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Discussion Starter #1
I have been leaving the bike outside during the bad weather, under canvas and starting it up every couple of weeks

Came to the bike today to discover the rear brakes seized on. After pressing the rear pedal i found the brakes well and truly seized on. The only way to release it is to undo the adjusting nut on the end of the rod and disconnecting the rod.

Then with the aid of brute force i can operate the lever on the drum manually back and forth but with difficulty

So it looks like a stripdown as i have sprayed all the external moving parts with WD40 with no luck, Now heres the problem, i am not good on the spanners but willing to have a go as i have already had an expensive christmas.

I have read the Haynes manual over and over and have come up with the following questions

A) Do i rearly need a torque wrench

b)The book says to raise the FRONT wheel off the ground, by use of a jack, wont that make thing awkward when the rear wheel is removed, Where is it best to position the jack

C)Which part is likely to be seized up inside the drum

D)Do i need to remove the right hand exhaust completely as it mentions the Muffler but i dont know what that is

E)Do i need any gaskets, etc

F) is it best to renew the shoes on replacement and are there any pitfalls which the manual does not mention

Hope you can offer some advise as this remains rather daunting to perform
 

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Vintage bike addict
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If there were no issues with the brakes before storage. I'd get a GOOD penetrating oil like PB Blaster and spray the shaft going into the hub and manualy work the lever until it moves freely again.
 

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Discussion Starter #3
Hi Antig

There were no issues before storage regarding the brakes sticking on, however since i have owned the bike (6 months now) the brake pedal has never been up to much.

The wear indicator is mid range but i rearly had to tread on the pedal before i even started to slow down and due to this only ever used the front brake to stop.

I could virtually stand on the brake pedal and still not stop

I have sprayed and sprayed a release agent on the shaft trying to work the lever by hand but it sure aint giving so it looks like a stripdown
 

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Calif Rider
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Pgchimp this is furgy's write up of how to remove rear wheel. This should answer about any question you may have about how to do it. There are pictures and all the info you need to check your brake, as for what is wrong you will have to pull the wheel and do a good inspection of the the brakes. http://pages.tstar.net/~fergy/writeups/final_drive.html
. If this does not work try typing in Furgy's spline lub.
 

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Vintage bike addict
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If the brake was useless before than I wholeheartedly agree a teardown is in order. Here's hoping a little cleaning and adjustment will put you right.
 

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Linkmeister Supreme
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With time on my hands, I`ve done a little research pgchimp. Weh44`s link to fergy`s link is a good one. It shows how to remove the rear wheel and check and grease the driveshaft and final drive, and put it all back together. I couldn`t easily find a link to the rest of his website, so I searched "rear+brake+replacement" and found 750 Doug`s thread from about 6 months ago. He has some good pics of the brake drum and brake shoe plate assembly and explaination of what was done. I bumped it up, so if you go to the top of this page and click on Quick Links, then on Todays Posts, you will find 750Dougs post with pics, at or near the top of the listings.

Now in answer to your questions, you definately need to pull the rear wheel and find and remedy that brake problem.
Q1. Yes you need a torque wrench. It does not have to be expensive,(I picked up one a few years ago at a discount place for about $20, IIRC). You do want to get a 1/2" drive, micrometer style adjustment, with an audible click, torque reached indicator. The beam type with a scale and a pointer are cheaper to buy, but very awkward to use. Stay away from them. If your sockets are 3/8" drive make sure you have a 3/8" to 1/2" adapter for the torque wrench.

Q2. Don`t lift front wheel. Park with center stand sitting on a piece of 2" lumber, as shown by fergy and 750Doug. This will lift your rear tire high enough to get the rear tire and wheel out without deflating it. Remember to tie the center stand to the front wheel so you don`t roll the bike ahead and off the stand, (also as per fergy`s directions).

