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BenBoozer 11-05-20 11:58 AM

Issue with 105 hydraulic brakes
 
Hello,
I purchased a 2020 Domane SL5 new three months ago. I'm pretty sure it has the Shimano 105 R7020 sti shifters. I noticed yesterday that the left (front) brake lever does not return to the full released position after I apply the brakes. It only returns about half way and the pads are still lightly in contact with the rotor. I have to use my fingers to push the lever back. The springy feeling of the right brake is absent in the left one. Since this is my first hydraulic brake bike, I plan to take it back to the LBS and have them look at it but I have a few questions:
  1. What happened to the springy feeling?
  2. When I apply brakes, why do both levers reach the bar tape?
  3. I read you should not turn your bike upside down, how do you change flats?
Any answers would be appreciated.

BenBoozer 11-08-20 10:58 AM

Anyone have any ideas? I’m new to this but it seems like I might want the shop to bleed the brakes at least. No problem stopping yet, but not liking how far I have to pull before locking up.

Amt0571 11-08-20 04:20 PM


Originally Posted by BenBoozer (Post 21776488)
Hello,
I purchased a 2020 Domane SL5 new three months ago. I'm pretty sure it has the Shimano 105 R7020 sti shifters. I noticed yesterday that the left (front) brake lever does not return to the full released position after I apply the brakes. It only returns about half way and the pads are still lightly in contact with the rotor. I have to use my fingers to push the lever back. The springy feeling of the right brake is absent in the left one. Since this is my first hydraulic brake bike, I plan to take it back to the LBS and have them look at it but I have a few questions:
  1. What happened to the springy feeling?
  2. When I apply brakes, why do both levers reach the bar tape?
  3. I read you should not turn your bike upside down, how do you change flats?
Any answers would be appreciated.

Bleed the brakes. There's something wrong there that will probably be solved if you do a bleed.

You can put the bike upside down to fix a flat. Don't worry about it. Just don't press the brake levers with the bike upside down or in vertical as air will probably get in the lines if you do.

If it happens, you can usually solve it by pressing the brake lever multiple times with the bike on its wheels.

After the bleed, check the reach adjust to check if it's way turned in, maybe this helps you bring the levers further from the handlebar when braking. In any case, hydraulic levers tend to have more travel than mechanical ones. You'll get used to it.

cpach 11-09-20 01:05 AM

That's an expensive bike, and even given these trying times the shop should be eager to sort you out--otherwise, why would you have bought from then other than a Canyon or the like?

Nothing horrible is going to happen if you invert the bike for while, but you should avoid storing it in that position for an extended period of time because air from the reservoir in the levers can migrate into the rest of the hydraulic line. Still, most experienced cyclists and nearly all mechanics agree that you should not invert a bike to fix a flat. It scuffs the tape and saddle and provides an excellent opportunity for the bike to tip over and smack a thin-walled carbon tube into something. You can simply release the brake with the bike upright, shift into the small/small, and remove the wheel, then set the bike down lightly on the left side on a preferably soft surface on the side of the road, fix the flat, and reinstall with the bike upright.

If one brake has an excessively soft feel it's probably air in the line and it requires a bleed.

Amt0571 11-09-20 01:40 AM


Originally Posted by cpach (Post 21781432)
Still, most experienced cyclists and nearly all mechanics agree that you should not invert a bike to fix a flat. It scuffs the tape and saddle and provides an excellent opportunity for the bike to tip over and smack a thin-walled carbon tube into something. You can simply release the brake with the bike upright, shift into the small/small, and remove the wheel, then set the bike down lightly on the left side on a preferably soft surface on the side of the road, fix the flat, and reinstall with the bike upright.

I strongly disagree. The saddle and the hoods are made from soft and flexible materials. If you invert the bike carefully and don't move it so that it slides over the surface, nothing bad will happen. If there's something hard, the padding of the seat or the hood rubber will absorb it instead of getting a scratch.

