Ducati Sporting Club UK > General > Idle Chat > Everybody loves a knowall ...

[madmav]

No Offence taken Nb's!!
hopefully we can all learn some things we don't know
i've been in the trade all my life and am still learning new things every day so c'mon guys bring it on


but just to make one point i think if you can get into the realms of linear measurment then suspension set up becomes a lot more understandable!!!
but it's way way beyond me

just my opinion

[NBs996]

it's beyond me too!

i had a suspension guru round my gaff not so long ago to help me out and try'n teach me something. I described to him what the bike was doing and he 'tuned' it out for me... it worked too! Quite happy, was I

Happy, but still no wiser!!

[Redruth]

Nick, you are far too wise already! You MUST be grateful that there are still some things in life that are a mystery even to you.

[Redruth]

Ok, well in the absence of anything more challenging, I have a question. Why do my front brakes lock up in these circumstances:

1. Ride the bike on a cold winter's day.
2. Hose it off and put it in the garage
3. Next time I come to move it, I can't budge it.
4. Try to bump it up and down a bit and it and eventually manage to move it forward but it makes a horrible grinding noise.
5. Brake lever seems much stiffer for the first few miles but then eases up.
6. Is it safe to keep riding it when this happens?

This is a genuine question based on real facts. No names have been changed to protect anyone at all.

[NBs996]

Ahem!

It's just a case of the wet causing a little corrosion between the disc and pads. Not sure why the lever should feel stiffer tho?
No problem to keep riding it.

[Redruth]

You've got this whole 'Teacher's Pet' thing going on haven't you Nick

Thanks for that. Is the corrosion anything to worry about, though? And which bit is corroding?

[NBs996]

The iron content of the disc is turning rusty, and there'll be some metals in the friction material which might corrode in their own little way too.

It's only a tiny bit of surface rust and won't be a problem until it gets to the state where you can't free it, no matter how hard you try! Then you might have to take the callipers off (leaving the pads stuck to the discs) and then pry the pads off with your best serving spoon - but that's worst case scenario.

If it annoys you (more than I do), then dry it off as much as possible before putting bike to bed.

[748mart]

I would say that the caliper pistons are sticking.

Remedy: clean calipers & work pistons in & out until runing smooth.

[NBs996]

As a postscript, it doesn't have to be wet to do this.

If left long enough, two different metal elements will corrode each other without the need for water. It's got something to do with the different electrostatic properties of metals at an atomic level but that probably won't be noticable unless you leave you bike so long that the next time you use it it's for a trip to collect your pension! And for you ruthie, that many many years away!

[NBs996]

Originally posted by 748mart
I would say that the caliper pistons are sticking.

Remedy: clean calipers & work pistons in & out until runing smooth.

you refer to the stiffer lever action?
I would agree. Give that man a point!