Concerns with RadCity 5 Plus Hydraulic Brakes

[salaryman]

Hi There - please forgive the unsophisticated attempt at trying to figure out what I need to do.
I purchased my RadCity 5 Plus in May 2022 and have put about 2,000 miles on it so far. I had it installed/built and delivered to my home.
Very happy with the bike, which comes with hydraulic brakes caliper (and levers). I have never had this type of brake system and it didn't feel
right to me-when I used the levers to stop they didn't feel solid at all and felt quite loose. I called Rad's
tech support and the technician was not very professional but did tell me to go get it checked. I took it it and the tech there said
that he needed to "bleed" the brakes since they use oil. It cost me about $60 and Rad paid me back as it was still under warranty. Unfortunately the issue hasn't
been resolved. When I ride now I need to pump the brakes a couple times before they have resistance on the levers and allow me to make a stop.

My questions are:

1. What should hydraulic brakes feel like - is it normal for the levers to have so much slack/give in them?
2. Why would a new bike need to be "bleed"?
3. Since the "bleeding" didn't really make a difference is there something else that could be causing this, like the cables?

Your help would help me have a better discussion with Rad and not sound like a completely fool!

Thank you

Roger

 

[fooferdoggie]

Hi There - please forgive the unsophisticated attempt at trying to figure out what I need to do.
I purchased my RadCity 5 Plus in May 2022 and have put about 2,000 miles on it so far. I had it installed/built and delivered to my home.
Very happy with the bike, which comes with hydraulic brakes caliper (and levers). I have never had this type of brake system and it didn't feel
right to me-when I used the levers to stop they didn't feel solid at all and felt quite loose. I called Rad's
tech support and the technician was not very professional but did tell me to go get it checked. I took it it and the tech there said
that he needed to "bleed" the brakes since they use oil. It cost me about $60 and Rad paid me back as it was still under warranty. Unfortunately the issue hasn't
been resolved. When I ride now I need to pump the brakes a couple times before they have resistance on the levers and allow me to make a stop.

My questions are:

1. What should hydraulic brakes feel like - is it normal for the levers to have so much slack/give in them?
2. Why would a new bike need to be "bleed"?
3. Since the "bleeding" didn't really make a difference is there something else that could be causing this, like the cables?

Your help would help me have a better discussion with Rad and not sound like a completely fool!

Thank you

Roger

so you have to pump them every time you use them? are the levers bottoming out or they just stop when you pull them but don't stop you? if they got air in the line they would need bled. the pads could be worn out too.

 

[tomjasz]

Take the bike to a good LBS and they can sort in no time.

 

[salaryman]

Thank you FooFerFoggie & Tomjasz -The levers feel like they are bottoming out but they will come to a stop. I have also opened up a support ticket with Rad now that I have a better understanding of brakes.

 

[fooferdoggie]

Thank you FooFerFoggie & Tomjasz -The levers feel like they are bottoming out but they will come to a stop. I have also opened up a support ticket with Rad now that I have a better understanding of brakes.

rad uses such cheap parts its hard too say but it may be worn out pads and maybe discs though your milage is not high enough for discs. watch the pads when you squeeze the lever see how the pads move make sure they are even and see how they retract.

 

[tomjasz]

rad uses such cheap parts

They’re still workable. Not everyone can justify expensive Bosch systems. A good LBS can handle value priced brakes. A majority of the market BTW.

 

[tomjasz]

May 2022 and have put about 2,000 miles

Time for a tuneup. Easy peasy.

 

[fooferdoggie]

They’re still workable. Not everyone can justify expensive Bosch systems. A good LBS can handle value priced brakes. A majority of the market BTW.

my brakes are Shimano. but the lowest end brakes are somewhat workable the example above. with name brand parts you know what's going on.

 

[tomjasz]

my brakes are Shimano. but the lowest end brakes are somewhat workable the example above. with name brand parts you know what's going on.

Snob. Almost true…
BTW Shimano has low end stuff too.

 

[jabberwocky]

Hydraulics vary in lever feel but should feel reasonably firm. If theres a lot of movement after you feel the initial "bite" of the pads touching the rotor, thats probably indicative of an issue. Especially true if braking force is low. A quick perusal of Rads site just says they are "Rad approved hydraulics", so no idea what brakes it actually comes with.

Things to check:

2k miles is enough that it could be pads wearing out. How long pads go depends on conditions you ride in, but thats not a totally insane mileage for a pad replacement, especially if the bike came with cheap organic pads. If its pads it usually feels normal at the lever, you just lose a lot of braking force since the brake piston is pushing the metal pad backer into the rotor instead of the actual high-friction pad.

Spongy levers are often a sign of air in the system. Hydraulic brakes work by compressing a non-compressible fluid at the lever, which flows through the hose and moves the piston at the caliper to squeeze the rotor. Most bike brake systems are sealed so air should have trouble getting in, but over time tiny amounts do and since air will compress, your lever gets spongy or rubbery feeling instead of firm. Bleeding the brakes is the process of pushing fluid through to dislodge air bubbles and pull them out so the system only has brake fluid in it. The fluids used also absorb water over time which lowers their boiling point, so fluid should be changed out occasionally for that reason as well. I've been running hydraulic brakes for almost 2 decades now and in my experience a good quality brake needs a bleed every few years.

A note on fluids: almost everyone uses the same fluids as car/motorcycle brake systems (DOT 4 or 5.1 brake fluid). The two major exceptions (I know of at least) are Shimano and Magura, who use mineral oil.

