Help with where to start.....

On your front brake master cylinder using one with a smaller piston size greatly improves braking. One of 10 or 11 mm works vey well. Shop Ebay for one from a Yamaha XT200 I think it is, They made two similar bikes one a 200, one a 225. One had fat tires front and rear the other regular tires. They used a smaller M/C that works well.
Replacing the very old stock rubber lines with either new rubber or better yet braided stainless steel lines is a very good upgrade.
Taking the caliper apart and cleaning it out is a good idea too. As brake fluid ages it gets thin and gets behind the o-ring and binds the piston. A bit of searching on here will find a lot of advice on how to do this.
Leo
 
My front brake gave me fits ! at first it was locked to the wheel the calaper brake pads had swelled from sitting do long.... I had to pull the calaper to get the bike to just roll on its wheels.... the back brake on my bike was the same swollen shoes but all I had to do was back off the adjusting nut a few turns and it freed up.... getting that front brake to work properly was a trial in paitiance.... it would not pump up.... I drained out the Brake fluid and replaced it wirh 30wt oil just so I didn't have to play in brake fluid and it seamed to help quite a bit.... the bottom caliper was seazed it wouldn't move at all when I started.... after soaking it in oil and getting the old brake fluid out I finally got the piston to move in ward and the thing started moving like it should at that point.... though without the MC working I really couldn't tell..... I tried taking the MC apart but gave up as I could not see a way of getting that beastie apart ! .... after some help here and pointing to the tech section I found out how it opened up.... and got it apart....
I cleaned everything up and re assembled it and put fluid in it but it would not pump up no matter what I did
I think it was 2M or gggGary that said with the line off the calaper that the fluid from the resivore on the handle bar should be leaking out slowly...
mine did not do that.... so I took it apart again and totallt disimenbled it a 2nd time.... there is supposed to be 2 holes in the bottom of the
resivour bowl for the brake fluid... mine had 1...the other was a indent that did not go all the way through....
so I took my smallest drill bit and drilled the indent all the way through into the cylinder...like it was supposed to be in the first place.
put it all back together and tried it... still no pumping up...... I got the idea that it was trapped air causing the problem so I put the master cylinder on the ground with the calaper Higher than it.... and tried to make it a straight shot for the air to go up and out toward the bleader on the calaper...
pumping it periodically when it was low seamed to do the trick as I started to feel it was starting to compress the fluid.... I hung the MC back on the handle bar and noticed with the brake line off the calaper it was indeed leaking now I pumped it a few times and it lost what it had.....
I put the line back in the calaper and figured with it leaking like that it would soon fill the line so the only place left for air to hide was at the brakeline connection at the MC..... I pumped it for about 2 minutes with what seamed like no results and then cracked the Line connection to the MC and I got a bunch of air out of it ! I thought AHHH HAAA !!!! i found it..... pumped it for about 2 more minutes and started to feel a tiny bit of pressure building up in the handle ...I cracked the Line bolt again and this time got air and fluid..... I started pumpint it again and it started pumping up like it should and I then started bleading it at the Calaper at the bottom..... it took probably 8 or 9 of these to get the thing Pumped up.... and no more air in the line ... I tightened all the connections and topped off the resivour which I had been keeping a close eye on all this time and I figured I could now at least get the piston Out of the calaper to do repair..... but I didn't need to to my complete suprise the calaper was now working perfectly ! it would stop the wheel and release it when I let off the brake lever .... something I did not expect with it being stuck as hard as it was !
..... Now ...No doubt if you go into these things you SHOULD rebuild them with fresh booties ,seals o-rings and what not....I just wanted to get the darn thing to work and I didn't have money for parts.... so I just re used the old rubber.... Not the wisest idea but it did work for me....
upon testing the front brake I indeed will lock up the front wheel, and release it. as well as there are no leaks anywhere.....
I got extreamily lucky with no leaks !!!!!!!
how the front brake evere worked without that hole through into the cylinder on the MC , is a complete UNKNOWN ! but it did !
...the plastic Bowl/resivour for the brake fluid will pry off if your real careful .... just pry up one side about 1/16" and then wedgge it with a screw driver and go to the back side and wedge it up..... keep working it like that and eventually you can pull it off with your hand.
.....
Good luck
Bob..........
 
Wow that was a marathon Bob, good work getting those brakes done mate. What we did in the shop was use a grease gun to force the pistons out. Drained the brake fluid out, then installed a zirk (we say nipple but I think you guys call them zirks) into the inlet side, then pump the bastard. If that didn't, or wasn't successful, heat the area around the piston and pump it again. Have to be careful when it lets go that you don't wear hot grease. This works, I've done it many times with lots of different brake callipers that were seized....
 
Yea with the condition of the boot on the seized brake piston I was just going to buy a new/used set up, purchase a rebuild kit for it and use mine for spare parts. I have ran down the lines and they are surprisingly in great shape. I actually have a small fluid pump I built and it can send quite a bit of pressure, so I took each line off individually and tested its seal. Seems to all be in tip top shape, it's just the MC piston that's seized up front.

