Brakes

[Glasgow44]

Hi there

I'm looking for others' views/opinions.

The bike I'm referring to is a Bianchi Infinito CV Hydraulic Disc Brakes.

The front brake makes a squealing noise (its not a constant squealing when braking, its more like a short sharp yelp when I come to a stop).

Anyway, I booked the bike into my local bike shop who have said that they would look at it and do a brake service. This is what the mechanic has told me on the phone today:

The mechanic has said that the rear brake is fine but that the problem(s) are with the front brake and shifter. He has said that the front brake has contamination and when he was looking at the discs/pads, they were "glazed". He also said that the fluid is black when it should be pink and that the fluid is "cooked" (boiled up). He has also said that the master cylinder is corroded and that there is no pressure in the system. He has said that the "O" rings in the shifter are damaged and the whole shifter will need replaced.

 

[Oldhippy]

Personally I would switch to new pads myself and see what happens. Very simple to do. I'd have thought damaged O rings would result in leakage under pressure but I'm no expert.

 

[fossyant]

Hmm. Is everything working ?

Squeals are common. New pads, clean up discs with brake cleaner.

Will need a bleed though if fluid black.

Blast the calipers with brake cleaner too. Euro car parts for a big tin under £4

 

[T4tomo]

Hi there

I'm looking for others' views/opinions.

The bike I'm referring to is a Bianchi Infinito CV Hydraulic Disc Brakes.

The front brake makes a squealing noise (its not a constant squealing when braking, its more like a short sharp yelp when I come to a stop).

Anyway, I booked the bike into my local bike shop who have said that they would look at it and do a brake service. This is what the mechanic has told me on the phone today:

The mechanic has said that the rear brake is fine but that the problem(s) are with the front brake and shifter. He has said that the front brake has contamination and when he was looking at the discs/pads, they were "glazed". He also said that the fluid is black when it should be pink and that the fluid is "cooked" (boiled up). He has also said that the master cylinder is corroded and that there is no pressure in the system. He has said that the "O" rings in the shifter are damaged and the whole shifter will need replaced.

Do you have a reason to doubt what the LBS mechanic is saying or what are you actually asking?

Given the shifter is knackered, you aren't going to damage it further by changing pads are continuing to ride it, although you perhaps risk facial damage if it fails completely.

A new shifter will be expensive - is your model still being sold new to get just a LH one, or is it new pair time?

 

[Glasgow44]

Do you have a reason to doubt what the LBS mechanic is saying or what are you actually asking?

Given the shifter is knackered, you aren't going to damage it further by changing pads are continuing to ride it, although you perhaps risk facial damage if it fails completely.

A new shifter will be expensive - is your model still being sold new to get just a LH one, or is it new pair time?

I have no reason to doubt what the mechanic is saying. I'm basically just asking what others' views are - that's all.

He didn't mention getting a new pair of shifters, just the left one.

The mechanic has advised that I don't ride the bike and I'm not going to.

 

[cougie uk]

Hi there

I'm looking for others' views/opinions.

The bike I'm referring to is a Bianchi Infinito CV Hydraulic Disc Brakes.

The front brake makes a squealing noise (its not a constant squealing when braking, its more like a short sharp yelp when I come to a stop).

Anyway, I booked the bike into my local bike shop who have said that they would look at it and do a brake service. This is what the mechanic has told me on the phone today:

The mechanic has said that the rear brake is fine but that the problem(s) are with the front brake and shifter. He has said that the front brake has contamination and when he was looking at the discs/pads, they were "glazed". He also said that the fluid is black when it should be pink and that the fluid is "cooked" (boiled up). He has also said that the master cylinder is corroded and that there is no pressure in the system. He has said that the "O" rings in the shifter are damaged and the whole shifter will need replaced.

How old is the bike ? How many miles on it ?

 

[Glasgow44]

How old is the bike ? How many miles on it ?

The bike was bought in February 2020. I'm not sure how many miles are on it. I had problems with the shifters on this bike making a "buzzing" noise, namely the left one (which is for the rear brake); the dealer I purchased it from carried out a repair and this problem is better than it was, although not completely gone.