If you lay the bike on its side, there's potential for you to scratch the fork, the brifter, pedal, chainstay or even bend the derailleur hanger. Most "soft" surfaces have gravel, small stones or other hard things in them with potential to scratch your bike. Not to mention that you don't always have soft surfaces nearby when you flat, which guarantees that if you set the bike on its side, you're going to scratch it.

The only times where I don't invert the bike to fix a flat is if there's a soft surface nearby and it's a front tire flat. As it's easy to find a place where I can put the fork ends on the ground without damage.


Regarding storing the bike inverted, I have not done it, but due to a lack of space, I store the bikes hanging from the wall. One faces up, and the next one down. I always try to have hydraulic brake bikes facing up, but once I ran out of space and had a bike with Shimano SLX brakes on the down position. It was like this for a few weeks without issues. Not that I recommend it though.

ARider2 11-09-20 06:21 AM

I know it may not cause issues to put a bicycle with hydraulic disc brakes upside down but this is from the Shimano safety instructions (document SI-8KC0A-001-00) for their Deore disc brakes:

"When turning the bicycle upside down or on its side, the brake system may have some air bubbles inside the reservoir tank which are still there when the bleed screws are replaced, or which accumulate in various parts of the brake system when it is used for long periods. This disc brake system is not designed to be turned upside down. If the bicycle is turned upside down or on its side, the air bubbles inside the reservoir tank may move in the direction of the calipers. If the bicycle is ridden in this condition, there is the danger that the brakes may not operate and a serious accident could occur. If the bicycle has been turned upside down or on its side, be sure to operate the brake lever a few times to check that the brakes operate normally before riding the bicycle. If the brakes do not operate normally, adjust them by the following procedure.

Amt0571 11-09-20 08:14 AM


Originally Posted by ARider2 (Post 21781566)
I know it may not cause issues to put a bicycle with hydraulic disc brakes upside down but this is from the Shimano safety instructions (document SI-8KC0A-001-00) for their Deore disc brakes:

"When turning the bicycle upside down or on its side, the brake system may have some air bubbles inside the reservoir tank which are still there when the bleed screws are replaced, or which accumulate in various parts of the brake system when it is used for long periods. This disc brake system is not designed to be turned upside down. If the bicycle is turned upside down or on its side, the air bubbles inside the reservoir tank may move in the direction of the calipers. If the bicycle is ridden in this condition, there is the danger that the brakes may not operate and a serious accident could occur. If the bicycle has been turned upside down or on its side, be sure to operate the brake lever a few times to check that the brakes operate normally before riding the bicycle. If the brakes do not operate normally, adjust them by the following procedure.

Yes, it can happen. Although in my experience it's more likely to happen when you accidentally press the lever in a inverted or vertical position. It never happened to me when putting the brake upside down without touching the levers. In any case,it's nearly always solved by pressing the lever multiple times with the bike on a normal position, at first it has too much travel and it keeps diminishing on every press until it's normal again.

I always check the brakes before riding or if I have placed the bike upside down position.

wgscott 11-09-20 08:35 AM

OK, we now have Shimano's own instructions and a professional bike mechanic saying don't do it.

Why not err on the side of caution?

As for the OP, the brake might be in need of a bleed, or there is some internal mechanism malfunctioning, or the reach adjust might not have been set correctly. Since the bike was purchased under warranty 3 months ago, the shop should sort it out.

Even if the brake simply needs a bleed, you have to ask why this would be so after only 3 months.

BenBoozer 11-09-20 02:02 PM

Update. I dropped my bike off at the dealer about two hours ago where I demonstrated the issues. Within an hour, they called back where after troubleshooting, they got in touch with Shimano who was aware of the problem. They said it was an issue with or in the master cylinder (I can't remember which one he said) and it can not be serviced so they are sending out a new brake lever. Should be here next week. The mechanic bled some air out of the rear brake and now the lever doesn't travel all the way to the tape anymore. Glad this showed up under warranty and I appreciate all of your insight.


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