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Nice, now go ride this thing
Hard to do with out a clutch handle LOLIm waiting for one from Mikes
Yeah I know just arrived earlier today havent had the time to put it on yet.
Start with post 54 or so, Dave put in his 10 cents worth, Well worth the read, then read the rest of the post to this one. All the chats about Mud? that is re-occurring. There is a reason for that. Brake fluid is (forgive me if I get the word wrong) (okay I forgot the word) Brake fluid will dehydrate. and it will take moisture from the air, and screw up the consistency you need for DOT3 fluid. After 10 years, my wife's bike experience, the master cylinder was a cake powder in the plastic tank. I used a putty knife to clean that out. Then the actuator was equally bad. Once you get the piston out, you can clean the cake or Mud, what ever you prefer to call it. with the exception of the bleeder screw channel, but spray cleaner can get in there. (as well as your eyes)
The cable I just though it out. You can't spray brake fluid down the tube, cause the tube is rubber, and the air pressure wasn't helping, so I upgraded to braided chrome, and I got mine too long.
The cable I just though it out. You can't spray brake fluid down the tube, cause the tube is rubber, and the air pressure wasn't helping, so I upgraded to braided chrome, and I got mine too long.
Thanks for the reply. I have read the whole thread. I didn't see where it specifically said what scorpio did to fix his problem.
I have taken apart and cleaned out both the MC and caliper.
-caliper was rebuilt and a new SS piston was used.
-MC was taken apart and cleaned and rebuilt using a generic kit
-I got a custom brake line made in SS this morning
I tried using both a new aftermarket generic MC and the original one rebuilt with a generic kit.
Still not getting pressure in the handle. The caliper piston is pushing and retracting back.
I'm getting fluid through the caliper bleed screw. I also disconnected the line from the caliper and stuck the end in the reservoir and essentially did a bench bleed on the eBay MC. Then I hooked it back to the caliper and bleed it. Didn't see any more air bubbles, but there is still next to no resistance in the handle.
I am unsure what to do. I may just buy an OEM rebuild kit and use the original MC since I am thinking that the eBay MC may not be pushing enough fluid or something. However I would prefer not to since the MC rebuild from the dealer is like $60.
I am seriously out of ideas and super frustrated at this damn bike.
I have taken apart and cleaned out both the MC and caliper.
-caliper was rebuilt and a new SS piston was used.
-MC was taken apart and cleaned and rebuilt using a generic kit
-I got a custom brake line made in SS this morning
I tried using both a new aftermarket generic MC and the original one rebuilt with a generic kit.
Still not getting pressure in the handle. The caliper piston is pushing and retracting back.
I'm getting fluid through the caliper bleed screw. I also disconnected the line from the caliper and stuck the end in the reservoir and essentially did a bench bleed on the eBay MC. Then I hooked it back to the caliper and bleed it. Didn't see any more air bubbles, but there is still next to no resistance in the handle.
I am unsure what to do. I may just buy an OEM rebuild kit and use the original MC since I am thinking that the eBay MC may not be pushing enough fluid or something. However I would prefer not to since the MC rebuild from the dealer is like $60.
I am seriously out of ideas and super frustrated at this damn bike.
Builtin_DaShed
XS400 Enthusiast
Have a look at the bleed screw orifice in the caliper, spacifically the mating seat where the end of the bleed screw contacts the bottom of orifice in caliper, it may be damaged from over tightening. There doesn't seem to be a lot of material there causing the aluminum seat to distort from over tightening the steel bleed screw.
When I got my bike PO said the front caliper was cracked, after inspecting the caliper I couldn't find any exterior cracks?. I replaced the siezed MC and proceeded to bleed brakes and was unable to build decent hydraulic pressure.
So after some more inspecting I noticed the bleed screw while under pressure was allowing fluid to pass when seated, removed the bleedscrew and the seat in the caliper was squished out of shape not allowing them to seal completely.
Now to find a replacement caliper or come up with a method of repair
When I got my bike PO said the front caliper was cracked, after inspecting the caliper I couldn't find any exterior cracks?. I replaced the siezed MC and proceeded to bleed brakes and was unable to build decent hydraulic pressure.
So after some more inspecting I noticed the bleed screw while under pressure was allowing fluid to pass when seated, removed the bleedscrew and the seat in the caliper was squished out of shape not allowing them to seal completely.
Now to find a replacement caliper
or come up with a method of repairInteresting. I did clean up the end of the bleeder with some sandpaper since it was really rusty and the caliper threads are kinda messed up. When the bleeder is closed, I don't see any fluid leaking past, but when I hook up a vacuum bleeder, I can pull air and some fluid from the bleeder even though it's closed. When I open the bleeder with the vacuum attached, I noticed that the fluid was very foamy. Then I tried putting some grease on the threads and that seemed to stop the foaming. There might be some sort of leak past the threads introducing air?
Not really sure what to do. I was thinking of maybe using a helicoil to fix the caliper threads, and cleaning up the sealing surface on the caliper.
Not really sure what to do. I was thinking of maybe using a helicoil to fix the caliper threads, and cleaning up the sealing surface on the caliper.
Builtin_DaShed
XS400 Enthusiast
Ya, I suspect that you have a similar issue to mine.
I'm not really familiar with vacuum bleeders but it is either introducing air back into the system or is sucking air in from elsewhere causing the fluid to foam.
