Specialized Como 3 - Rear brake doesn't work anymore.

Palmthree

Member
Region
Europe
Hello,

My rear brake lever is all loose and the brake no longer works.
They're disc brakes and I seem to have had a leak (it was working fine this morning, but when I went to pick it up for lunch, I noticed this...)...

I can use the front brake for now, but I have to pick up my son from school tonight... How can I fix this? :(

Thanks...!
 
Piecing together the situation from your minimal details, it seems like your rear brake is a hydraulic disc and the hose is broken and leaking. How to fix it depends on the brand. If there's enough slack, you may be able to shorten the existing hose and reattach the fittings. If not, you'll need a new hose. No matter what, the brake will need to be refilled and bled.
 
Piecing together the situation from your minimal details, it seems like your rear brake is a hydraulic disc and the hose is broken and leaking. How to fix it depends on the brand. If there's enough slack, you may be able to shorten the existing hose and reattach the fittings. If not, you'll need a new hose. No matter what, the brake will need to be refilled and bled.

Sorry for the minimal details ; I don't know a lot about bikes.
How can I verify if the hose is broken ? The rear brake is a hydraulic disc, yes. The lever is a Shimano BL-MT201 (and I think the caliper too).

I don't know how to refill and bleed the brake, but I gotta learn. I can't really go to a bike shop, it's far away and without my brake, it could be dangerous...
 
If you don't know a lot about bikes, then fixing a broken brake may best be left to a professional. We have them on this forum, but you have to provide better info. Otherwise, you're wasting their time. Detailed pictures would be a start.
 
Did you actually see fluid leaking from the bike/brake/calliper/lever? If so, you could post a picture so we could "see" what you see.

Also when brakepads are worn and you keep riding you could potentially wear out the brakepad carrier and push the plunger out to far so that the fluid is leaking out. That would be a fubar in most cases with these cheaper callipers cause there are no spare plungers and it would cost more to replace that tha instal a new calliper.

A bit more info and a few pictures/video would give us a better understanding of your current situation.

Also, these hydro-disc brakes are not brand stuf, so a local shop should be able to help.
 
Did you actually see fluid leaking from the bike/brake/calliper/lever?

Yes ! From the calliper ; more specifically, when I pressed the lever, I saw a liquid being expelled from the cable/ caliper junction.

Also when brakepads are worn and you keep riding you could potentially wear out the brakepad carrier and push the plunger out to far so that the fluid is leaking out. That would be a fubar in most cases with these cheaper callipers cause there are no spare plungers and it would cost more to replace that tha instal a new calliper.

The bike was refurbished by a professional and I ride it for 800km only. I honestly can't diagnose how the brakepads are, I have to learn...! :)
When I pull the lever, it's very soft (but it comes back to the original place, it's not "loose"), the bike doesn't brake. As you can see on the pictures, the cable is not screwed on the caliper because the leak came from here (and I unscrewed the cable a little bit more to see). There is no leak anymore...because there is no oil, I guess.

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First, it's a hose, not a cable. There's no wire inside. Second, that connector looks cross threaded. If it is, the caliper could be toast. Make sure that you can thread that connector in straight and true, with multiple turns of engagement before going any further. If the hose is not broken, and the connections are tight, the system needs to be filled and bled. You'll need the proper oil/fluid and a bleed kit.

Going off of the hose part number, this document should get you started.
 
First, it's a hose, not a cable. There's no wire inside. Second, that connector looks cross threaded. If it is, the caliper could be toast. Make sure that you can thread that connector in straight and true, with multiple turns of engagement before going any further. If the hose is not broken, and the connections are tight, the system needs to be filled and bled. You'll need the proper oil/fluid and a bleed kit.

Going off of the hose part number, this document should get you started.

The connector is cross threaded, but just because I've unscrewed (a little bit) it after the leak. I don't know why there was a leak anyway but the connector was almost like this, just a little bit engaged (and straight).
I'm gonna fill and bleed the system tomorrow afternoon, thanks.

The document is unavailable on this page : https://bike.shimano.com/fr-FR/products/components/pdp.P-SM-BH59-JK-SS.html
 
Looks like the olive/ nut are not correctly mounted, the hose nut should be tightend between 5 and 6Nm and the endpart end olive should be in flus


If the olive is not cerrectly pressed into the caliper it wil leak at that point.

Do you have a bicycle workshop around town? They should be able to tell you if this caliper is toast or they can fix it for your. They could also check the front brake. Also they could show you where to look for wear on the pads.
 
Do you have a bicycle workshop around town?

No, it's really far away and they were not really helpful on phone. :/
I can try elsewhere but I really have to find someone with a big car.

