[CR] Slipping Silver Shifter Solved (Was) Re: Silver DT levers slipping

(Example: Framebuilding)

Date: Mon, 13 Apr 2009 12:22:15 -0700
From: "Thomas Adams" <thomasthomasa@yahoo.com>
To: <classicrendezvous@bikelist.org>
Subject: [CR] Slipping Silver Shifter Solved (Was) Re: Silver DT levers slipping


Dear List:

Thanks to the many helpful tips I received on this.  Short answer:  put a washer inside the assembly, next to the stop plate, not on the outside u nder the bolthead. 

The Silver levers come with the usual square holed stop plate that slips ov er the shifter boss.  Next comes a critically sized washer that is suppos ed to slip over the shifter boss shaft and into a recess inside the lever.   THe washer is supposed to space the lever far out enough from the sto p plate to allow the bolt to draw the assembly tight and resist the pull of the derailleur spring.  On mine the washer was too thin;  the lever bo dy made contact with the stop plate before reaching optimal tighness.  Re sult, a floppy lever with no holding power.

I discovered the fix by trying both washers on one side.  Voila. the bolt now drew tight enough to hold against the derailleur spring.  The only h ard part now was to find another correct sized washer.  Just like anythin g else on a bicycle, regular washers won't work.  A standard cut washer w ith an inside diameter large enough to fit over the shifter boss would look like a tea cup saucer on the inside of the assembly.  I eventually settl ed on a thrust bearing from Ace Hardware as a washer substitute.  The cri tical dimension is an inside diameter of about 3/8 of an inch, which slip s over the boss.  It's a bit looser than the original washer, but that doesn't seem to matter.

 BTW, order of assembly does matter.  It's crucial that the supplied wa sher be fitted next to the shift lever, as the recess in the lever is too s mall for the ersatz bearing/washer (outside diameter of 5/8 of an inch).  When I did it the wrong way around, the new washer rode against the outs ide of the recess with no pressure on the innards of the lever.  This   disabled the retro friction mechanism.  The sized washer fitting into the recess of  the lever body is necessary to engage the retro friction me chanism. 

The bearing/washer I settled on is a bit thicker than ideal (1/16 of an inc h) but the lever still mades adequate contact with the stop plate in the fu lly relaxed position, and the bolt had plenty of threads to engage.  I'll keep looking for a thinner washer substitute.

Strangely enough, the other lever, looking exactly identical and assembled on the right shifter boss of the same frame, reached tension without the ex tra washer.  Bikes is funny stuff sometimes. 

Tom Adams
Manhattan, KS


--- On Fri, 4/10/09, Thomas Adams wrote:


From: Thomas Adams <thomasthomasa@yahoo.com> Subject: [CR] Silver DT levers slipping To: classicrendezvous@bikelist.org Date: Friday, April 10, 2009, 8:58 AM

Dear Folks:

I'm trying to put a pair of the new silver DT levers, as sold by Rivendell

and Velo Orange on a frame, and the front derailleur spring is too strong f or the lever:  it pulls the lever back every time.  Has anyone else see n this problem?  The tension screw is not bottoming out, and I tried a wa sher under it:  still can't get the bolt tight enough to hold the front d erailleur.

Does anyone have a fix, to increase the holding power of these levers?  F YI, the levers are mounted on a Campagnolo dt boss, and the front derailleu r is an FSA Gossamer.  A simplex lever holds the derailleur fine, so it's not the derailleur. 

Thanks!

Tom Adams
Manhattan, KS