HI have only been riding since the late spring. This is my first bike. It does NOT have ABS (I've heard air can get trapped in the ABS system...this is not my issue).

Several months ago, I changed the brake fluid. I initially had air sucked into the front brake line, but it eventually came back out the other side. The rear brake caliper initially seemed to be "sticking" a bit after the fluid change, but now no longer sticks at all and I can freely rotate the wheel when cleaning the chain.

I had a recall on something NOT brake related. While there, the mechanic told me my brakes needed work because they felt "spongy". They then quoted me a whopping $650 for an 8k mile service. I told them I'd think about it. They said they could knock off some items if I am doing things myself but still. I'd like to see if I can figure it out myself.

I tried to re-bleed them for a while yesterday, but no air came out of the lines. The brakes feel the same. I tried tapping on the brake lines a bit as well. Still no bubbles come out.

I do not have a pneumatic bleeder. Instead I do this method. 1. Pump brake a few times then hold down, 2. Open bleeder valve for a few seconds, 3. Close bleeder valve, 4. Release brake.

The brake pads have plenty of meat left on them, also confirmed by the mechanic.

However, a new thing that just developed after attempting to re-bleed is that the rear wheel now squeals when rolled backwards. Not sure if that has any relation.

Since this is the only bike I've owned, I also don't really know how they are "supposed" to feel. This is how they've always felt ever since owning the bike before I even changed the fluid.

Bike is from 2017. The fluid looked dirty when I initially got the bike in spring of 2026, so I don't know how old the fluid in the bike was.

Any ideas? Would you mind explaining for someone not super well-versed in mechanical things? All of this bike maintenance stuff is new to me!

Thanks all!

Ignore what the mechanic said, and find a new shop. Any mechanic that takes that approach is scum, and I grew up in the shop business - my father would say "I don't need to screw anyone to make a buck".

That mechanic was saying you need to replace everything at that kind of price. If that were true, you'd know - that bike would be terrifying to ride with brakes as bad as he's saying.

Rear wheel squeek is probably nothing more than a pad that's worn in to match the rotor - rolling backward it probably rubs a little. If you don't hear a squeak otherwise, I wouldn't worry.

Your bleeding process is right. Bikes are a little finicky because there's so little fluid. Use a rubber band on the brake handle - that'll free up your hand.

I doubt anything is wrong. Does it feel spongy when you squeeze, or does it feel like there's a point where you'd have to really squeeze to move the brake handle more?

Spongy brakes are usually air in the lines, but a bad brake line (the rubber part) can feel the same. When they get weak, they'll expand under pressure. But I doubt such a bee bike would have this issue. Hell, I've ridden 1980's bikes that were fine.

There's an inexpensive tool to help with brake bleeding - it's a small plastic bottle with a special top to prevent pulling air back in. It's not required, but can make it easier when bleeding by yourself.

Lol!!! To be fair, they quoted me for an entire 8K mi service (bike had 5.1k miles). It included a bunch of stuff, but most of it is stuff that I have been doing myself....oil change, coolant change, brake fluid change, chain clean and adjustment, etc. I was just like "holy shit" at the price for that stuff hahaha.

He did confirm that the brake pads looked good so it probably just needed a bleed. It wasn't a quote to replace the brakes.

I did actually buy and use that little bottle! It is quite handy, but I still tried to not let go of the brakes with the bleeder valve cracked open just in case. I used it more as a failsafe. I actually DID get a bubble out of the front brake line several months ago. But that was after I initially accidentally got air into the line myself when I let the fluid get too low in the reservoir while flushing it.

Both brakes have a some degree of "dead zone" travel before the brakes engage. But at least for the front brake it seems to engage rather quickly once it is engaged. The rear brake feels less so, but it is really hard for me to tell. For the rear brake, I do have difficulty engaging it with my more protective moto boots, but I thought it was because I can't move my ankle. I had to adjust my shifter up to use my more protective boots and was thinking about moving the rear brake lever up as well. When I am not wearing my more protective boots, it is much easier to engage. However, I still am able to do hill stops with the rear brake even with my more protective boots.

Both brakes seem "less responsive" than I remember my MSF class bike. But I also didn't have my fine motor control as developed back then and I can't compare them side by side.

How can I determine if my brake lines are having issues? I don't have a garage, so it it bakes outdoors in the Florida sun, heat, and rain. I suspect that may have been the case for its prior owners as well.

Try lightly tieing your brake lever up overnight, if the air can travel up it will. But aside from that does the lever feel firmer after a few pumps? That's a really good sign air is in the system.

Is it a sliding caliper? Very easy to have sticky pins on those. You only have 5k on it but a wore out disc can feel spongy as well. The spec should be stamped on the disc its self.

No, it doesn't seem to feel firmer after a few pumps. It's the same after pumping them.

Some people on another community were trying to tell me about the zip tie overnight method. Do I bleed them again after doing this?