Q3. I am guessing, based on your description, that the shoes are probably stuck to the drum. Make sure that you check, clean, adjust and lube all pivot points in the linkage and cable from the pedal all the way back to and including the rear brake camshaft. Ensure that you don`t get any grease on the shoes or internal drum surface.

EDIT.- After re-reading your 1st post a few times, I conclude that antiq rightly identified the problem in the next post as the camshaft, not the brake shoes sticking to the drum per se. The camshaft lever is not releasing and turning back to its "at rest" position. Therefore the camshaft remains in the "brakes applied position." It could be that the shoes are in good condition and all that is needed is a good cleaning and relubrication of the camshaft and brake assembly plate

Q4. You should only need to remove the right muffler and cover which is the rearmost piece on the exhaust pipe. It is about a foot and a half long. Directions and pics are in the Clymer manual. Look at the pipe directly below the right rear passenger footpeg and you will see the connection point. There are 2 bolts below to remove to get the cover off. One more on the clamp holding the muffler to the exhaust pipe , and another just under the footpeg which supports the muffler. That`s it.

Q5. As long as you have the back end this far apart you should check and clean the rear splines and final drive. There are not many gaskets on this bike but there are some O-rings in there that probably should be replaced. You will have to check the pdf file available here or the diagrams and parts list on ronayers.com for part numbers. Seeing that it is a few months before you will be riding, you may want to pull it apart to determine exactly what you need so you can get everthing in one order. Anyone else out there have any advice on this?

Q6. You probably will need new brake shoes, but if you have a space to work in where you can leave the bike partially dismantled, with the parts laid out in order ,and no one will disturb them, see the second to last sentence in the paragraph above.^^^

I hope this helps pgchimp. I`m sure others can fill in anything I have missed or forgotten. I see you have the Haynes manual, not the Clymer that I use, so there are bound to be differences in pics and approach etc. In any event, take the manual, read and mark relevant sections and get a notebook to write notes, question, diagrams, etc. Then take it out to your workspace and review what you need to do while looking at the corresponding area of the bike. Make sure you have all the tools you will need. Have on old towel or blanket laid out on a bench or shelf where you can keep everything in the order it came off, to simplify reassembly later. If you have a Polaroid or a digital camera, take some pics before you start and as you progress to aid in assembly also.

Now is also a good time to check several other things while the rear wheel is already off, such as;

The wiring that runs along a channel in the underside of the rear fender to the rear lights.

The condition, lubrication and adjustment of the pivot bearing for the swingarm, driveshaft assembly.

Condition of the battery and battery box, (need cleaning and/or paint?), all electrical connections under the seat are clean, free of corrosion and sealed with dielectric grease.

Look for any cracks or scratches in the frame that need to be repaired or painted.

Good time to relocate regulator/rectifier if so desired.

Anything else you can think of, or find in the manual, that is easier to get at now, than it will be later when you would rather be riding.

Don`t get overwhelmed or discouraged by this list. Take it one step at a time, at your own pace, and set your own priorities about what needs to be done first. This is just my list of some things I need to check on my scoot. Make your own list and when you get tired or frustrated with the project, stop and take a break. Take it slow and be sure it`s right, rather than rush and have to pull it apart again. Don`t ask how I know this!! Good luck.
 

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Discussion Starter #7
Many thanks for all your comprehensive replys, you have inspired me with confidence to perform both tasks............ Rear shoes and spline lube

However i have downloaded FERGYS 21 pages for reference and just have a couple more points i would like clearing up before i start

A)The Haynes manual says to remove the right muffler and not bother removing the lower shock mounts. Fergy suggests removing both lower shock mounts and no mention of muffler removal.

Is Fergys way better as the connection at the muffler is seized solid and possibly will not seperate from the exhaust. I note that in all of Fergys pics both mufflers remain inplace

B)Fergy says to remove the 4 bolts for the right passenger foot mount to give wiggle room for the right exhaust pipe so you can remove the lower right shock nut I dont understand this sentence????????????????/

C) Finally the manual says QUOTE................................

