Re: [CR]Safety levers (tech)

(Example: Production Builders:Cinelli:Laser)

From: "dddd" <dddd@pacbell.net>
To: "Classic Rendezvous" <classicrendezvous@bikelist.org>
References: <002401c6b728$91e533d0$6101a8c0@Dickey>
Subject: Re: [CR]Safety levers (tech)
Date: Fri, 4 Aug 2006 14:48:57 -0700
reply-type=original

Dickey Greer wrote:
> They had too much leverage and would lock-up.

I've used these levers on bikes that I still ride today, and have no issues with leverage, even riding steep paved and dirt roads. The finger's distance from the lever axis seems about the same for both levers. A more-upright rider might tend to transfer weight more abruptly because of the torso pivoting foreward, however, and I seem to have noticed this, with braking from the drops feeling more steady. I've also noticed that today's "cyclocross" (Runkel) levers afford much less leverage than the main levers do, probably for this reason, and to good effect.

Two other problems of "safety levers" were:

1) The loss of lever travel (curable, and only a problem with the most popular versions of these levers).

2) Excess pivot freeplay (also curable).

The auxilliary levers were robust solid forgings in almost all cases. Shimano and Weinmann (after 1978 or so) offered levers that "plugged into" the side of the main lever rather than hooking atop it, meaning no loss of main lever travel, and Weinmann's pivots also became refined (and seemingly non-serviceable) at that time.

Mafac brake levers had arguably too much reach and travel to begin with, so their version, even if retro'd with Dia-Compe's (or their own) safety levers, still afforded mucho travel from either lever. Mafac offered an extended lever pivot with a flimsy circlip, poor engineering imo, and that could snag on a glove's finger.

The fix for reduced lever travel is as simple as trimming away a couple of millimeters from the front edge of the lever body, letting the safety lever's "hook" return a little further upward. The fix for loose pivots is usually as simple as discarding the internally splined washer, then shortening the "lock spring" that's inside the threaded bore of Dia-Compe's pivot shaft. Tightening the screw fully home with Loctite on the threads may now give a no-slop pivoting action to even a well-aged plastic-bushed pivot, if some attention is payed to the amount of compression that the screw now applies.

I get years of hard service from the basic Dia-Compe safety levers, and have nice, anatomically-shaped hoods fitted as well. The safety levers seem to offer near-comparable braking (i.e. plenty) to the main levers, while allowing comfortable riding (especially seated descending) on a bike otherwise fitted for road riding performance.

It's too bad that the levers (and bikes) were typically not so well set up. Better lever operation (and better-built rear wheels) might have done much to extend the era of the 10-speed's popularity with the masses. I've put several of those former "roadies" back on bike-boom steeds, and with a couple of extra hours of conscientious assembly, they are keeping at it in painless-to-the-eyes, twenty-seven-inch STYLE.

David Snyder
Auburn, CA USA