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Existentialism-- Just a bloody good excuse to go riding...

Tuesday, March 20, 2012

DCL Revelation

Or rather its just stupid me again... finally figuring out 4 yrs after not bothering with the red free-stroke adjustment.

While the freedom of an uncluttered bar and the absence of shifter paddles is great, brakes on the Dual Controls aren't exactly something to sing about. Bled properly its not lacking in strength but certainly not for people who swears by grabby brakes-- the kind that with a touch is gonna throw your lungs out of the mouth.

For the usual offroad riding that's not a problem for me. However I sure wish for a more precise braking system when out on urban rides and popping off a few pivots or having better modulation on a wheelie.

Somehow with an inverted resevoir (I suspect) bits of air gets in one way or another, slowly beating the damn brakes to a mushy feel. Opening and releasing those bubbles followed by a top up is not diffucult but....

When everything is new with lever having a precise feel (no play) new pads and all- many have commented (including me) that the red free stroke did squat to the feel of the brake. Free of bubbles it does makes a small diff making the contact-grab feel more or less positive depending on whether the free stroke dial is fully open or close.... but still not really enuf that once set, its pretty much forgotten as most time my mind is more tuned to suspension characteristics and other things on the bike.

Until... tonight. Was squeezing out all the air from the rear brake and somehow the damn thing just seem to need some Viagra added to the mineral oil.. Gave up after 2 hrs and thought maybe its time to ditch the damn thing. Went and did the front brake which took all of but 5 mins..

Was mulling what could be wrong until I saw that little red dial staring at me.. Looked on both sides and realized that the front brake side was fully closed but opened all the way on the rear brake.
-Closed it and the lever contact-grab feel was much better.
-Open up resevoir once again and last few residual bubbles pop right out with some light squeeze...

The free stroke adjustment.. .its kinda hard to peer at as its on the underside when lever is mounted (misplaced reading glasses certainly didn't help) to try and figure out which is open or close.  So...

Stand behind bike
Front- rotate anti-clockkwise all the way in until dial press against back of the cylinder = closed, min free stroke.
Rear- like the front back it up against the cyclinder but have to rotate clockwise for closed position on the freestroke.

Do the above before re-bleeding brakes... and the maintenance takes just a couple of minutes and minus an hour long of expletives...

Looks like everything's good to go for now and the spare pairr of  DCL can sit for awhile more in storage....

Got me thinking-- so why the free stroke makes a diff when brakes are properly bled but more importantly why the effect is much more pronounced when the brakes are old and well used....

Looking at everything as a whole, it would seem like the Servo-wave path  doesn't really work that well after the bushing of the roller pin has been worn  down with use. This leads to a "stuck" feeling of the lever on some days. Especially when its wet and muddy and the brake's been hard at work for a few hours.. quick solution is to clean out the gunk and just lightly lubricate.

Of course with things that are worn, its usually accompanied by play. All of these just makes it sounds like time to junk the brakes. But the "revelation" tonight was the little free-stroke dial  that's tucked out of sight  most time-- is the key to get the brake back up on par and working with less annoyance. Minimizing the free stroke means decreasing the lever pull in a way (yes there is the lever adjustment dial but the two dials work a little differently w.r.t. to amount of  lever pull)... the less to pull, the less loose play due to wear of the other parts. That may not have been its original purpose but I'm glad to have made the connection and .... still stop the bike with my old mangy but trusty DCLs for awhile more.

So why all the fuss and not just change the thing. Well if some useful lifespan can be eke out of it Im not apt to throw them away... El Cheapo? No, not in this case. Its just something personal where I reckon most of us are living in a lifestyle of excess. A bin full of  extra stems and bars is what I would consider "essential" that can be looked at as "tools", use whenever setting up a new bike and trying on various combos to get a bike done up correctly. But brakes are brakes-- if they work they work and not changing means leaving a smaller carbon footprint (or at least that's how I would like to believe). Let someone else have a new bike and a new brakeset to enjoy their ride. I'm still good with what I have.

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