1)>>>>>>>>>>>>>>>>>>>
2)>>>>>>>>>>>>>>>
3)Remove the rear wheel
4)Remove the Four differential mounting nuts and take the differential off the driveshaft housing (SEE ILLUSTRATION) THe Spring thats installed on the rear end of the driveshaft will come off with the differential

There is no mention of a spring in Fergys breakdown of this split, has he missed it out as i dont need any nasty suprises with a spring flying out never to be seen again

Hope you can clear up these few points

regards
 

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A)The Haynes manual says to remove the right muffler and not bother removing the lower shock mounts. Fergy suggests removing both lower shock mounts and no mention of muffler removal.
I did not remove the muffler, as removing the shocks seemed easier. While I had the shocks off, I changed the shock oils, which was a lot harder job.

B)Fergy says to remove the 4 bolts for the right passenger foot mount to give wiggle room for the right exhaust pipe so you can remove the lower right shock nut I dont understand this sentence????????????????/
Me neither. I had no trouble with the shock nuts. If you don't remove the shocks completely, just loosen the upper nuts and the lower ends should come off easily.

There is no mention of a spring in Fergys breakdown of this split, has he missed it out as i dont need any nasty suprises with a spring flying out never to be seen again.
Yes, there is an important spring, but it won't fly out. Worst case drop on the floor and roll out of sight never to be seen again.
 

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Old Truck Junkie
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I did not remove mufflers either. I removed the lower end of shocks only. I lowered the wheel enough to clear the muffler to remove the axle.
The spring will not fly out. Just note in what order it comes out.
Probably your prob is at the shaft that goes into the brake housing. The one on the right side. You may want to oil the brake peddle pivot also.
 

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Here's some reason's why the steps/techniques vary-

The rear wheel needs to hang low to be removed from under the fender. One way to do this is pull both shock so the swing arm hangs free. I did mine by putting the bikes center stand onto a 3/4" piece of plywood which raises the back end off the ground 1-2 inches, leaving more than enough room for wheel removal. Done this way, only the left shock needs removed as it connects directly to the drive unit. If you're not removing the drive unit, the left shock can stay. Removing the left shock helps make a little more room to install the drive unit if you need to twist it side to side to install, or just remove the lower mount nuts.

The spring inside the drive unit will not "spring out" but as mentioned might fall out and roll away. Spread out a towel under the drive unit and if the spring falls, the towel will keep it from rolling.

The reason for pulling the right hand muffler is the axle bolt. They (usually) go in from right to left, so after you take the nut off, this very long bolt needs to slide out to the right and it needs room to do so; also, can you get tools onto the nut and bolt head with the current exhaust in place? If not, they need removed. I had Jardine pipes on my bike for a while and didn't have to touch the exhaust to pull the rear wheel, so this depends on your setup.

This is why there is differences in the book, and Fergy's write up....

The wheel needs to be high off the ground for removal, downward and out. (high means an inch or two of clearance)

The exhaust gets removed, if needed to access the hardware, and to allow the axle bolt enough room to the right to slide straight out.

Clear as mud? :smiley_th

The first time everybody is about to do this job, they are way more apprehensive than they need to be. It's very easy, and fairly quick, and once you dive in, you'll understand why the written stuff is written like it is.
 

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Oh and one more thing...the rear drum brake on these bikes isn't all that powerful or confident when all the parts are new and everything is working correctly. :drool:
 