They should be able to tell you if this caliper is toast or they can fix it for your.
So either the caliper is toast, or the hose was simply not screwed in properly? But could it have damager the caliper?
 

Rather easy video, depending on the caliper bleedport you would need a different bleed kit. Starting point could be https://www.mantel.com/it/kit-di-spurgo-shimano-bleedingkit-tl-br

And yes, if the bolt was turned into the caliper with force in crostreading the bolt in the caliper this could be a total loss for the caliper. That would be one like this https://www.mantel.com/it/freno-a-disco-shimano-deore-br-mt200

If you search on the mantel webshop you also wil be able to find a hose kit with the correct fittings and fluids. If the hose-nut was not correclty seated and it did not damage the threads in the caliper it could be saved.

And if the nut is correctly seated usually there is roughly 3 thread visiable on this nut https://cdn.mantel.com/images/product.php?image_id=203551

I think that if you are able to puzzle an Ikea cupboard together you should be able to work on the brakes after viewing a lot of these bleed video's

You also would need to take out your wheel, that would also involve the nowledge on the belt tension and how to set or reset the hub interface so you would be able to shift with the hub.

I could not find a public and correct video for the enviolo hub removal with a belt
 
@Palmthree: I greatly encourage you to find any good Local Bicycle Store (not Specialized) and talk with them. Hydraulic brakes can be served by any bike mechanic.
Take me as an example. When I was ignorant in the repair matters, I was leaving the e-bike matters to Specialized workshop but the regular bike things were fixed by my most local bike mechanic.
 
I could not find a public and correct video for the enviolo hub removal with a belt
Something like that I guess :
I greatly encourage you to find any good Local Bicycle Store (not Specialized) and talk with them.
They are far away and the one I've called told me they don't repair Specialized E-Bikes (they don't have the software, even if it's not necessary here). It was like "Come with the bike, we'll see".
Yeah, thanks...I guess ?
You also would need to take out your wheel, that would also involve the nowledge on the belt tension and how to set or reset the hub interface so you would be able to shift with the hub.
I may need to take out the wheel, but that'll be the case as soon as I change my tires, belt or inner tube, won't it?
I think that if you are able to puzzle an Ikea cupboard together you should be able to work on the brakes after viewing a lot of these bleed video's
It's like magic for me. :D
I don't even know how to lift the bike...!
Have you looked into mobile bike repair services, wherein a mechanic comes to you in a van-based workshop?
Good idea but there is no service like that here (they seem to stay around cities...). I've found one non-professional guy, I'll call him tomorrow.
 
Do you have a friend or a nearby neighbor that is mechanically inclined? Hydraulic brakes are very simple and should be easy to fix if someone has worked on the brakes on their car or motorcycle. They are very similar to those on your bicycle.

Also, try looking on YouTube for videos on how to fix your problem. Ive fixed so many things that I didn’t have a clue on what to do, just by following along with a YouTube video.
 
Do you have a friend or a nearby neighbor that is mechanically inclined? Hydraulic brakes are very simple and should be easy to fix if someone has worked on the brakes on their car or motorcycle. They are very similar to those on your bicycle.
Not really. I may go to a car mechanic ?
Your brakes are NOT Specialized... any bike mechanic can repair them.
I know ; could it be that the hose needs changing? It goes through the frame and the engine compartment and they may be afraid of that. Anyway, I don't know, they just told me that they take care of the brands they sell and that they don't sell Specialized. I know I'm not a smart person, but I found it embarrassing to insist at the moment, she seemed in a hurry to hang up.
 
I know ; could it be that the hose needs changing? It goes through the frame and the engine compartment and they may be afraid of that. Anyway, I don't know, they just told me that they take care of the brands they sell and that they don't sell Specialized. I know I'm not a smart person, but I found it embarrassing to insist at the moment, she seemed in a hurry to hang up.
You do not need to replace the hydraulic line. The issue is at its end. Let them see your e-bike first.
 
...they take care of the brands they sell and that they don't sell Specialized....
Not uncommon. Ebikes are generally a lot more proprietary than regular bikes, so understandable that shops would only want to train up and keep parts for the ebikes they sell. Some don't work on ebikes at all — sometimes for fire insurance reasons.

Many direct-to-consumer ebike buyers learn the hard way that (a) ebikes, like cars, eventually need sevice, but (b) finding service is by no means guaranteed — especially for the cheapest bikes.
 
Hello,
A bike mechanic came and changed all the brake pads, cleaned the rear disc and replaced the rear brake fluid. He “glued” (with blue glue) the hose. He told me the pads were worn, I kept the old ones to check but they seem to have the same thickness as the new ones. I paid 210€ (30€ for the trip). The bike won't be economical this month. :D
 
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