Shimano Road disc brake question

[boink]

Hi Hubbers

 

I recently bought a bike on Bike Hub that is fitted with Shimano Ultegra mechanical hydraulic disc shifters.

 

Since the brakes were the "wrong way around" for me (rear needs to be on the right for me) I took it down to my usual LBS and he did the switch. (A new hose needed to be bought due to internal cable routing etc.)

 

The front brake has been perfect, the back has been terrible since the change. 2 visits back to my normal LBS, re-seated hose, bled the brake, did stuff and no change. Lever pulls all the way to the bar and brake has very little stopping force. 

 

Tried an alternate LBS and they "sorted it out" with another bleed, fixed connectors that were apparently incorrectly installed and advice that I should be "pumping" the lever before braking.

 

The "pumping" does help but surely this is not a normal requirement? I have never had to do this on my disc equipped mountain bikes and its not ideal for riding in groups or traffic when there may not be time to pump the lever.

 

Has anyone else seen this and could you suggest what may be causing this? My happiness with my new bike is under stain with this iffy braking situation!

 

Thanks!

Mike

[WaynejG]

Can't offer a solution but when I want to stop I need to stop. Never heard of first pumping the brakes. Sounds like a fine way to loose some teeth.

[Jewbacca]

It has been bled and installed badly......

[Rudii]

Might be a silly question but did they check the brake pads? Had to do the "pumping" thing a while ago on my mtb and all it was was the brake pads being klaar.

[Schnavel]

Hi Hubbers

 

I recently bought a bike on Bike Hub that is fitted with Shimano Ultegra mechanical hydraulic disc shifters.

 

Since the brakes were the "wrong way around" for me (rear needs to be on the right for me) I took it down to my usual LBS and he did the switch. (A new hose needed to be bought due to internal cable routing etc.)

 

The front brake has been perfect, the back has been terrible since the change. 2 visits back to my normal LBS, re-seated hose, bled the brake, did stuff and no change. Lever pulls all the way to the bar and brake has very little stopping force. 

 

Tried an alternate LBS and they "sorted it out" with another bleed, fixed connectors that were apparently incorrectly installed and advice that I should be "pumping" the lever before braking.

 

The "pumping" does help but surely this is not a normal requirement? I have never had to do this on my disc equipped mountain bikes and its not ideal for riding in groups or traffic when there may not be time to pump the lever.

 

Has anyone else seen this and could you suggest what may be causing this? My happiness with my new bike is under stain with this iffy braking situation!

 

Thanks!

Mike

 

Take it to someone who knows what they are doing...

[Eldron]

There is air in the system. Internal hoses are a bugger sometimes because they wind around and change direction.

 

Place bike on back wheel and tap various bits of the bike (including the caliper) to get air bubbles to lever - pop the funnel on after a few hours of waiting/tapping then check for bubbles.

 

Failing that check the pads like someone else mentioned. They seem to get chewed up faster on road bikes than instinct would suggest.

 

I ride the same brakes and they are razor sharp. Don't live with badly bled brakes.

[100Tours]

Agreed - I have Shimano road hydraulics on 2x bikes now and they are some of the best I've ever had. Easy to set up and service too.

 

If you have internally routed hoses you may have an issue with damage to the hose where you can't see it.

[The Ouzo]

As others have said, get it fixed, even if it means new hoses and fittings.

I did a ride where halfway through the back brake went straight to the bars. It was a slow ride as it was a memorial ride, but it was still scary only having half the braking power.

 

I would not ride that bike until it is sorted.

[NickGM]

Don't live with badly bled brakes.

Nobody lives all that long with badly bled brakes.

[bertusras]

There is air in the system. Internal hoses are a bugger sometimes because they wind around and change direction.

 

Place bike on back wheel and tap various bits of the bike (including the caliper) to get air bubbles to lever - pop the funnel on after a few hours of waiting/tapping then check for bubbles.

 

Failing that check the pads like someone else mentioned. They seem to get chewed up faster on road bikes than instinct would suggest.

 

I ride the same brakes and they are razor sharp. Don't live with badly bled brakes.

