Help needed with RK rear brakes

[Hunter]

Hey Guys!

I had an NDE today.. heheh... my rear brakes completely failed when doing about 80mph coming into an intersection!!

I managed to get the bike under control without killing myself or the bike using the front brakes alone.

The confusing thing is that after I stopped the bike and pumped the rear brake pedal a few times it was back to normal!

Can anybody suggest anything that I could do to make sure this does not happen again... I think i've only got a few lives left..!!

Cheers!

[Guest]

erm........... you should be using the front brake to slow down from high speeds anyway- apply front just before back for an emergency stop. Just using the back you are likely to lock the rear wheel, because under braking all the weight's over the front (no offense intended, just helful advice).

[Kickstart]

Hi

I agree with anonymous, but you probably need to bleed your rear brakes. Brake fluid absorbs water, which will just about work as a hydraulic fluid, but when you use the brakes plenty of heat is generated, and this will boil the water, turning it into water vapour which will compress and give you a spongy brake

All the best

Keith

[G]

as ^they^ said use the front brake... you do need to be carefull in wet conditions, but it'll still stop you a whole load quicker than the back even then. The quickest way to stop is when you've got the back wheel just about to come off the ground... at this point the back brake should be left well alone.

[Hunter]

Yes I agree the front brakes are *much* more effective but I was quite concerned when the rear just failed like that. I don't know if it was water but when I kept pumping the brakes it got back to normal!

I hope that this is not a sign of masterpump (rear) failure cause there is absulutely no one is Sri Lanka who sells them!!

Any input would be greatly appreciated..

Cheers for the support!

[G]

If you were using it a lot for quite a while it could well just have been the fluid boiling... especially if it hasn't been changed in a while.

[Hunter]

Yeah.. that sounds about right as I was really giving it stick down the straights and really squeezing on the rear brakes (as well as the fronts).

Also I recall just touching the rear disc lightly (slight tap) with my finger and it was *quite* hot.. i swear I heard it sizzle..heheh

Do any of you guys have nasty noises coming out of your gear boxes when down shifting? Mine sounds like its being tapped by a hammer! everytime I downshift.

Does this happen when the gear oil is not changed frequently enough? or if there is a problem with the clutch? or the gears themselves?

See.. i got the bike from this guy who hasn't used it past the 4th gear.. does not have a clue about servicing (has been giving it to Honda for services), and don't know what needs servicing.

Thanks guys for any help on this!!

[G]

if you were using the front as well it's less likley... In my experience rear brakes don't usually get put through too much shit, becasue you can't have them on that hard without the rear locking.

It's probably still worth replacing the brake fluid. I'm not sure how much it would cost in Sri Lanka but its about £1.50 for brake fluid and the same for a bleeding kit in the uk, so you might as well.

[Hunter]

Cheers G!

Three questions.. what is a bleeding kit, what does it look like, and can I improvise as I'm not sure if these are locally available!

Thanks again!

[NovaMuncher]

How long should your rear brakes last? i know this is a difficult question to ask but mine have gone and they have only done 3000 miles. also they have worn really unevenly. one is completly gone and the other is only gone by about a third Hmmmmmmmmmmm!!!!!. it might be because it did 1600 in the middle of london lots of stop starts..!!!

[G]

A bleeding kit is basically just a length of clear plastic tube, usually with some kind of valve assembly at one end and a washer of some sort. You put the open end onto your brake, fasten it on by sliding the washer over the nozzle, then put he other end (with valve) into an empty jar.
They are the same as ones used for cars so they shouldn't be too hard to find...
If you do want to make one, you'll have to be carefull with the type of tube you use... brake fuild eats body work and paint so I doubt plastic is safe. You can easily enough use a cable tie (smallish one with teeth closer together) instead of a correctly sized washer, and the valve isn't too important.

[Hunter]

Thanks G for the great info! I'll try and find one thats meant for a car.. I have seen people do it with just a tube and a jar before.

Any ideas on how to empty/drain out all the old brake fluid before I re-fill?

Thanks again for your help on this!

[G]

Not sure how much you know, so here's the basics of what you need to do:

First you need to get the bike so the reservoir is as level as possible.
Take the cover off the reservoir, making sure you keep all the stuff away from dust etc.
Cover the bodywork around the reservoir with an old rag to prevent any fluid getting on it.

Attach your tube to the bleed nipple and put the other end in the jar, secure tightly around the nipple.
Undo the nut underneath the nipple, the brake fluid should start to seep out, make sure none is leaking from the seeal between the tube and nipple.

*Gently* press/pull on the brake leaver, fluid should start to come out through the tube, note the colour.
When the fluid reaches the 'lower' mark on the reservoir, top it up with fresh fluid.
Repeat until the colour of the fluid coming out though the tube has lightened and is therefore fresh fluid.

Top up so that it's at the maximum line, close the nut underneath the bleed nipple then replcae the covers & remove the tube.

Remeber: brake fluid eats bodywork, so be *very* carefull.

[Hunter]

Is this the same procedure for both the front and the rear brakes?

Thanks G for the great help!

[G]

Yeh, it's the same for both.

Varous people on here helped me when I first got my NSR, so I'm quite happy to reciprocate.... And I'm still trying to find an excuse to not do tidying .