I’m working with Shimano 105 hydraulic disc. In past experiences installing olives and barbs, the olive would not pass over a barb that has been pushed into the hose, hence the need to slide the olive on first.
I’m running into a situation, however, where my brake hoses (bh90) don’t seem to be expanding enough to stop the olive from passing over the installed barb – it slides on and off even with the barb installed.
I went ahead and decided to try to install the hose anywhere, tightening it into the shifter – of course when I went to bleed my brakes, the brake fluid came out of the insecure connection at the olive/barb. Now, inspecting my shifter, the port where the barb attaches inside the shifter seems to be slightly damaged.
A few questions:
-
Is it normal/okay for the olive to be sliding over the barb? I’m using all bh90 genuine Shimano parts, so I truly don’t understand why this would be happening if it weren’t designed to do so.
-
Am I SOL and needing to replace my shifter now?
Thanks all!
by Rekj16
1 Comment
1. Yes, the olive slides over the barb easily with shimano hydraulics.
2. Put the flare nut on the hose first, then the barb, then the olive. Slide the olive and flare nut up the hose. Push the hose and barb into the caliper/lever all the way until you can’t push it in any more. Then slide the olive and flare nut towards the lever/caliper and start to thread the flare nut in. While pushing the hose into the caliper/lever, use a wrench to tighten the flare nut down. You should have a tight seal from then. The flare nut compresses the olive into the shifter and around the hose and barb to create a water-tight seal. This is why you can’t really re-use hydraulic hoses between two different shimano shifters – when the olive is crushed, it is formed to the shape of the shifter. Despite all of them being made in the same factory, the tiny differences can still cause some leakage.
3. You dont need to replace your shifter. You will need to replace your olive and barb though. You can cut off roughly 5-10mm off the end of the hose and get the compressed olive and barb off of the hose. Hopefully you have a hose that’s a little long for your bike. Once you remove the old olive and barb, reinstall new ones.