 

[Smokin Joe]

I'd take it somewhere else for a second opinion. If the only problem you experienced was a squeal and the brakes were otherwise ok with no fluid loss the mechanics diagnosis seems a bit over the top.

 

[T4tomo]

Hmmm that's not long for issues to have developed with both shifter /brake units, but I guess it still means you can get hold of I presume a 8020 RH shifter / caliper unit, rather than having to fork out for a pair. Still expensive. if the LBS the supplying dealer? if so the might do you a deal as it should last far longer than 2 years.

Nice bike Btw I have an older rim brake model. My RH shifter went and I ended up having to find one on ebay as they were no longer available new.

 

[Glasgow44]

Hmmm that's not long for issues to have developed with both shifter /brake units, but I guess it still means you can get hold of I presume a 8020 RH shifter / caliper unit, rather than having to fork out for a pair. Still expensive. if the LBS the supplying dealer? if so the might do you a deal as it should last far longer than 2 years.

Nice bike Btw I have an older rim brake model. My RH shifter went and I ended up having to find one on ebay as they were no longer available new.

I agree. Its not a long time at all. I'm wondering if there was maybe an inherent problem there all the time?

 

[Lookrider]

Cannot advise at all on the mechanics
But does that component not come under a 2 year warranty ?

 

[si_c]

It is possible that you need to replace the shifter, but I would be very surprised. The only o-ring that is really accessible that I know of (others may know more) is the top bleed port o-ring, you can get replacements for those from SJS cycles (see here). If the fluid is black then it's contaminated and needs replacing, it's most likely that the o-ring has deteriorated and that's caused the contamination, I seriously doubt the master cylinder is damaged.

My thoughts would be to replace the pads, and then to drain and fully replace the fluid in the system, flushing it properly and replace the top seal. Worst case scenario you've spent a fiver on brake fluid and a couple of quid on an o-ring.

 

[Glasgow44]

It is possible that you need to replace the shifter, but I would be very surprised. The only o-ring that is really accessible that I know of (others may know more) is the top bleed port o-ring, you can get replacements for those from SJS cycles (see here). If the fluid is black then it's contaminated and needs replacing, it's most likely that the o-ring has deteriorated and that's caused the contamination, I seriously doubt the master cylinder is damaged.

My thoughts would be to replace the pads, and then to drain and fully replace the fluid in the system, flushing it properly and replace the top seal. Worst case scenario you've spent a fiver on brake fluid and a couple of quid on an o-ring.

The thing is: the bike shop have already serviced the rear brakes; these "major problems" are with the front brakes/shifter. Do I just pay for the work already carried out then take the bike elsewhere for a second opinion on the front brakes/shifters? The bike hasn't covered a lot of miles and is not that old; I was quite taken aback when he mentioned problems with the master cylinder.

I'd take it somewhere else for a second opinion. If the only problem you experienced was a squeal and the brakes were otherwise ok with no fluid loss the mechanics diagnosis seems a bit over the top.

Even as a lay person with very limited bike mechanic knowledge, that's what I thought too.

Do I just pay for the work already carried out on the rear brakes and then take it elsewhere for a second opinion re. the front brakes/shifter?

 

[Smokin Joe]

Do I just pay for the work already carried out on the rear brakes and then take it elsewhere for a second opinion re. the front brakes/shifter?

That's what I would do.

 

[si_c]

The thing is: the bike shop have already serviced the rear brakes; these "major problems" are with the front brakes/shifter. Do I just pay for the work already carried out then take the bike elsewhere for a second opinion on the front brakes/shifters? The bike hasn't covered a lot of miles and is not that old; I was quite taken aback when he mentioned problems with the master cylinder.

Even as a lay person with very limited bike mechanic knowledge, that's what I thought too.

Do I just pay for the work already carried out on the rear brakes and then take it elsewhere for a second opinion re. the front brakes/shifter?

i wouldn't necessarily take it anywhere else if you have a good rapport with the bike shop, just tell them what you want them to do then settle up.