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Linkmeister Supreme
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I think you`ve gotten some good practical pointers from others who have actually pulled the rear wheel. Mine is based on reading the manual, posts here, pictures provided and my own general experience in DIY on my autos, etc., but not so much on bikes. Every project I tackle usually has some unforseen problem, such as your muffler clamp bolt that is rusted to the point that it will probably break, if you try to remove it. Even if you do not have to remove it for this maintenance, you will likely need to remove it at some time. In your place I would spray some penetrating oil on it, and let it sit for minutes?...hours?...or days?...while working on something else, and every once in a while,try a wrench on it and if it still doesn`t move, spray a little more. Try a couple of good taps with a punch and hammer on the screw or bolt head, or some heat from a propane torch if the oil doesn`t work. If I`m going to break it, let it be when I have time to fix it, not when I want to be riding. When you eventually put the exhaust back together, use some anti-seize lube on the threads to prevent or minimize at least the reoccurance of the problem, for the next time. I`m sure the Haynes manual has a section where it outlines what shop supplies you will need if you are going to do any amount of maintenance and repairs yourself. Sorry if I`m getting too basic here, but you give the impression that this is at the edge of your comfort zone, mechanically speaking. It won`t take long before you will have accumulated the tools and supplies that you use regularly, and will often be able to improvise something you need.

It sounds like you have started to take a look at least, good luck and keep us posted as to what you find.
 

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Discussion Starter #13
Thanks for the replys especially yours OlHoss, the more i read the more confident i get, and you are right i am at the very edge of my comfort zone and operating as a "One man band"

I have no one i can fall back on with a spanner background if i come unstuck could say i am a "Billy No mates" as far as spannering is concerned.

Went out today and bought the Torque Wrench, checked the sockets and spanners and i have all the necessary ones to do the job, even the 27mm one, dont know where that came from.

However it snowed overnight heavily and as i do not have the comfort of a garage i am not prepared to freeze doing the job, so for now i am spraying all the nuts etc with releasing agent in preperation for the big day

I have just the one final question before i do the job, how much HMP Grease do i need to buy will a 100 gram tube suffice or do i need a tin of the stuff

Thanks again will be back in touch
 

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and the Adventure Cycle
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I have just the one final question before i do the job, how much HMP Grease do i need to buy will a 100 gram tube suffice or do i need a tin of the stuff
I only used a couple spoonfulls or so, so 100 grams will be plenty.
HMP (high melting point) grease should be OK to use, just make sure it has Molybdenum in it.
The grease we suggest (Honda Moly 60 < link to online supplier) has 60% Molybdenum, which is more than most others offer. It is a 85 gram (3 oz) tube.
I would think you could get that on your side of the pond?
 

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Discussion Starter #15
Firstly let me say before i comment on the stripdown that anyone scared of the spanners............... DONT BE.................... There is no one with more intrepidation than me at wrenching but after following this thread plus the other one on the brake strip i tackled the job today with the following results.

After plying the nuts with releasing agent yesterday i got to work with the spanners today, the only prob i had was getting the right hand lower shock mount past the muffler to remove the axel nut,

Won in the end as i used a piece of wood to wiggle the muffler. everything else went as per the printouts now for the results.

can only move the brake lever with great difficulty hence reason for the strip.
on removing the shoes from the drum it looks like it is just the operating lever so i have soaked it in penetrating oil and will possibly strip it out tomorrow.

What suprises me is the everywhere is greased , levers, shoe tips, posts, bearings, gears, diff spline everything looks very healthy, i am well pleased.

As there is a distinct lack of brake dust in the drum it looks as if the drums have not been operating properly.

I cannot rearly afford to replace the shoes as they are unmarked and near new with a lining thickness of 5.1mm

I have looked in the haynes manual for the lining thickness but it only lists the vulcan 800 rear drum brake lining thickness of 4.9 to 5.5mm with a minimum thickness of 2.6mm the vulcan 750 is unspecified

Any ideas on the thickness of the 750????? must be close to that of the 800!!
i would of thought.

Any further advice would be appreciated now i know what caused the brakes not to work

how do i post pics to go with this thread

Regards
 

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Old Truck Junkie
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Use a medium fine sand paper to scuff the shoes a little bit. clean the drum and once you free up the lever you should be okay.
 

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Linkmeister Supreme
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What happened to the post that I made here at noon?? I should have read to the end of the thread before making an edit to a previous post, because you have already found what I suspected with the stiff turning brake cam. Glad to hear that no major parts are needed, just a little time and maintenance.

