Differences in braking

[d3vi@nt]

This will probably be overly vague, but here goes. I want my '99 ST2 to brake more like my '07 M695. What does that mean? Well, I'm not really sure. The Monster just seems to brake better, more precisely.

The Monster has 2-piston 2x300mm discs, where the ST has 4-piston 2x320mm discs. The ST has about 100 pounds on the Monster. The Monster has braided lines, versus the ST's rubber lines. I plan to upgrade the ST lines, but I'm not convinced that will make a huge difference.

Given the suspension on the ST is better than the Monster, what other differences might contribute to the lesser braking performance? One caveat is that I don't know what pads are on either bike...

[Dirty Duc]

Braided lines do make a difference, especially if the rubber lines are old.  They get mushy after a while (and if you are used to braided lines, they feel mushy anyway).

Is that the specific difference you're feeling?  I don't know.

[Howie]

Definitely upgrade to the steel lines, particularly if they are original.  Brake fluid might be old too, but that will be history when you change the lines anyway.  See how it is after that and we will take it from there.

[Speeddog]

What howie said.

Upgrade and see what you think then.

[Slide Panda]

Hail hail the gangs all here... one for for the steel lines camp.

To go into a little more detail for you.
Rubber brake lines, even new, expand some when pressure is introduced to the system - ie you hit the brakes. As they age, they can develop weak spots that will even bubble in the worst cases that further reduce the translation of force from the master to the calipers.

Steel lines will expand/flex a bit when you hit the brakes - but a lot less.

[d3vi@nt]

Thanks for all the feedback. New lines are next on the to-do list and I'll probably throw new pads on the front, since I have no idea what's on there currently.

As I think about it more, I'm starting to believe that part of the difference is due to the suspension. Though the suspension is rougher, the Monster doesn't nose-dive as much, where the ST is smoother but dives more. I'll have to see if I can figure that one out, as well.

[Slide Panda]

Poorly performing or setup suspension can reduce braking efficacy.

Last year I got a KTM 690 Enduro. The owners manual has a series of recommended click settings for the suspension. The 'Sport' setting was 10 clicks (0 being all in and as stiff is it could be). After a few rides my tail bone was killing me and I was wondering if something was wrong with the front brake. After flushing the fluid, cleaning the rotor and pads the braking was still lack luster despite it being a 300 pound bike with as much front brake as bikes weighing 100 pounds more.

Doing some reading lead me to the suspension - the recommended settings from KTM are WAY to stiff. The result was that the forks were so resistant to compressing that the front wheel was chattering a small amount causing crappy brake performance. Revisiting all the suspension settings has greatly improved the comfort (not more sore tail bone) and brake performance.

So that's the long way of saying that - yes out of whack suspension can hamper braking.

[d3vi@nt]

Well, thanks to you guys (and Spiegler) I'm now $300 poorer. 

Figured I'd do the clutch line while I was at it, so that added to the cost. I planned on doing it sooner or later, but guess I needed a nudge. Or an excuse (DMF made me do it).

SP; thanks for the suspension notes. I've got fresh oil in the forks, but other than verifying the rear suspension is set to factory, I haven't messed with it. I have a habit of making things worse than they were to begin with, but I can hopefully get it sorted.

[suzyj]

Stuff the steel lines. Just get in there with an angle grinder and find 50kg.

The ST's brakes are hugely better than a stock 695.

[Slide Panda]

Stuff the steel lines. Just get in there with an angle grinder and find 50kg.

Not everyone's got magical engineering skills like you Ms. J. 50 kg is a lot... might need to halve the rider to get that much off.

[koko64]

If you need an excuse to spend more $$$, I found changing to a radial master cylinder improved leverage, feel and therefore braking confidence.
I went to EBC HH pads, braided lines and a radial m/c. Very good upgrade ("safety first") .

[SpikeC]

When I replaced the rubber lines with steel braided on my old BMW K100 it was as if I had replaced the entire system. New pads are likely to have a big effect as well, but the lines.........

[d3vi@nt]

Thanks for all the suggestions. I'll probably hold off on the radial masters due to cost. And dropping 50kg probably isn't realistic for me. I'll likely go for a lighter rear sprocket and rear rotor when their due and possibly CF cans if I can find a used pair. Of course, all that weight savings will be negated as soon as I throw a six-pack in a side bag.

I checked the front suspension settings. Factory is 11 of 14 for rebound and 12 of 14 for compression, 14 being the softest. The actual settings were 9 for rebound and 11 for compression. But starting in the first groove, I counted up 15 clicks.  Either way, I left the rebound at 9 and dropped the compression from 11 to 10, hoping to decrease the front diving.  I'll have to wait until the weekend to see if I can tell a difference.  I'm pretty clueless on suspension, though. Am I on the right track?

[Slide Panda]

Just going by clicks is relatively useless - sorry.

has your suspension been serviced withing the last year - forks and shock? If not, playing with the clickers is probably a pointless exercise as the oil in either/both is crap. The oils in suspension components do get worked (shearing) frothed and heated as well as contaminated with gunk from inside the suspension as it works.

This is my drain bucket after doing a couple fork legs that only had about 4000 miles on them.


A rough rough starting point for suspension:
Compression: Set the clickers to the middle of the range.
Rebound: Set so the bike fully returns to it's base ride height in about 1 seconds time from an sharp downward force though the chassis. Ensure that the front and rear rise at even rates.

From there' you gotta ride it some and take note of how it feels and tire wear to help inform any additional adjustments. Tire wear can tell you a lot about rebound, not so much about compression damping.

[jerryz]

 4 pot brakes Pads will need regular de-glazing and discs need cleaning with solvent or they lose bite