Changing rear brakes.

[Kill Switch]

Question regarding changing rear brakes:



1.  I simply take the caliper off the rotor, correct?

2.  Easiest way to push the piston back?



Thanks much guys.



BTW, I get  much respect with the Tiger, even from Harley folks here in the states.  They like and remember the Triumph name.  



Best,



KS

[Chris Canning]

1.Caliper off

2.Pads out.

3.undo brake reservior cap.

4.Spray pistons with WD40

5.Press e'm back in with your thumbs,just watch the level of the brake fluid.



Chris

[52blackshadow]

Chris,

           This sounds dodgy to me!  What does WD40 do to the piston seals (Oil and Rubber don't normally go well together)?



Far better IMHO to find the correct brake grease (Silicon grease - usually available from scuba diving centres if you can't get it at a car parts store) and spread that on the pistons.  If they are too tight to push in by hand then you can wind them in gently with a G clamp.  Don't wind them individually because you are likely to just push one out with the back pressure when the other goes in - either put a piece of steel plate etc across both pistons and put the clamp in the middle, or use one clamp to hold a piston while winding the other piston in with a second clamp.



Remember to grease the pin before replacing it - copper grease is best.



Good luck,



Shadow.

[Badger]

Also it the pistons are coated in crap then a few squirts of brake cleaner and a tooth brush to remove this. I find the wife's toothbrush works best.  



Bob

[Chris Canning]

Hi Blackshadow



Dodgy!!! first disc braked bike i had was a three cylinder Kawasaki in 73 and have used the same process ever since,and drop my pads out 2 or 3 time a year on my Tiger,1100s and Gilera 180 runner and don't have any problems and whats that 31 years!!!



Chris

[52blackshadow]

Morning Chris,

                       it wasn't my intention to cast aspersions on your experience, simply to raise a valid question!  Common wisdom (I know it's not always right!) says that oil and normal grease can attack the rubber seals in brake callipers.  I don't know what the formula of WD40 is, but I suspect it contains something that might harm the rubber seals.



You may have been lucky enough to have run disc braked bikes for over 30 years without suffering any ill effects, but plenty of people run with bald tyres and don't slide off, it doesn't help the unfortunate ones who do hit problems.



Personally I'd invest in some silicon grease and know I'm not risking it.



Cheers,



Shadow.

[Kill Switch]

Brakes went on no problem.  



Thanks for the advice.

[52blackshadow]

I mailed the WD40 company with this question.  Their response is posted below.



"I would also recommend that you use a Silicone based product as there are now so many different rubber compounds on the market and WD-40 has been known to cause some rubber compounds to crack over a lengthy period of time."



Sounds like the odd quick spray is unlikely to do any harm, but repeated use might not be too good for your seals!



Personally I won't be spraying it on my calipers!



Cheers,



Shadow.

[Chris Canning]

Blimey i don't know weather to laugh or cry!!!!!,25 years ago when rubber was still used in things likes seals and tyres!!! and brake fluid stripped you skin of you hands never mind the paint you may have a point,even today brake fluid can still pretty evil stuff and thats just the otherside of the seal and your worried about something as bland as WD,bareing in mind what ever you spray on, your going to wipe it off straight away because of all the crap inside the caliper.



Blackshadow your peddling a old wifes tail had some relevance many years ago but things have moved on,it's the down side of the net i'm afraid were as when you got your info from places like motorcycle clubs stuff like that got stamped ASAP.





Chris

[Brock]

Shadow and Chris...there's an element of truth in what both of you are saying...I've seen WD40 have a weird effect on some rubber stuff...it's almost like it makes the rubber expand and distort. And I've stripped a few calipers myself (removing everything, seals and all) over the years.

To free up the pistons would be ok I suppose, 'cos the piston sliding into the bore would have most of the WD40 wiped off by the seals. Obviously different rubber compounds have different properties these days, and I'm a great believer in using the right stuff for the job.

[52blackshadow]

Thanks for the support Brock, I really don't care what anyone chooses to put on their brakes, but believe that they should choose, armed with all the relevant information.



And Chris C - You seem to think that because you started riding back in the 70's it makes you some sort of infallible font of knowledge.  You're keen on saying 'That's the trouble with the web these days'.  Well, I believe one of the problems with the internet is that people have a tendancy to accept what they read here as true, because it's written down.  Not all your opinions are right!  Try looking for balance sometime, rather than just putting down anyone who posts something that doesn't agree with your beliefs!



It's a shame really, because some of your opinions match mine very well (I'm also a BMW and Tiger owner / rider) but the point of a forum such as this is that we can all throw in our experiences and let others decide.



All the best,



Shadow.

[Badger]

I have just come off another forum where everyone seems to be laying into everyone else. It used to be a friendly and informative place to be. Let's not get like that here please. Try and respect others opinions and if you are not always right so what. We are only human.



Bob

[Robbie]

I have just come off another forum where everyone seems to be laying into everyone else.

Bob

What forum is that? I feel like a fight today. it's the weather and time of the year you know.

[Chris Canning]

I said i rode my first disc braked bike in the seventies i didn't say i started rideing a bike then!!!!.



If your not keen on WD40 i'm sure you can come up with a alternative,please tell us from your exsperience what you use,Brock you may have seen WD do things to rubber,there ain't any of that in modern day seals!!!



Chris

[Patrick the Scot]

As to the WD40 issue on rubber seals: We are constantly instructed by parts guys not to put WD40 on O-ring chains because "it will expand the rubber and ruin the chain"  I do not use WD40 on my Tiger's chain, but I do on the my dirtbike O-ring chain. I soak the chain with WD as I spin the tire to loosen up all the crap on the chain and then immediately rinse the chain with silicon spray.  It works great for cleaning the chain. I have had no O-ring failures that I know of, in fact the spockets have gone before the chain.  Of course that is a dirtbike chain and not road bike brakes...