 

Lever pulling to the bar would indicate air in the system for sure.

[David Marshall]

Everything above and check that the hose inserts are the road ones and that the reach adjustment is set to maximum reach before re bleeding. 

[MudLark]

Hi Hubbers

 

I recently bought a bike on Bike Hub that is fitted with Shimano Ultegra mechanical hydraulic disc shifters.

 

Since the brakes were the "wrong way around" for me (rear needs to be on the right for me) I took it down to my usual LBS and he did the switch. (A new hose needed to be bought due to internal cable routing etc.)

 

The front brake has been perfect, the back has been terrible since the change. 2 visits back to my normal LBS, re-seated hose, bled the brake, did stuff and no change. Lever pulls all the way to the bar and brake has very little stopping force. 

 

Tried an alternate LBS and they "sorted it out" with another bleed, fixed connectors that were apparently incorrectly installed and advice that I should be "pumping" the lever before braking.

 

The "pumping" does help but surely this is not a normal requirement? I have never had to do this on my disc equipped mountain bikes and its not ideal for riding in groups or traffic when there may not be time to pump the lever.

 

Has anyone else seen this and could you suggest what may be causing this? My happiness with my new bike is under stain with this iffy braking situation!

 

Thanks!

Mike

 

 

Mike, to answer your question: I have exactly the same set up on my road bike (Ultegra 11 spd hydraulic) and I have had a number of "left to right" brake changes along the lines that you discuss on various bikes with Shimano hydraulic brakes. And I have certainly never experienced the problem that you are experiencing. The technical problems are in all likelihood along the lines suggested above. But one thing is absolutely clear: Neither of the bike shops is doing the work properly. Either that or something has been irremediably damaged somewhere and somebody is not telling you about it. As for the advice that you should pump the brake before using it – whoever is telling you that is a dangerous idiot that should not be allowed anywhere near a bicycle, especially when we are talking high speed road bikes.

Edited July 8, 2020 by MudLark

[boink]

Thanks for the feedback everyone and 100% agree that iffy brakes are a disaster waiting to happen!

 

In short it seems that I need to find a third bike shop to take my problem to where the ask will have to be "pls strip the entire brake hose etc. out of the frame and start again".

 

Anyone have a suggestion on where I might take the bike in the Durbanville area?  

[MudLark]

Thanks for the feedback everyone and 100% agree that iffy brakes are a disaster waiting to happen!

 

In short it seems that I need to find a third bike shop to take my problem to where the ask will have to be "pls strip the entire brake hose etc. out of the frame and start again".

 

Anyone have a suggestion on where I might take the bike in the Durbanville area?  

 

I am not in the Western Cape but let me say that when I am concerned about a particular issue and I want to be sure that the job is done properly, I take my bike to FourWays CycleLab and I stand there and I watched the technician do the job and make sure I understand exactly what the issues are, et cetera. It might cost a little bit more than my local bike shop but I know the thing is done properly by the time I walk out of there. I speak under correction, but my understanding is that all of their technicians are also properly trained and formally qualified. Which believe it or not, does actually make a difference as opposed to the guy who simply learned "the backyard trade". The other thing is that they usually have all the correct tools for the job – as opposed to "making do" as many local bike shops.

[Paul Ruinaard]

I am also using these levers and no problems.

 

You are 99% certain its bleeding and then also a lack of desire to fix your problems as its work.

 

 

[CAAD4]

I am not in the Western Cape but let me say that when I am concerned about a particular issue and I want to be sure that the job is done properly, I take my bike to FourWays CycleLab and I stand there and I watched the technician do the job and make sure I understand exactly what the issues are, et cetera. It might cost a little bit more than my local bike shop but I know the thing is done properly by the time I walk out of there. I speak under correction, but my understanding is that all of their technicians are also properly trained and formally qualified. Which believe it or not, does actually make a difference as opposed to the guy who simply learned "the backyard trade". The other thing is that they usually have all the correct tools for the job – as opposed to "making do" as many local bike shops.

What do they charge you to supervise their mechanics?