Soooooo... I have been having issues where I go to start my 1st session of the day and I notice that my brakes are "mushy". Not nice, stiff, & firm like I am used to when I have just finished bleeding the brakes. I still have front brakes, just not as much as I expect or want. If I go for a lap, the brakes warm up, things get firm and I'm late braking w/ no worries. But the warm up lap is a must. I start trouble shooting and I notice that the banjo bolt area is weeping slightly and I begin my investigation. I take my trusty 12mm and I try torquing down a bit on the bolt. Sure enough, the bolt begins to tighten. I must admit, I"m not using a torque wrench, as some of you torque spec nazis out there would. However, I do not wrench down on this bolt like my life depends on it either. After a 1/4 turn, I notice the bolt slips and feels loose again "CRAP"... I have had this Brembo master cylinder since I picked up the bike, w/ it installed, and have never really had any issues with it, nor have I ever touched the banjo bolt. In fact, the only maintenance I have ever performed involving the Brembo is that of bleeding the brakes as needed. Today, trying to investigate my issue further I pulled out the banjo bolt only to find that all the threading inside is stripped out. :-/ Clearly I have woes ahead of me. I have a track weekend ahead of me and I have attempted a temporary fix by using some locktight thread sealant and some High temp lock tight on the very last thread that remains in the master cylinder. After it cures come tomorrow, I will refill the fluid and see if it will hold pressure enough to last me through the weekend. So, I have 2 questions... 1. I don't really see much room for the possibility of using a larger thread/diameter banjo bolt. I know these things are made to fit the hold and to minimize space between the lines and the bolt themselves. Is this a possible fix? Getting a larger diameter on the threaded portion of the banjo bolt and retapping the thread in the master cylinder? Or am I SOL? Any suggestions? 2. If replacement is the only option, then which master cylinder should I be eyeballing as a replacement? I never purchased the original Brembo, as the previous owner took care of that for me (and apparently stripped it out for me too). I am running steel braided brake lines, and the stock tokiko (sp?) calipers. This is for an '05 Kawi 636. I'm looking to get as much stopping power as possible, so should i be going with the largest diameter master cylinder? I'm not even sure which model I have on my bike now. Also, as I have not gone down the route of brake system upgrades before... Are all the lines, and banjo bolts the same diameter? Or do they vary? Is this something I need to consider when purchasing a replacement. I'm hoping to not replace the lines I currently have as there is nothing wrong with them. Also, does a replacement master cylinder come with a new banjo bolt, crush washers, etc? Any and all help is welcome. I am gonna need to act on this quick as I may have to over night a replacement, so please post fast and post a lot. Thanks guys... One last thing, Does Brembo make a master cylinder with a brake light switch? I'm asking as I use this bike for Track & Street purposes and if I need to replace my master cylinder, I figured this might be a good time to make sure I can get a functional brake light for the street. If not, no biggie, I have been running a solid light for a while anyways... lmao... (don't judge me )
Do you think that a heilcoil will let the brake system maintain pressure? I'm not sure that this would work. Wouldn't it allow brake fluid to seep out due to the insert not being sealed into the drilled out hole? BTW, never seen heilcoil before, watched a video and that is bad-A. Gonna have to remember this on future projects... Thanks.
I think it seals against the sealing washer on the face of the M/C... flange? Threads never seal unless gooped with something, IMHO. So use helicoil, it is fine, I think.
I wouldn't remotely trust it with Locktite. On a bolt that wasn't gonna be gooped in a pressurized caustic lubricant, maybe. On a banjo bolt.. no.
That master cylinder is now what we like to call an expensive paper weight. This is why you always back out bolts before going to tighten them any more, because you just never know if it's a crush washer leaking or the bolt actually being loose. You can try using a heli-coil, as that will work far better than loctite (which is useless anyway unless there's threads to lock), but on something that's sole purpose is to stop you, I wouldn't trust it. Don't even think there's really enough room to drill and tap to put a threaded insert in to still use the correct sized banjo bolt.
I can't answer all your questions, but I also don't think I'd trust using loctite, or anything else like that. I think the loctite could get in there and contaminate the brake fluid. Not sure about a larger bolt, not sure there's room for a slightly larger bolt to snug up and seal? Then you'd have to find larger crush washers, too. I'm pretty fussy with front brakes. A failure could cost you a lot of injuries, maybe even your life. Is your life worth trying to fix it, or just replacing it? The Brembo RCS, that adjustable one that you can select from 19x18 and 19x20, has a brake light switch. It comes with a banjo bolt (not all do), but keep in mind that depending on your bike and the type of aftermarket lines, it might be too long. They come with a 30 mm. On my gixxer with Galfer lines, I needed a 28 mm. Brembos use 10x1.0 bolt (many japanese bike masters use 10x1.25). The Brembo tubing diameter from the reservoir to the master is also narrower than stock, so it's a good idea to get the Brembo reservoir if you don't already have it, and "brembo" size tubing. Not all come with the bolt and crush washers, check when/if ordering. The RCS I think does, but the "regular" ones don't. The lines are all pretty much the same. The diameter of the banjo on the end where the bolt goes thru is the same (another reason you can't tap it out and use a larger bolt), however, the thickness (width) between stock and some aftermarkets are different, the aftermarkets (Galfer and Goodrich) are narrower (8 mm wide compared to 10 mm for the stock), see above, which is part of the reason why I needed the 28 mm length bolt, the 30 mm was too long. Just as an fyi, you can get functional brake lights with any of the aftermarket masters by purchasing a banjo bolt that has a pressure switch incorporated into it. Just wire it in and you're good to go. The disadvantage, however, is that it requires quite a bit of pressure to activate, so the light only comes on when you squeeze pretty hard. Light braking won't activate it like it does with the stock mechanical switch.
We have everything and anything that you could possibly need to fix this in stock, and can explain the advantages and/or disadvantages of the several brake master cylinders available. No problem in getting the parts to you in time for the weekend. Call us at 973 386 0040 if you need help.
+1 on having a cool paperweight. Even if the locktight would hold, I wouldn't run it... not on the front brakes of a track bike...
Helicoil, if done right, is more than capable of handling the loads in this system. It will be just as strong as the original threads (actually, it will be slightly stronger due to the increased diameter). There is no locktight or any goop in helicoil repairs. I would have a pro machine shop drill, tap and install your insert, and put it out of my mind.
But, if helicoiled, you'd need a slightly larger banjo bolt, correct? I'm under the impression that they're a standard diameter? If you could even purchase a thicker banjo bolt, it also wouldn't fit in the banjos at the end of the brake lines?
Chuck it. Your brakes are not an area where you could think 'well, this might work'. Strip that sucker for anything that could be useful in the future, but throw away the body.
No, if helicoiled the threads will be restored to original size. The M/C is drilled larger, tapped to the helicoil size, but the inside of the helicoil is the same as the original threads after the coil is inserted. M/C disassembly would be wise, as there will be filings from drilling and tapping.
On Brembo go with Yoyo. Fred is an ex-racer and knows his stuff and knows Brembo. I would not try to save $ on the braking system.
How much you wanna pay for it? I just ordered my new RCS 19. If not it's going up on ebay or parted out on ebay. Thanks guys for the suggestions.
