Hey guys!
Can I replace the original bleed screw with a regular one that's also longer than the original one? longer one?
I'm talking about the M5 4.5mm (Y8RM98010) screw for BL-M4100 levers.
These screws have been problematic from the very beginning. Right now, the screw just keeps spinning endlessly. To check if the threads were still intact, I tried screwing in a longer M5 screw (length 1cm), and to my surprise, everything seems to work fine.
But is this a safe and reliable solution in the long run? I know it doesn’t look great, but I’m looking for an alternative to buying new brake levers since the 4.5mm screws just don’t hold at all and it's not possible to screw them in.
Thanks in advance!
by xenoraki
3 Comments
I mean if it works fine it works, but I’d imagine if the screw was longer the head of the screw wouldn’t compress the o-ring properly? Basically I imagine air will seep in, and your brakes will get mushy and then not work. But if you can tighten it properly a screw is a screw.
The other thing to consider though is if you use a steel screw on an aluminum threaded thing like your levers, and over-torque it the lever will strip and that’s a bigger issue than replacing the screw obviously.
For the bleed screw if I remember correctly you only like 1-2nm of torque, it’s really very little which makes them easy to strip.
Sounds to me like you over-tightened it and stripped the threads; are the threads on the screw gone, or the threads in the lever body?
That particular screw doesn’t need to be super-tight, it just needs to be tight enough to make a good seal with the o-ring so fluid doesn’t leak when you apply the brakes (and therefore hydraulic pressure).
Not an expert in the subject. Personally I’d get a new brake lever. If we were talking about a shift lever, no problem. But if your brakes go out at the wrong time, that can be really bad. I get that they’re fairly new, but one bad crash will negate the extra cost of a new brake lever.
Also keep in mind that the brake system doesn’t just hold fluid, they also need to hold pressure. If air seeps in or fluid can seep out, you won’t get the pressure you want which means you won’t get the braking force you need.
But this is pretty much all speculation on my part. Will they fail? Who knows. Is it a risk you’re willing to take? That’s for you to decide