- Brakes…. 3 months of standstill: soft & squealy
Both we and the GF’s bikes have been hung since November, because: snow.
The snow had relented and we’ve had nice sunny weather and mid-high teens temp wise. Have been thinking I might head to Lago di Garda on the weekend for a few days. I really want to get back in the bike. The crazy snow here in Bavaria and work has put a stop to that in the last month.
Took my bike from the wall and ride around the block. Very squealy brakes with zero power. Took the GF’s bike down and exactly the same thing. Both XT four pots.
Is it a case of one decent downhill and build up some heat or replace the pad….?Posted 6 months ago
Not heard of the 4 pot caliper seals leaking on forums so far – thought it was just the 2 pots. I’d try and get some heat into the brakes with a few hard stops and see if that helps. If not I’d check over the callipers really thoroughly to see if there are any leaks. If you can’t see any I’d clean the rotors and throw in some new pads and see what happens.
If that fails then I’d change brand of brakes.Posted 6 months agoDaffySubscriber
This is what I’ve found with all of my Shimano brakes. If the bike is left standing for long periods, the calliper seals seem to leak. My commuter which also has Shimano discs (R785 +M9020 callipers) , had been absolutely fine for 4 years, but the m9020 brakes on all 3 of the MTB went funny in the same period.Posted 6 months agostevemuzzyMember
If hung vertically, the front caliper is at the top of the brake system, so any trapped air which might.have been in the master cylinder will now be at the caliper. I hang all my bikes vertically and have soft lever syndrome on ones that dont get used. Easiest way to fix is a quick lever bleed using the shimano pot thing, however just pumping the brakes a few times fixes it most days as any trapped air returns to the lever.Posted 6 months agodevashMember
Never heard of XT four pots doing this but the 2 pots (M8000) will leak very slightly at the caliper if left idle for a number of months. I wouldn’t be surprised if the 4 pots have a similar problem as its all the same technology.
Mine are always a bit squeaky for the first couple of miles if I haven’t ridden my bike for a while but clear up after building up some heat. I also find that removing the brake pads and giving them a good sand down with some large grit size sandpaper / wet and dry paper once in a while really helps to restore initial bite without having to replace the whole pads.Posted 6 months ago
Sorry…. Should explain.
Bikes are hung on the wall, but horizontally.
When I say soft, I don’t mean the lever is soft, but rather there’s no power. Roll the bike through the flat and the brakes and bite point fell fine. Jump on it outside and no power and lots of squealing.Posted 6 months agolardmanMember
leaky caliper seals. They’re SHimano, they do that unfortunately.
As post above mentioned, it wont happen on a bike you use every day.
If the brakes are less than 2yrs old, they’ll replace them.
I now view my Shimano brakes as 2 year lifespan disposable item. In fact, i send them back to SHimano just before the 2yr mark, even if they don’t squeak (although i say that they do) and they replace them.Posted 6 months ago
Not great if you have to do that with Shimano brakes. Yet people keep buying them – I don’t get it. I had one set of deores that each time you started riding you needed 3 or 4 good sustained braking periods to lose the squeak and lack of power – I moved them on and replaced them with Guides. No such problems since – even if I don’t use one of my bikes for a month or so.
I do have Shimano discs on my road bike (they came with them) but as that’s in use several days a week I haven’t had any dramas with those yet (about a year in to having the bike). So far they’re just relentlessly reliable and powerful. I don’t actually like the sti’s much so if the brakes go faulty outside of warranty I’m tempted to swap the whole lot to Sram double tap and brakes.Posted 6 months agorickonSubscriber
Before escalating to the worst case scenario of blown seals, either give the pads a quick rub down with some sand paper – then go for a ride where you can safely brake on a descent to build some heat, and apply the brakes for a hard stop, do that about 5 times. The pads could easily be glazed and just need bedding in again.
If that doesn’t work… pop some new pads in and see how that goes.Posted 6 months ago
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