of bits.... BTW, that wire does work.

[Scooter Bob]

well im getting down and dirty with this i pulled the master off. noticed the hose was very very soft? also im going to have to take a pic to show you this and figure out how to post it? this master has been fixed kind of welded. by the fill bolt? they did a good job but still?

well i pulled the top cover off and damn!!! PO must have had this bike over in the sand lot? inside was a yellowish looking film? and what felt like grains of sand? i could pull it out like snot!! and the white plunger thing for the brake switch was stuck? im now going to give it a good cleaning. reinstall the new hose i bought re flush out the brake system. forth time has got to do it? but now its miller time and the nephew and niece are going to be here to see and stay with uncle jim. while mom and dad get a little time to them selfs. plus i get cookie and cream ice cream. now where did i put them barney tapes:scratchchin:

 

Sounds like you're getting close on it now. I've seen that gunk in old brake systems before:think:. Maybe its what happens to old brake fluids that dry out?

 

If this doesn't get it taken care of, help could be on the way. I'm heading east in a few days.

 

If you'll spot me a place to crash :draming:Thursday night and give me a little beer:beersign:, I could take a look at it for you.

 

On second thought, if I go your way, I'll miss chikago completely:cool10:, and that's worth a lot to me, so I'll even bring my own beer.

 

Let me know how it goes, Scooter Bob

[Kirby]

This reminds me of my old truck front brakes. I did everything to try to keep one side from locking up. Finally a guy told me to replace the hose to the brake. He described it just exactly like was said earlier. The worn out hose was acting like a check valve and not letting the oil return. Anyway I did what he said and it fixed the problem. Not saying all this other advice isn't worth listening to, just saying it reminds me of something that happened to me. Good luck with the repairs in any event!!!!

[DragonRider]

Ok, I am having the same problem, I now have my master cylinder off, I have pulled the elbow off. I see 2 holes one is on the bottom of the opening and when I depress the plunger I can see it moving inside, the other hole is above this one, doesnt look like it has a hole all the way through, tried the wire from a twist tie, but wont go in........

[ATTACH]45624[/ATTACH]

 

 

I had the same problem on my '83 when I first got it. My rear brake would lock up after a short ride around the block. I rebuilt everything I could get my hands on to no avail. Cost just a few bucks to do it all too. I finally found the problem, and it would have been an easy fix... if I'd knew about it. The hot fluid expansion hole was plugged. On the rear master it's located under the plastic elbow on the side of the master where the reserve hose connects. It can easily be over looked even when rebuilding the master. All it takes is a small piece of crud to get jammed in the hole, and the expanded fluid will start to apply the brakes because the expanded fluid can't return to the reserve...the more the brakes drag the hotter the caliper gets... the hotter the caliper get's the more the fluid applies the brake. It's a vicious downward cycle. Clearing the hole out with a small wire and bleeding the 'H' out of the master takes care of the problem. Take one of those wire ties you can find in supermarket's produce sections and strip the paper off. It fits in the hole. Or..... take a very small drill bit and enlarge the hole, so it has to be a big piece of crud to plug it up.. I don't know why Yamaha didn't do this to begin with.... Locking up the rear brakes, although not very common, happens more than it should. So, save your money and take a trip to the grocery store.

[Condor]

tried the wire from a twist tie, but wont go in........

[ATTACH]45624[/ATTACH]

 

Are you using a wire from a paper tie, or a plastic coated one? The weaker the tie the better. Try another tie, or a very small needle??. Or..... try blowing it out with compressed air. One of those air guns with the rubber tip might work. If all else fails there's always the mini drill bit. One way or another it needs to be cleaned out...

[DragonRider]

I finally got the wire through, then blew it out with compressed air, and put it all back together, and took it for a test ride, made several panic stops from 80 mph, and everything worked fine, brakes are back to normal, which really isnt all that great on a 1st gen, but at least I wont be stopping to open the bleeder valve everytime I ride it......:banana::banana:

 

Thanks Condor, my faith has been restored, that was well worth $12.00. Next drink or two is on me.

