Re: Yamaha YZF- R15 S Owners Reviews and Experiences

Both engines are same, only tuning is slightly different. In r15s the tuning is done to get more power at lower end of rpm. However its not noticeable.

Re: Yamaha YZF- R15 S Owners Reviews and Experiences

The R15S is also lighter by a few KGs(3 or 4) than V2.0, so there its balanced. Rest they are exactly the same, except the seat.

Regards.

Re: Yamaha YZF- R15 S Owners Reviews and Experiences

Alright good fellas, need some advice here.

Bike - R15S (2016)
ODO - ~8000 KMs

Since a week or so, I've been observing that after riding the bike for say 20-30 KMs with good usage of front disc brake, I find the front brake lever free 'play' more than usual. (Let's say double for the ease)

The first time I observed that, I parked the bike, waited for it to cool down and then pressed the front brake lever 5-6 times quick, which then reduced the free play to original. I didn't face this for 3 days then. However today again the same thing happened while I was coming to office. I realized the free play suddenly is more than usual. Please note, even if the free play is more, the brake bite and feedback remains as good as usual, I just have to pull the lever more now.

I checked the front brake fluid by keeping the bike straight, its somewhere between the middle and lower end. And I've been noticing a slight grinding noise while applying front disc brake since some time, which I can feel on the handles too(its kinda of unusual to me, since it wasn't there before).

Any suggestions on this are appreciated. I have my 5th service day after tomorrow, so I can take it up with them accordingly.

Regards.

Re: Yamaha YZF- R15 S Owners Reviews and Experiences

Yeah I have been observing it too. Free play of the brake increases over period of time. Have taken it up to service center guys and all they do is remove air bubbles from the braking system. After this brake gives a wooden feeling. Don't know how this can be fixed.

Re: Yamaha YZF- R15 S Owners Reviews and Experiences

Well that's not good. Guess need to pull some big guns here..
[MENTION=69523]Ankey[/MENTION] @TheArcher84 @leech @Anunay @vijaycool @The Monk

Guys, sorry for the mentions, we've got 2 people including me with this query and a possible problem, see if you have any suggestions. Thanks much in Advance.

Regards.

Re: Yamaha YZF- R15 S Owners Reviews and Experiences

Hi Vinay,
Here you go.
Need to check these:
1. Check the brake pads. If worn replace it.
2. Generally brake fluid must be low if the play is increased. Top up. It happened with me exactly after 8000 kms.
3. If the brake pad is not worn ( I believe 8000 - 10000 km is the average life of brake pads), then open it clean it, rub on rough surface and put it back. After 50 km of run you will start feeling the bite. Also top up the brake fluid in this case too.

Check this and let us know.

Re: Yamaha YZF- R15 S Owners Reviews and Experiences

The first thing I checked when I encountered play in my braking are the disc pad and the brake fluid. Checked with svc guys and they said its all good. Not sure about cleaning and all but they have tightened the brakes in front of me by removing bubbles in it. Also, let me confirm you that bite was never an issue, its just that the lever has far greater play than it usually does.

Re: Yamaha YZF- R15 S Owners Reviews and Experiences

Check the brake pads? And also the master cylinder for leaks.

Re: Yamaha YZF- R15 S Owners Reviews and Experiences

Fluid top up. Open the reservoir and then check. Mostly it is happening because of that. I too had this. Master cylinder can hardly go wrong. But just check that too if my suggestion doesn't work.

Re: Yamaha YZF- R15 S Owners Reviews and Experiences

Much thanks for the quick assistance [MENTION=77010]Anunay[/MENTION] and [MENTION=79102]Kartik Shetty[/MENTION]

As I said the fluid shows between middle and lowest level so I guess that could be a culprit. The pads however don't show any sign of wear as the bite is still solid but I won't rule that out.
Regarding master cylinder, I hope that's not the case but I'll have all these 3 checked with the SVC on Friday.

Regards.

Re: Yamaha YZF- R15 S Owners Reviews and Experiences

I have not faced such situations before. But, My feeling is that the brake hose could be a culprit here. Might have some damages/blockages inside which cause the brake fluid not to flow properly, causing the free play. But, for this ODO I assume the brake hose should not be an issue.

How do you apply your brakes..one long slow hold or you do pumping action.

Re: Yamaha YZF- R15 S Owners Reviews and Experiences

Thanks for the response [MENTION=64547]TheArcher84[/MENTION]

I brake gradually with a long slow hold, almost 99% of the times. Rest 1% on from very high speeds I usually tend to do 2 to 3 slow pumps in controlled manner till the bike comes to required state of slowness. (Not sure how I picked this up but this is the reminiscent from my FZ times)

I'm suspecting the lack of fluid here myself, but the I'll have the SVC guys check the hose as well. (I hope that's not the case)

Regards.

Re: Yamaha YZF- R15 S Owners Reviews and Experiences

Sounds like air bubbles in the brake system. The brakes need to be bled properly. Another quick hack you can use is to tie the brake lever with a rag overnight. Tie it tight. The lever should be pulled in as far as possible. This helps with getting rid of the air in the brake system. Though this works only to an extent.

Does the R15 come with steel braided brake lines? Very hard braking (like what you would do on a track) will get the brakes to overheat and render them ineffective. Though this should not be the case on your bike, since you are using it to commute.

Re: Yamaha YZF- R15 S Owners Reviews and Experiences

Thanks for the response @The Monk ,appreciate that.

No tracks or very hard braking for me. 70% is highway rides and rest city commute, however I won't deny once in a while hard front braking is done, thanks to random people appearing out of nowhere in the middle.

I don't think we have steel braided lines in R15(S) but I'm not 100% sure because this info hasn't been mentioned anywhere. Probably senior and long term owners may know better.

**Today's update for some new light on this matter-
This morning when I got ready for work, I found the brake lever in original state (very less play, hard lever), so looked like overnight it reverted to normal. Strange!
However as soon as I rode some 6-7 KMs, the lever again got freed by the same amount of play I mentioned earlier, its almost 2 inches of play now. Does this indicate anything?
The brake bite once it gets applied is still pretty solid though. I highly suspect the brake fluid lack or god forbid bubbles in the line now.

Let me know if anything else needs to be checked or I'll simply go with the suggestions you and above gentlemen provided so far in tomorrow's free service.

Regards.

Re: Yamaha YZF- R15 S Owners Reviews and Experiences

Well, I guess I am late to the party. Brothers have provided all the info.
Anyhow, how old is the brake pad. If it is old replacing it with a new one will solve the issue.

Bubbles in the brake lines are a major culprit (R15 does not use steel braided lines, its a rubber line), If the brake pads are good and still have life in them, that means brake oil has gone bad. How old is the bake fluid? Instead of topping up, try replacing all the fluid (The brake fluid is hydrophilic, it means it absorbs water vapor over time and loses its properties). changing all of the brake fluid will solve the issue. It is pretty cheap and replacing is easy. Open the bleeding value at the bottom, and the reservoir on top, then when the old fluid starts draining slowly start filling the top reservoir (The amount of oil coming out of the bottom should be equal to the amount you pour at the top. this will ensure that all the old oil is drained. Make sure that the reservoir at the top does not go empty at any time of changing, or you will have bubbles in the line. keep bleeding the line, till you think all the old oil is out and close the bleed nipple. Then top up the reservoir and close. You can find a detailed thread with pics about it in Do it yourself section)

Apart from this, I don't think there is any problem with master cylinder or cracks in the brake line. They may wear or tear over long term ownership, but not so soon. I trust Yamaha quality.