I'm not sure what kind of caliper. How do I tell if the pins are "sticky"?

If the rear brake can stop you, then it's fine. Rear brakes (on cars and bikes) are more for control than stopping - front does nearly all the braking.

From your description your brakes sound fine - every bike is a little different. I'd expect a little play before engagement.

Every bike I've had needed a little adjustment to suite me - I tend to need a little more play in the rear brake, guess my right foot likes to hang down.

some bikes have a return/alignment clip on the rear caliper. shops frequently lose them, might be your issue. it's not serious at all though.

The condtion of your brake lines and theoretically wear in the seals in the master cylinders can also affect brake feel. This is usually a problem found largely in bikes that have been sitting for a long time, though.

Since your bike does not have ABS: Can you readily lock both wheels with the brakes? If so, they're fine.

@dingus If a mechanic can't think past 'air in the lines', get a better mechanic.

I wasn't there for the brakes. I was there for a recall unrelated to the brakes. They didn't do any sort of comprehensive diagnostics.

My bike is on the older side...2017. I do not have much knowledge of previous ownership. It is quite possible that it was sitting unused for a while. The tires were original and dry-rotted when I got the bike.

I am a bit scared to try to purposefully lock up the brakes lol but I can try to test it some time soon.

Trust me, model year 2017 is not on the "older side." I've ridden bikes from the '80s with perfectly functional original brake components.

Locking the rear wheel in motion should be no problem. For the front, do it from a standstill instead: See if under moderate engine power you can overcome the force of the front brake. And on the bright side, if you need to replace any brake components on a non-ABS bike it should be doable with just a handful of tools in any parking lot.

I bleed the brakes on my bikes backwards, meaning that I use a big syringe to push brake fluid in from the caliper up to the master cylinder. This must be done from the caliper that sits furthest away from the master cylinder in the front, usually the left side. Works better than the traditional approach in most cases. Might be worth a shot!

I agree.

Honda rebel right? Looks like sliding calipers to me. If pumping doesn't produce a firmer feel, it doesn't need any further bleeding. Does the lever come all the way to the bar when you try stopping hard? What bike are you comparing the feel to?

No, I cannot pull the front brake lever to the bar when stopping hard. I can only do it when I open the bleed valve during bleeding. The rear brake lever doesn't seem to hit an obvious "wall" like the front one does tho. It just gains more resistance as I push down on it, but eventually I cannot push it down any further (unless I open the bleed valve). I think the rear brake may actually be "soft", but the front brake is probably fine.

Unfortunately that's the problem. I don't have a bike to compare to. This is my first bike and I've been riding it since around May/June. It was the mechanic who said the brakes were spongy. I took a couple day MSF course a while back but I can't remember much about the differences in the brakes other than the MSF bike (brand new) felt more sudden to stop...but I also didn't have fine motor control yet for the controls.

Here is a schematic of my rear brake caliper.

https://www.partzilla.com/catalog/honda/motorcycle/2017/cmx300-ac-rebel-300/rear-brake-caliper

Do you know what things I should be checking on here? I'm a bit lost as to how to troubleshoot this stuff.

the piece i'm talking about is either 8 or 6, probably 6. it usually clips over the brake pads and puts them in the correct position.

also check if the guide pins for the caliper are properly lubricated (assuming it's 20 and/or 16 here). it can also cause it to not return correctly.

This was car, but just in case...

Last time I couldn't finish a bleed on my own, it turned out that there was a bullshit part of the ABS system that wouldn't open to get bled without a subscription to a special software service.

So I ended up having to take it to a mechanic to finish the bleed.

Hopefully that's not your issue. I saw you said it doesn't have ABS.

In that case just ride it, maybe go on ride outs and keep an eye out for other rebel riders and grab their levers.

Just about 40 years riding and this is also how I do it.

What the actual fuck??? I've heard of air getting trapped in the ABS systems but I've never heard of it being paywalled. Fucking ridiculous.

My bike is fairly low tech! Doesn't seem to have anything like that. Doesn't even have a tachometer or gear shift indicator (and yeah no ABS).

I have heard of this! Interesting! Do you have to re-bleed the regular way after that? How messy is this lol?

Ok I tested a couple of times and I seem to be able to lock up the rear fairly easily. But the tires were prob cold. Can you easily lock them up with air in the lines still?

The front brake lever has some freeplay and then I hit a sudden wall of resistance, which to me seems fairly normal? I tried to do a bit of what you said but I am a bit nervous of being loud and potentially doing burnouts in my condo complex lol!!

The rear pedal doesn't have the same feel as the front lever. Instead of hitting a wall, I just feel a gradual increase in resistance until I can't push it anymore. It doesn't feel sharp like the front does for me and the pedal can travel fairly far. However, I cannot bottom them out unless I am bleeding the brakes and opening the bleeder valve.