Loose linkage in M739 XT v brakes

[Pyro Tim]

you don't ride it upside down Doug

 

[wookiee]

you don't ride it upside down Doug

Ok smart arse but they rattle...if I were going over bumpy ground I dont want to risk putting the brakes on at the tyre rubbing stage and ruin my tyres and my life!

 

[FluffyChicken]

5mm is a lot, far more than any I've seen and more than most brake surfaces give for vertical tolerance .

I didn't say how you could change them as never tried but I'm sure someone could come up with a way to nip them of, make a new one, tap them or thread them back in...

though just get rid as spares and get some other brakes.

 

[wookiee]

Thankfully Ant has stepped up with some Karma arms! Hopefully should be able to get a working set out of the 2..

...Thanks for all the help again guys

Doug

 

[Spudly]

I can't see how you could replace the vertical bar on the brake arm...the movement vertically of the brake pad is probably around 5mm so with the bike upside down the pads rub the sidewall of the tyre!!

Ive seen that you have this sorted now, but thats fairly normal, mine rub the tyre walls a little when the bike is inverted, but they only just skim it a very small amount, not enough to cause any blowout worries when on rough ground in fairness!

 

[wookiee]

I can't see how you could replace the vertical bar on the brake arm...the movement vertically of the brake pad is probably around 5mm so with the bike upside down the pads rub the sidewall of the tyre!!

Ive seen that you have this sorted now, but thats fairly normal, mine rub the tyre walls a little when the bike is inverted, but they only just skim it a very small amount, not enough to cause any blowout worries when on rough ground in fairness!

My fear would be on bumpy terrain that they would rattle around and when the brake was applied the pads could be in the "upper" position and cut into the tyre wall. As I said before the movement of the pad up and down is around 5mm so making it very hard to line up correctly on the rim also...

 

[Spudly]

Hmm, that does sound a hell of a lot, and i can clearly see your concern there in fairness, i always try not to spin my wheels when the bike is upside down (for whatever reason) because of the ever so slight contact that you get, and my pads are lined up as perfectly as i can get them, and im very particular about the setup of them, have to be perfect spring tension so the both move exactly the same and such lol!

 

[wookiee]

Hmm, that does sound a hell of a lot, and i can clearly see your concern there in fairness, i always try not to spin my wheels when the bike is upside down (for whatever reason) because of the ever so slight contact that you get, and my pads are lined up as perfectly as i can get them, and im very particular about the setup of them, have to be perfect spring tension so the both move exactly the same and such lol!

Perhaps this is why now more modern XT v brakes have stopped using the parallel push design! (never had this problem with cantis! )