Are you using a wire from a paper tie, or a plastic coated one? The weaker the tie the better. Try another tie, or a very small needle??. Or..... try blowing it out with compressed air. One of those air guns with the rubber tip might work. If all else fails there's always the mini drill bit. One way or another it needs to be cleaned out...

[oldgoat]

aww man do i feel like a fool:bang head: i didnt tear it down far enough:bang head:

just saw the picture on here of the master and what i did was removed the res. cleaned it. reinstalled it then saw the picture of the master on here by the way thanks for posting that pic. dragonrider. now tomorrow i know what more to do. i take it the plunger rod will stay on the lever so just pull slowly to take off master? ok you all can call me names i got it comming to me. but im still going with a master from skydoc. the brake hose from dinngy. and do it right. look im new to this type of brake system but i think im going to get it done right in a week or so.

[sgn]

That said an Oldgoat couldn't learn a new trick?

 

Stay with it, like I told you on the phone - just keep trying - everything you do is just another lesson.

 

If your not learning your dying !

 

Steve

[Condor]

I finally got the wire through, then blew it out with compressed air, and put it all back together, and took it for a test ride, made several panic stops from 80 mph, and everything worked fine, brakes are back to normal, which really isnt all that great on a 1st gen, but at least I wont be stopping to open the bleeder valve everytime I ride it......:banana::banana:

 

Thanks Condor, my faith has been restored, that was well worth $12.00. Next drink or two is on me.

 

Glad it worked and you're deciding to keep the bike now Lewis.... I can't take all the credit, Klaus (kbert777) came up with the wire tie trick. Before that I used a very small needle ....shhhh don't tell the wife.... and compressed air.

[oldgoat]

well i got the master off and i mean the master this time:big-grin-emoticon:

im trying to figure out how to post the pictures here i can put them on my profile in my album. but let me tell ya what i found can you say rust and more rust? the hole is pluged with rust... under the rubber boot where plunger goes in full of rust if i pull that big c clip will the tube come out of the master?i should say when i pulled this i noticed the master was holding the brake in the engaged position so when i was useing the brakes it must have been slowly holding the brake from returning? therefore making brakes start to drag then overheat the brake fluid and wham lock up. and yes an old goat can learn new tricks many thanks to all of you. as i now have a good idea whats wrong. im thinking wait for skydocks rebuilt master he will send me off a mkII. i could clean this but like i said full of rust and is it worth going through the troubble of putting it back on no mater how hard i clean it. im sure more rust will get through.

[Scooter Bob]

im trying to figure out how to post the pictures here i can put them on my profile in my album. QUOTE]

 

To put a pic on a "reply" to this thread, scroll down a little farther to the "additional options" section, click on the "manage attachments" button. You will get a new screen, click on browse, and find the pic on your puter and select it, then click "upload files"

 

When done, it can take a while depending on your connection, it will put the pic at the bottom of your reply.

 

Good luck on the job, Scooter Bob

[oldgoat]

as you can see in the pics this master is full of rust a friend cleaned it up and we installed it for crap and gigles and filled the res. and now it wont pump fluid to the calipers ? system must be full of air. and wont push fluid? so it must need the might vac back on it and draw the fluids. but hey i took it for a short burst down the road i have no brakes but the independent one on the front. but no lock up after a half mile?? but then again if they aint working they shouldnt lock up? i got niece and nephew day at 1:00 so time to stop clean up and put the cover on it or they will try to climb on it. the boy can be a hand full. the niece. just wants cookies and turn on the dvd player and you never see her again unless its time for a new movie. LOL they promised to help wash the bike when im done. wonder how much:mo money: there old enough to know that coins are not as good as that green stuff. now the rest of you here why you not riding??

[gidzhome]

all good posts here. I had two hoses on the front of my F150 do the bicuspid thing too - replacing them cured the pronlem. Never bend the hoses WAY out of position, or let the weight of the caliper hang on the hose.