.... Amother update... I just got my parts in from Mikesxs yesterday so I officially have all new dash bulbs now. Also, instead of spending the money to buy the Manual petcock right away, I picked up an online fuel filter and a fuel line quick disconnect from mikesxs. Essentially for temporary fix right now I have created a manual fuel draw Post Petcock. Since he vacuum and everything else is acting up and still pouring fuel into the carbs when the bike is off, I can use that disconnect whenever I am not riding it, then a quick snap together and she's ready to go again
 
Yah ! Sorry all I do get carried away sometimes....but writing means making it easy to understand its not a case of the fewer the words the better it's weather it is easy to understand or not .... at least that's my thinking LOL
....I was going to do that Mick ...I read about that trick here on the forum ...but my greese gun was bone dry ! so I had to come up with something else
as it was the 30wt oil seamed to loosen everything up and in all honnesty I think it would make a far better brake fluid than brake fluid ! LOL
but I did drain it all out and clean it with carb cleaner.... and then put in real brake fluid....
what got me was that the thing came from the factory without a 2nd hole in the MC..... that is dumbfounding ! How did it work for all those years ?
thats mind boggling ! it shouldn't have worked at all, ever.... but some how they got the thing to work at the factory !
its weird !!!
LOL
....Bob......
Edit:
Hay JR..... pull the brake lever off and see if you can wiggle the piston a bit and get it to move the bolt that adjusts to strike the piston end has been known to push it off to one side and that may just be Jambed !!!!! cocked in there a bit sideways... extend the adjustment bolt out a bit and try it !
(after freeing it up).....
Bob........
 
Hay Mick Have you started your xs650 sense the Cyclone hit ? there's probably water all through it ! like being dumped in the lake !
you may have a heck of a time getting it to run again.... drain the bowls and hope your gas-cap sealed real good ! HAHAHAHA!
.....
Bob........
 
So... with some more investigation and deeper digging on my carb/fuel spill problem, I found the issues. Apparently the PO had done a float test on all 4 floats he had at once, and marked the 2 that were leaking. Turns out he mixed 1 up, because I got the float off and tested them on my carbs and 1 was leaking, I tested both of the "bad ones" on the spare carbs, and only 1 leaked, not to mention, I finally got the floats off to clean out that jet and discovered another big issue, which could explain both the left cylinder not firing right away AND the flooding carbs issue. I included a picture and got it all cleaned. Now just to rebuild and remount and give her hell... Thanks! Here's the update!!
IMG_0496.JPG
IMG_0497.JPG
 
INDEED Pete ! this is where a can of carb cleaner with a nozzle or compressed air come in at ....
blast it good !
Bob.........
edit.... don't forget to clean the passage in the float bowl TOO !!!!!
 
Yea... I got her cleaned out really really well, not a smudge on her now.. the only issue is that I didn't consider that the right and left Carbs were different until I reassembled... I knew it, but apparently it didn't chime into my head until I tried to put the 2 I rebuilt together and the fuel ports didn't match up.. Considering both of the bodied for my 2 left carbs are not cooperating with some removals and stuck bolts, I just decided to convert 1 of my rights to a left... I hope this works like I think it will. I have drilled the port for the fuel into the float hole, from the side, and plugged the original side with the port completely. looking down into the float seat hole, they look identical left to right so as long as the left side is plugged well enough this should work out fine. I will find out this afternoon whether or not shes going to fill right and whether or not I have solved all my problems or just need to buy all new carbs.. Next step is some POD filters... Going to look for some on here instead of fleabay. Talk to you guys soon!
 
There ya go JR use what ya have on hand first if possable..... I'm rootin' fer ya to get her going
good luck to ya !
....
Bob..........
 
How ya doing JR ? did that carb mod work for ya ? I never tried that myself, but it should work.... I would think long as you cleaned it really good after word... LOL let us know what you discover please !!!!
....
Bob...........
 
Seems to have worked... I only started her up for a few minutes just to see if she would do it without spewing fuel everywhere and it looks good. No leaks so far and as far as I can tell the fuel isn't backing up into the air intake either, and both cylinders got hot right away, so I'm pretty hopeful that this was the big fix after all. Shes plated, insured, and ready to go otherwise. I'll send some more details with pictures later this evening.
 
Fantastic ! Well done ! don't forget to do a plug color test after a mile or two.... just to be on the safe side ! if it's White don't ride it !
......they should be brown....... not black or white
Bob............
 
Still a bit of fine tuning left to do with the Carbs, the throttle/Idle is a bit off, but other than that she is purring like a kitten. A bit spastic at times, but I sense that is the fuel/air mixture setting combined with the throttle screw. Here are a couple more pictures with the updated grab bar behind the seat... Little by little I am dressing her up. Thanks Everyone!!! More to come!!!
Bike 2.jpeg
Bike 4.JPG
Bike.jpeg
Bike 6.JPG
 

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