Brake maintenance for idiots

Last weekend was a bit weird.  Arthritis pain in my right foot was a big part of it, but either I forgot how to ride, there was something wrong with the bike, or both.

On Sunday it seemed like my brakes had become less powerful.  Not the only occasion, but in particular felt like it took a long time to slow down when at one point the A127 suddenly dropped to 15mph, although I had a big gap to stop in as I had just overtaken all the Sunday drivers.  A whole queue of cars all being overtaken by me wee 125, crazy.

I cannot even understand what happened on Monday, but I lost confidence in my back brake so did all my braking with the front, and it felt as though it was less powerful before corners than the back one usually is.  Maybe it was just my confidence and being more cautious with it, and not being able to rely on my rubbish technique of coming off the brake gradually whilst accelerating in them.  But given Sunday I wonder if it may actually be the brake.

The back brake is just a drum and I know how to fiddle with that, which I believe is the correct technical term.  I replaced the shoe in March and the wear indicator is fine, and  I even tested it just after setting off on Monday morning and it seemed sharp enough, so I think the problem there was just with with my foot.

But I do not know anything about the front brake.  My entire understanding of it is just to look at the little bubble, and then do nothing.

The pads were replaced when I had it serviced last year, about 7.5k miles ago.  My first thought was to check them, but I have no idea how.  The manual says to look for grooves on them, and has an illustration at the same angle as the photo below.  Where should I be looking to see the grooves?

Of course maybe it would be obvious if it was not so dirty.  Am I supposed to clean down there?  My policy has been to leave it well alone out of fear of messing something up.  If so, what to use?  Is the regular “brake cleaner” I use for the drum okay or does it need to be a specialist “disc brake cleaner”?

I do not think the brake fluid was changed when I had the bike serviced, so that will be over three years old.  Could that have affected the operation this weekend?  It did seem to be a sudden thing, I had not noticed any problem previously.  Even on Saturday when I think I was riding around a constant bit of back brake due to a numb foot the front seemed fine.

Is there anything else I should be checking?


A bunch more photos, because I have no idea where I should be looking.


Old brake fluid can definitely be a factor here. The brakes on my little 125 CBF were completely different after i changed the fluid. Also, it does look like your pads are wearing thin but that shouldn’t be a problem now. Try replacing the brake fluid and see how that goes

My recommendation - look up Delboys Garage on youtube. Whole bunch of brake cleaning/pad replacement/fluid replacement vids, explained in simple terms that even I can follow… really helped me over winter as my brakes were getting pretty useless and covered in crap. Now shiny and effective.

Cheers.  Sounds like that is the first place to look then.

I will take a look at those videos, though having realized the bike is due a full service I still want to let a professional go over it. Last time I had a warped disc and had no idea, though I could tell the difference afterwards, and kind-of missed the feedback it gave.  So maybe this time it will just be easier to let them change the fluid if paying anyway.

the grooves in the brake pads can be seen on the picture below, can’t see them in your pictures but from the second to last picture you posted, it looks like there’s still a fair bit of pad material left on yours.

That said, if the back brake is less powerful than the front, there is definitely something amiss. Good idea to let the garage sort it out, especially if the bike is in anyway.

the grooves in the brake pads can be seen on the picture below, can't see them in your pictures but from the second to last picture you posted, it looks like there's still a fair bit of pad material left on yours.
That said, if the back brake is less powerful than the front, there is definitely something amiss. Good idea to let the garage sort it out, especially if the bike is in anyway. monkimark
Back brake will obviously be less powerful than front...

Tthose look like they need a bit of TLC. Give them a scrub with brake cleaner and a strong toothbrush.  

There’s far more to efficient brakes than the obvious thickness of the friction material, which incidently should be >1mm. My advice is if Michael cannot follow the instructions in the manual regarding the wear limit groove, which incidently is not a feature of all pad brands, then Michael should leave his brakes well alone and seek professional assistance.

Below is all the manual  says on the matter of brake maintenance, NT.  Looking at the angle depicted in the diagram I cannot see the pads, and looking between the fork and wheels, the second to last photo, shows shows no groves.  I believe when the pads (and disc) were replaced they were with OEM ones, though.

