i have run out of patience

[gaffer77]

hi there it was technical tips on this site for bleeding the brakes under maintanance in my book it shows a c clip holding piston in

[strom]

on the yamaha parts page read tech bulletins. There is some anti-squeal stuff there too...

LP

[beechfront]

fri morning went into the shop that sold me the MC.

mechanic said he has used that same MC on dual brake systems before & it worked, and still thought i had air in there and to come in this morning and he would look at it.

so this morning.... he had no luck either.

he said since it is able to build some pressure that it is not the plunger.

am going to bring it in tomorrow (sunday) and he is going to look at it some more. said if he couldn't get it working that there were a couple other bikes around that he could rob a MC off of to get me going.

so i'll find out tomorrow i guess. he is also beginning to wonder if the piston size is the problem.

[xssiveone]

Hey, that's pretty nice of him. At least he is willing to try and help, not blow you off and tell you the warranty ended when you crossed the threshhold.

Keep us posted on the results, would love to hear the final cure for this.

[Bill__Woods]

Here is my idea.
I have seen this on motorcyclebrakes & hydralic clutches on cars (ie, ford ranger). How far is the piston actually moving in the bore when you squeeze the lever. The factory spec betwwen the lever screw & the piston is 8mm (if my memory serves me, that is). My friend had the same problem on his XS750 after installing new brake pads and flushing the lines. It took us awhile to figure out the Screw on the lever was too far away. Thus the piston was not actually travelling far enough for proper brake operation (not enough pressure).

What not get get a new seal kit for the old Factory Master Cyclinder? They are easy to reseal.
1. Take off the brake handle
2. Pull off rubber bust boot * retaing clip
3. Remove snap ring with snap ring pliers
4. Remove Piston from bore.
5. Remove spring from bore.
6. Clean with Brake Cleaner
7. Clean the "spooge hole" per tech tips on this site
8. Clean Again with Brake Cleaner
9. put New piston from rebuild kit & spring back into the bore, lubed with New Clean Brake Fluid (DOT3).
10. Reinstall dust boot, clip, and lever.
11. fill with brake fluid and bleed master cyclinder with your Finger over the hole, Before installing on bike.
12. Install on bike and bleed 1 side at a time. Do not pull the lever all the way to the bar, pull about 1/2 to 3/4 .

Good Luck!

[fusionking]

So beech what happened??

[beechfront]

well he robbed a MC off of a 750 honda (single disc). Same thing.

he finally agreed with me and told me to just order the one from partsnmore and bring it in when it showed.

partsnmore MC is not going to be here until friday. which means i am going to miss the bozeman rally.

[TopCatGr58]

Hey Beech,

If you still have the other MC, just connect ONE of the front calipers, bleed it thru, that way you will have SOME of the front stopping power, just not ALL of it. Many bikes have only 1 caliper on front! Just put the fluid supply bolt in the other caliper, or just take it off till after the rally!? Just an idea? Hate to see you miss a Rally cause of no front brake!
T.C.

[TheDjost]

Did you check that the caliper pistons are working ok? If the rubber o-rings are not creeping properly you will need to punp the brake lever even with a working m/c and a properly bled system.

-Justin

[beechfront]

justin i've been wondering all along if it isn't something down in the calipers but everyone tells me it has to be the MC.

topcat - that is a great idea... unfortunately last thursday was the first time in several years that i lost my temper. and at that time i happened to be holding a certain motorcycle part.

[beechfront]

and on the 8th day God said "let there be brakes"

and it was so.




Partsnmore master cylinder is GREAT! ordered monday and it's here already. from canada even.



still squishier than I like but brakes are as good or better then they have ever been. i think some new brake lines now would get me back as good as new. but for now they are plenty good.

[randy]

Beechfront,

Have fun at Bozeman. When you're ready for new brake lines, drop me a 'line'

Randy

[prometheus578]

For what it's worth.... which usually isn't much... how are your brake lines? Old rubber brake lines get weak. By this I mean, when you apply the brakes, they expand, and rob some of the pressure. I' ve squeezed levers, and watched as the brake lines moved around. It doesn't take much to steal pressure and give you a spongy feeling. Steel braided cable would be the way to go. What that costs, I don't know. Another trick, as alluded to by a previous post, is to turn the handlebar to the left so that the brake lever points up, squeeze the brake lever and use a zip-tie to hold it back. Leave the bike overnight. This allows any air in the lines to migrate upwards, and out through the master cylinder's bleed hole. I work in a shop... and I HATE bleeding brakes.

[TopCatGr58]

How about a followup on that new MC!?

Hey there Beechfront,

Just wondering about a followup report on your new MC. You had posted in another thread that it seemed to fade a bit, but was still functioning. Have you rebled the lines? Does it still feel about as good as the OEM one? Would be a good thing to cross post in the PRODUCTS REVIEW section as well!?
T.C.

[John]

Phoenix injector system

Anybody ever heard of one of these? I bought one from my Matco dealer a while ago, and it works well. It bleeds any brake/ clutch hydraulic system by attaching to the bleeder screw, and forcing the fluid backwards to the master cylinder. It's a one man job on cars , trucks, and anything else with hydraulic brakes/clutch. Before starting, make sure to protect the finish on the bike. We all know what brake fluid will do to paint. On some of these older bikes, it may be a good idea to remove the brake hose from the master cylinder when first starting to inject. That will allow any accumulated junk in the lines to be purged out. Then pump the master cylinder dry. That will serve two purposes. One, it will empty the reserviour, and two, if there is any trash in the cylinder bore, it will be flushed out. Using new copper crush washers, reconnect the hose to the master. Put the master cylinder cap back on, or leave it on if you didn't remove it. The injector will generate a lot of pressure if you squeeze the handle too hard, so keeping the cap on is important. The reserviour doesn't hold vey much fluid, so check it often to make sure it does not overfill. Now I have not used it on my XS because I haven't needed to yet, but there will come a time. Another good hint to cleaning the system is to purge all fluid out and pump some rubbing alchohol through it. It cleans well, absorbs and carries away any moisture, and dries clean, leaving no residue. This I have done, and it works well.