buying advice - old hopes or something newer

Kowalski675

The Rookie wrote:

The only slight change when using braided is IF it does reduce hose expansion

Back to "I've paid therefore it is" I think?

CAWT - hence my comment about MTB brake systems not operating at a high enough pressure ofr braided hoses to be of benefit - they're only of any benefit performance-wise if the hoses they're replacing are expanding. Even on a motorcycle stopping from 3 figure speeds, braided hoses only offer a genuinely worthwhile performance increase if they're replacing old worn out rubber hoses that are knackered (most folk fit them 'cos they look nice, and last indefinitely, since the PTFE inners don't degrade like OE rubber lines do) - gains over healthy new OE rubber hoses are real, but marginal.

Kowalski675

fizik wrote:

But in the real world all fluids are compressible, and the spongeyness at the end of the lever travel (unless you have air or high temps in the system) is a result of hoses expanding which in turn is a result of the compressed fluid.

What on earth are you on about? Brake fluid isn't compressible - that's the whole premise of how hydraulics work. If the fluid was compressing then the hose wouldn't need to expand, you've completely contradicted yourself there :roll:

The Rookie

fizik wrote:

The Rookie wrote:

I agree, but it is 'possible'.....

But in the real world all fluids are compressible, and the spongeyness at the end of the lever travel (unless you have air or high temps in the system) is a result of hoses expanding which in turn is a result of the compressed fluid.

OK lets cut the bullshit.....
Liquids are NOT compressible (gasses of course are a fluid and are, but you shouldn't have any), the hoses can expand slightly under pressure, that may change feel slightly (for better OR for worse, it could make a 'too sharp' brake feel right, or a 'too soft' feel worse). It has no effect on power despite your earlier assertions they definitely, absolutely certainly did, but which you now seem to concede they probably don't!
I can't imagine wanting my XT's to feel any different to how they do now, braided may or may not change the feel for better or for the worse, as I'm totally happy I'm not going to pay to find out.
Sponginess at the end of the travel can come from distortion in any part of the system, lever, hose, air in fluid or calliper (spreading open), compression of pads (worse with organic than sintered) non of which other than the hose will be affected by the change to braided hoses.

fizik

You are of course right about compressibility Rookie, my apologies. I will also concede that I wouldn't bother changing the hoses on a set of xt's just for the sake of it either. Fitting them on my bike has improved the lever feel and the initial bite, which as you point towards will change the feel of the power delivery and the initial bite, but not ultimate power under normal circumstances. I personally like this on off feel. my only regret is that I wish I helitaped my frame before fitting, they can make a mess of paintwork! sorry again for being an argumentative old sod.

Giraffoto

If I understand the course that this thread is taking, there is an assumption that a conventional brake hose is (to an invisible extent) taking up some of the braking force by expanding like a long thin balloon. Has anyone taken the trouble to check if this is happening? A micrometer should be enough. The same process should also be taking place along the length of the hose, which would be noticeable if it's happening - you'd see the hose move if it stretched by a millimetre.

Funnily enough, I'd always assumed (perhaps wrongly) that the braiding was to protect brake lines against rubbing.

Kowalski675

fizik wrote:

my only regret is that I wish I helitaped my frame before fitting, they can make a mess of paintwork!

Can't you get em with a paint friendly shrink wrap sleeve like ones for bikes without pedals?

The Rookie

Giraffoto wrote:

If I understand the course that this thread is taking, there is an assumption that a conventional brake hose is (to an invisible extent) taking up some of the braking force by expanding like a long thin balloon. Has anyone taken the trouble to check if this is happening?

To clarify we've now agreed that inflating the hose (if it did happen at all) as you describe would have no effect on power but may effect feel. It is not possible for that action to take any 'braking force'.

Levi_501

To add some comments from a Hope, Formula and Shimano (previous generation) user;

I have had Hope V2s on my commuter for about four years. They have the Hope Tech Flip-Flop lever, braded lines and floating rotors. For reference, they are fitted to an Orange R8 with Project 2 forks.

As I have said before, the V2s do not have quite the initial bite of the Formulas (we are not talking much) but they literally are bomb proof and unbelievably reliable.

They were fitted four years and have covered over 15,000 miles of London commuting (a savage test of anything bike!) in sun, wind, rain hail and snow; and they have performed absolutely faultlessly. I change the fluid once a year, but apart from that I never touch them. They never need adjusting, the pads last for years, they do not squeal and most importantly do not fade.

Regarding the braded hose part of the discussion, whilst I myself think there is limited performance benefit; I do think the lines do stay in better condition, as in the do not get damaged, crushed or alike.

Would I recommend or fit Hope brakes? In a heart beat.