Not sure it the problem following those instructions is mine.  Mind, I was incapable of following the back brake instructions, as I did those myself instead of using a Yamaha dealer.

That photo was very helpful, monkimark, thanks.  It now makes sense of what I should be seeing and where.  Maybe they were not OEM pads after all then.  The grooves look like they would be too obvious to be be obscured by dirt.

The manual says nothing elsewhere about cleaning them, but as I need to go to Halfords I will buy some disc brake cleaner and give things a bit of a scrub to see how it all looks when clean.  Then next week find somewhere to book the bike in and let the professionals deal with the rest.


Ah yeah, got it the wrong way round when I typed it.

could be that the pads are contaminated

Since you don’t mind getting your hands dirty but aren’t too confident in the level of your mechanical skills I’d say the OMC would be ideal for you.

They’re even advertising a free 9 point bike check which includes brakes.

Maybe a daft question but you say you have arthritis in your right foot. Any chance you could have been riding the back brake without realising it?

Maybe you overheated the back brake and therefore you suffered some break fade due to it being too hot?

Had not really considered it for Monday, but it is possible.  That was Saturday’s part of the weekend’s weirdness, though.  My foot was feeling numb and I am pretty sure it was resting a little too hard on the brake peddle as the bike seemed less responsive and I ended up having to make a special effort to keep my foot away from it.

No problem on Sunday though, with either my foot or the back brake used on its own.  And I normally slow down gradually with engine braking approaching junctions, so it was only when I needed to brake more quickly, using both together, that it felt lacking.

Before setting off on Monday I had to replace the brake light as it had blown, so given the previous days I did test out the back brake to be sure it was okay before leaving the local streets, and it felt the same as usual.  Got as far as Faversham without issue when I stopped at a slight angle at a junction where I was going to turn right.  So I put my right foot down, which felt sore as it touched the ground and I almost dropped the bike.

After that I felt like I had no confidence in the back brake, which I assumed was just my confidence given the rest of the weekend and my foot, but maybe I had been dragging it a bit before then too?  I did stop and give it a look over, and even ended up adjusting the free play in the pedal as it seemed to give a lot more than it should.

I know this sounds like a stupid question

why are you using the rear brakes to stop that’s what the front brakes are for

because he has a cruiser

No wonder the manual does not say to clean down there, it is very difficult to get at.  It is a bit cleaner in general but I will need a longer handled brush to get to the edge of the pads.  But then the heavy rain came so that had to wait.

Unless something goes badly wrong this weekend, it is probably time to just leave it to the professionals for now.  Enough dirt got brushed out that maybe it may make a little difference.  Is that 9-point check at the OMC a normal thing or just a current offer?  The timing is out with a service due, but sounds it would particularly helpful to do at a later time.

I know this sounds like a stupid question
why are you using the rear brakes to stop that's what the front brakes are for
I thought the proper technique is to use both together, or use just back brake at slow speeds?

I use both for stopping from faster speeds, such as the ends of a dual carriageway, but generally to scrub speed I just add back brake to engine braking because it is instinctive and what feels comfortable to me.  Obviously if that it is not enough then I add front brake too.

Oddly I have never had driving lessons, so my only other braking experience is on a bicycle. But I just cannot find a good resting position for my foot where it is not constantly sitting on the brake.  So I think the instinctive thing is just due to my foot naturally tensing up during braking, which means it gets applied anyway.

Apart from the CBT, as I ride alone I am mostly self taught so have just done whatever feels comfortable rather than what is proper.    The real bad habit part of it is that I am usually, gently, still coming off the back brake going into corners whilst at the same time accelerating.  I keep trying to stop that, and it made relying on the front brake instead on Monday feel really uncomfortable.

I really have no excuse  for not doing lessons and tests, and getting rid of the bad habits, now other than laziness sorting something out.  If only someone just told me where and when to go I would be much happier.  But I have not had any braking mishaps since my first 100-or-so miles when I twice grabbed too much front brake at traffic lights, so whatever I am doing is working.