rear Bleed nipple screw leaking

[2007Z6ALL-LED]

I bled the rear brake a little while last month and recently found it has little as a little leak...I unscrewed the nipple and tried to seat it properly and screwed it in again but can't eliminate that little drop come out from the other side on the nipple screw..

May be I need to re-seat it again lean toward to that side and screw it in again?

Anyone has any hint on this? new nipple screw fixed then what size?

Thanks a bunch!

 

[Motogiro]

First if you unscrew that bleeder with out brake fluid pressure you may have introduced air into your brake line line. In any case if you have a leak there you still have risked introducing air/moisture into your brake line and need to bleed it anyway. Unscrew the bleeder and inspect the hole and the bleeder valve mating surfaces for debris, scoring or pitting. Replace if its pitted or scored and hopefully there is no damage to the caliper.

 

[2007Z6ALL-LED]

yeah, that's what I hoped...I unscrewed the nipple screw, bled and re-seated the screw last 2 hr but there's been a little seep out on the other side..I will bleed it again and inspect and re-seat it to make sure it mate properly with the caliper.. (I inspected the screw thread and caliper thread, they both looks fine, no damaged thread...)

any hints, replies will be greatly appreciated!

 

[motojoe122]

I had the same issue the last time I flushed my brakes. In my case it took a couple brake bleeding sessions to clean out whatever was causing the weeping. I removed the nipple and cleaned it too. At the same time, it very well may have been residual fluid caught in the threads that would work it's way up and out with the vibration of riding the bike

 

[FinalImpact]

Twist it in firmly about 3 times. Blast with brake cleaner and then bring the brakes up to full pressure and check.

I seat all hardware like these 2 to 3 times. Same with new brass washers, banjo fittings....

Good luck.

 

[2007Z6ALL-LED]

Thanks for the tip!, confirmed, no leak at all around the thread of the screw & caliper contact after numerous pressure braking ...

I will ride tomorrow and will check again afterward to see any oil residual at all..

Does anyone know what thread size of this nipple screw? 8mm? or 10mm?

thx,

 

[Motogiro]

Thanks for the tip!, confirmed, no leak at all around the thread of the screw & caliper contact after numerous pressure braking ...

I will ride tomorrow and will check again afterward to see any oil residual at all..

Does anyone know what thread size of this nipple screw? 8mm? or 10mm?

thx,

Thread size will also be accompanied with thread pitch.
Specbolt Fasteners Technical Info...learn about motorcycle bolts

Probably any bleeder from a metric caliper would fit.
Correction.
A front bleed screw is $7.45 from Ron Ayers. FRONT BRAKE CALIPER
A rear Bleed screw is $6.30 REAR BRAKE CALIPER
Here's the part number front caliper 15B W0048-00-00 Both S1 and S2 are the same part number
Rear caliper 36Y-W0048-00-00

 

[2007Z6ALL-LED]

UPDATES:
Yesterday, I unscrewed the nipple screw, cleaned it with the dust-buster airbursh (those PC air dust-buster can), and screwed it back in firmly (of course re-bleeding was done again too)

My trip to work today hasn't shown any oil fluid leak at all..well I already order the OEM yamaha nipple screw one rear and one front just in case..

they are ridiculously expensive, cost shipped total of $11.50/each nipple screw - can you believe it? mann!

Thx,
j

 

[2007Z6ALL-LED]

UPDATE: rear Bleed nipple screw leaking

I found out one of the front nipple screw being leaked..a few sip-leaking...it's not that bad. I ordered and replaced that nipple screw..all good.

Can you believe it...the front one which I replaced,,,when I blew the air,,,it's something stuck inside the screw...I didn't bother to clear it and just threw it away....

 

[2007Z6ALL-LED]

Updates: The front nipple screw was replaced and now has no more sip-leak in the screw thread. For the rear nipple screw, I re-seated firmly and also has no more leak (although I bought the brand new rear nipple screw but didn't use it yet).