As long as the brake pads are not contaminated with any grease, I agree with nr, scuff `em up a bit and reinstall.

A couple of more things I thought of to check while the rear wheel is off;

1. Check that both rear wheel bearings inner race turns freely and smoothly.

2. Check the swingarm/driveshaft pivot bearings and pivot shafts for looseness or adjustment needed by alternately pushing it to the left and right. Your Haynes manual should have any other info you need to do this.

I knew you would do just fine with this once you got started. Now you`re on the way to being an experienced wrench yourself, ( or should I say spanner in your case?)

You will have to find someone else to help with posting pics, I don`t know how yet, myself.
 

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Old Truck Junkie
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What happened to the post that I made here at noon?? I should have read to the end of the thread before making an edit to a previous post, because you have already found what I suspected with the stiff turning brake cam. Glad to hear that no major parts are needed, just a little time and maintenance.

As long as the brake pads are not contaminated with any grease, I agree with nr, scuff `em up a bit and reinstall.

A couple of more things I thought of to check while the rear wheel is off;

1. Check that both rear wheel bearings inner race turns freely and smoothly.

2. Check the swingarm/driveshaft pivot bearings and pivot shafts for looseness or adjustment needed by alternately pushing it to the left and right. Your Haynes manual should have any other info you need to do this.

I knew you would do just fine with this once you got started. Now you`re on the way to being an experienced wrench yourself, ( or should I say spanner in your case?)

You will have to find someone else to help with posting pics, I don`t know how yet, myself.
I up load to photobucket and then use the img link or the url. The img link gives a picture, the url gives a link to a picture.
 

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Discussion Starter #19
Thought you might like an update on my progress, however if you think that i am going over the top regarding postings on this subject someone please say so and i'll call it a day.

Stripped the shoes off and undid the lever and pulled the cam from the housing Not before marking everything with TIPPEX IE the lever position in relation to the drum, the lever position in relation to the cam,

Anyway the cam where it goes through the drum was rusted good and proper, so after half hour with the emery cloth cleaning off the cam and the housing there is not a trace of rust to be seen

The part which i was dreading was re assembling the shoes on the cam, but this was by far the easiest thing so far as i just followed the manuals advise and put the springs on the shoes then formed a V with the shoes then easing them slowly eased them over the cams into position, All in all about 2 minutes to perform that task

Put the re assembled drum back into the wheel , worked the lever and its operating brilliantly i am well pleased.

Will put it all back together tomorrow but i need advise again on the following,

A) Do you grease the axle shaft and spacers

B) Do you put grease inside the wheel bearings which appear to be sealed

C) Do you put grease on the cog on the back of the wheel where it meshes with the diff

Thanks again
 

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Old Truck Junkie
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Thought you might like an update on my progress, however if you think that i am going over the top regarding postings on this subject someone please say so and i'll call it a day.

Stripped the shoes off and undid the lever and pulled the cam from the housing Not before marking everything with TIPPEX IE the lever position in relation to the drum, the lever position in relation to the cam,

Anyway the cam where it goes through the drum was rusted good and proper, so after half hour with the emery cloth cleaning off the cam and the housing there is not a trace of rust to be seen

The part which i was dreading was re assembling the shoes on the cam, but this was by far the easiest thing so far as i just followed the manuals advise and put the springs on the shoes then formed a V with the shoes then easing them slowly eased them over the cams into position, All in all about 2 minutes to perform that task

Put the re assembled drum back into the wheel , worked the lever and its operating brilliantly i am well pleased.

Will put it all back together tomorrow but i need advise again on the following,

A) Do you grease the axle shaft and spacers Not needed

B) Do you put grease inside the wheel bearings which appear to be sealed no grease

C) Do you put grease on the cog on the back of the wheel where it meshes with the diff a little bit, don't get messy

Thanks again
If you need help keep asking
 
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