Last thing to check is contaminated pads. If oil or something gets on the rotor and contaminates the pads, it can mess with braking a lot. Solution is to remove the pads and clean them (sand the outer layer off, bake them in the oven to burn off contaminates, etc).

Any shop outta be able to evaluate things and figure out whats going on. Hope that helps.

 

[fooferdoggie]

Snob. Almost true…
BTW Shimano has low end stuff too.

yep but its well documented and supported.

 

[fooferdoggie]

H

A note on fluids: almost everyone uses the same fluids as car/motorcycle brake systems (DOT 4 or 5.1 brake fluid). The two major exceptions (I know of at least) are Shimano and Magura, who use mineral oil.

actually few use DOT fluid anymore mineral oil is the standard on most name brand brakes out there. like tectro and such are all mineral oi. for Has many drawbacks anymore.

 

[jabberwocky]

I obviously don't really keep up with the market. Sram (I still think of them as Avid but Sram has owned Avid for years now), Formula, Hope and Hayes are still DOT fluid. Shimano, Magura and (apparently) Tektro are mineral oil. The swaths of cheap chinese imports on Amazon and the like all seem to be mineral oil as well these days, so you could very well be right that its the new standard. I have brakes that run both and don't really notice a difference between them, though just anecdotally my mineral oil brakes seem to need bleeding more frequently.

Mineral oil is easier to work with at least. DOT fluid is nasty. Mineral oil you can lick your fingers after working with. DOT fluid dissolves paint.

 

[fooferdoggie]

I obviously don't really keep up with the market. Sram (I still think of them as Avid but Sram has owned Avid for years now), Formula, Hope and Hayes are still DOT fluid. Shimano, Magura and (apparently) Tektro are mineral oil. The swaths of cheap chinese imports on Amazon and the like all seem to be mineral oil as well these days, so you could very well be right that its the new standard. I have brakes that run both and don't really notice a difference between them, though just anecdotally my mineral oil brakes seem to need bleeding more frequently.

Mineral oil is easier to work with at least. DOT fluid is nasty. Mineral oil you can lick your fingers after working with. DOT fluid dissolves paint.

ya its both ways the the cheapies are all mineral from what I see. me I would end up with DOT everywhere god I used to be messy doing my brakes.

 

[tomjasz]

yep but its well documented and supported.

Seriously? Cheap but documented? A pdf doesn’t improve low end quality. Don’t be a Boscholite evangelical and look down and find the need to demean someone’s eBike when they come for help. Help or shut the…

 

[tomjasz]

with name brand parts you know what's going on.

So there aren’t enough Rad eBikes in the wild for there to be documentation? seriously?

 

[jabberwocky]

So there aren’t enough Rad eBikes in the wild for there to be documentation? seriously?

I suspect the issue with Rad documention is that they don't stick to a specific brand/model/oem for brakes (and likely other parts, for that matter). Which is why its just listed as "Rad approved hydraulics", so they can swap to whatever they can get cheapest at that moment.

Not that its a huge deal, bike brakes are fairly simple and there isn't a ton you need to know for basic maintenance like changing pads or bleeding. On the low end, if the brakes need anything beyond that (rebuild seals or similar) you likely just replace them. For no-name Chinese imports the major questions are "what pads are they using" (generally they just make their pads match some Shimano brake), and "where are the bleed ports and what fitting do they take?" (again, generally just match the fittings from some popular brand like Shimano). Any shop wrench outta be able to figure that out in a few minutes just looking at them.

 

[AHicks]

Oh for Pete's sake. Lets keep our focus on the OP's question? The answer is easy. If they pump up, that 60. bleed job is faulty. The fact they pump up at all is indicative of 1. a 99.999% chance of air in the system, and 2. the repair shop that charged you 60. to bleed did a crappy job.

That's where I would start. The shop you paid to fix this problem. They SHOULD be willing to give it another shot. If not, if they won't have another look at it, it's really not Rad's fault, and you need to find a different shop that's hopefully more competent. My thought, FWIW. -Al

 

[salaryman]

I suspect the issue with Rad documention is that they don't stick to a specific brand/model/oem for brakes (and likely other parts, for that matter). Which is why its just listed as "Rad approved hydraulics", so they can swap to whatever they can get cheapest at that moment.

Not that its a huge deal, bike brakes are fairly simple and there isn't a ton you need to know for basic maintenance like changing pads or bleeding. On the low end, if the brakes need anything beyond that (rebuild seals or similar) you likely just replace them. For no-name Chinese imports the major questions are "what pads are they using" (generally they just make their pads match some Shimano brake), and "where are the bleed ports and what fitting do they take?" (again, generally just match the fittings from some popular brand like Shimano). Any shop wrench outta be able to figure that out in a few minutes just looking at them.

Hi Jabberwocky-thank you so much for the details and easy to understand explanation. Rad asked that I send them videos showing what the levers look like when I squeeze them. I will report back on what they find and suggest.

 

[salaryman]

Oh for Pete's sake. Lets keep our focus on the OP's question? The answer is easy. If they pump up, that 60. bleed job is faulty. The fact they pump up at all is indicative of 1. a 99.999% chance of air in the system, and 2. the repair shop that charged you 60. to bleed did a crappy job.

That's where I would start. The shop you paid to fix this problem. They SHOULD be willing to give it another shot. If not, if they won't have another look at it, it's really not Rad's fault, and you need to find a different shop that's hopefully more competent. My thought, FWIW. -Al

Great point-and thank you. I will call them and see what they say!