Since you get fluid past the bleed screw when closed the seat in the caliper is dirty or shot, inspect it making sure it is clean and the same shape as the bleed screws taperd end, it's not the threads that seal but the screws tapered end and the seat in the caliper but I'm sure your aware of this
.
if the seat is shot you'll have to replace the caliper. I'm not aware of a way to repair this as of yet.
Maybe (if the seat in the caliper looks good)
- replace the bleed screw, if it was corroded it could be pitted etc. not allowing a seal.
- crush washers at the brake line/ banjo bolts, are they there, did you replace them, are they in good condition? just a thought.
As for the helicoil to fix the caliper threads that's your call, I'm sure it would work but if it fails the brake is an essential system to go out.
Was back bleeding with a large syringe or a suction tube(gun) covered already in this thread ? that's the easiest way.
I know Drewpy and a few have replaced thier calipers with ones from an R6/ R1 and an applicable rotor, maybe we the XS400 community could find someone to machine us the applicable components for this upgrade and sell them as a kit, I'd sure be interested in one.( might start a thread about this to see if theres any interest)
let us know if you find a solution.
I'm not really familiar with vacuum bleeders but it is either introducing air back into the system or is sucking air in from elsewhere causing the fluid to foam.
Since you get fluid past the bleed screw when closed the seat in the caliper is dirty or shot, inspect it making sure it is clean and the same shape as the bleed screws taperd end, it's not the threads that seal but the screws tapered end and the seat in the caliper but I'm sure your aware of this
. if the seat is shot you'll have to replace the caliper. I'm not aware of a way to repair this as of yet.
Maybe (if the seat in the caliper looks good)
- replace the bleed screw, if it was corroded it could be pitted etc. not allowing a seal.
- crush washers at the brake line/ banjo bolts, are they there, did you replace them, are they in good condition? just a thought.
As for the helicoil to fix the caliper threads that's your call, I'm sure it would work but if it fails the brake is an essential system to go out.
Was back bleeding with a large syringe or a suction tube(gun) covered already in this thread ? that's the easiest way.
I know Drewpy and a few have replaced thier calipers with ones from an R6/ R1 and an applicable rotor, maybe we the XS400 community could find someone to machine us the applicable components for this upgrade and sell them as a kit, I'd sure be interested in one.( might start a thread about this to see if theres any interest)
let us know if you find a solution.
I could remember the g part. 
Ya, I suspect that you have a similar issue to mine.
I'm not really familiar with vacuum bleeders but it is either introducing air back into the system or is sucking air in from elsewhere causing the fluid to foam.
Since you get fluid past the bleed screw when closed the seat in the caliper is dirty or shot, inspect it making sure it is clean and the same shape as the bleed screws taperd end, it's not the threads that seal but the screws tapered end and the seat in the caliper but I'm sure your aware of this
if the seat is shot you'll have to replace the caliper. I'm not aware of a way to repair this as of yet.
Maybe (if the seat in the caliper looks good)
- replace the bleed screw, if it was corroded it could be pitted etc. not allowing a seal.
- crush washers at the brake line/ banjo bolts, are they there, did you replace them, are they in good condition? just a thought.
As for the helicoil to fix the caliper threads that's your call, I'm sure it would work but if it fails the brake is an essential system to go out.
Was back bleeding with a large syringe or a suction tube(gun) covered already in this thread ? that's the easiest way.
I know Drewpy and a few have replaced thier calipers with ones from an R6/ R1 and an applicable rotor, maybe we the XS400 community could find someone to machine us the applicable components for this upgrade and sell them as a kit, I'd sure be interested in one.( might start a thread about this to see if theres any interest)
let us know if you find a solution.
I inspected and cleaned the seat in the caliper. It looked okay. I may just replace the bleed screw with a speed bleeder for convenience sake. Does anyone happen the know the thread dimensions for the bleeder?
The crush washers are new. The master cylinder is a universal eBay unit I found. The brake line is a new stainless braided one.
I didn't do any back bleeding but I did stick the end of the brake line that goes to the caliper into the master cylinder reservoir and bleed the air out that way and then hooked it up to the caliper. Still had a mushy handle after a full bleed.
Haven't really had time to look at it lately, but I'm still confused as to what the issue is. I was thinking that maybe the eBay cylinder isn't moving enough fluid and creating a mushy handle?
Here are the bleeder screws I was looking at getting, Amazon prime FTW!
https://www.amazon.com/dp/B000CPIJOC/ref=cm_sw_r_awd_Iea-tb0VZ4SEM
It says the thread is a M10x1.5. Looks right. Just not totally sure.
Turns out the issue was my master cylinder. Stopped by my local u pull it today and they had a Suzuki there that had a MC that still had relatively fresh fluid fluid in it and the handle had good pressure. Stuck that onto my bike, bled the system, now I have brakes! Woohoo
It's good to have brakes
It really is! Haha. Now I just have to figure out my charging issue... ugh
XSLeo
XS400 Junkie
Most auto parts stores have kits to repair bleeder screws.
The kit has a brass insert that holds the bleeder and has a seat for the bleeder to seal on. You drill out and thread the old bleeder hole so the brass insert threads in.
I think they are somewhere around $10 each.
Around here Advanced Auto has the right on the rack next to the other brake parts.
Leo
The kit has a brass insert that holds the bleeder and has a seat for the bleeder to seal on. You drill out and thread the old bleeder hole so the brass insert threads in.
I think they are somewhere around $10 each.
Around here Advanced Auto has the right on the rack next to the other brake parts.
Leo
