Classic & Vintage - Simplex front derailleur limit adjustment?

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gems
05-27-11, 09:55 AM
How do you adjust the limit on a front Simplex? There is one screw and I can't figure out what it does... The derailleur is not going into high gear.

http://i912.photobucket.com/albums/ac329/hellobikee/0522b34a.jpg

Daveyates
05-27-11, 10:03 AM
I would imagine that you would loosen that screw for more travel because the screw on the other side is to just hold the cable in place.
But first off try to pull the derailleur arm out with your hand to make sure it isn't just very stiff.
thook
05-27-11, 10:10 AM
Yes, that's the screw on the front. But, if you weren't having troubles at one time and have made no adjustments, take the little, plastic Simplex cap off the back end and spray some lube in there. I've rebuilt a couple of those (with no success.....the plastic tube clamp kept breaking) and the mechanism inside tends to gunk up with rust.

Grand Bois
05-27-11, 10:25 AM
Move the shifter to the forward position and take the slack out of the cable. Loosen the set screw and position the cage over the small ring. The screw you're talking is the high gear stop.
zandoval
05-27-11, 11:19 AM
After you it it its painfully simple (Simplex)... These are infact great dérailleurs except for the now aging plastic making them unreliable...
Grand Bois
05-27-11, 12:20 PM
I'm still using one on my Jeunet. It works fine as long as there isn't a large difference in ring size. It's the fancier one with a chrome clamp and aluminum cap that's incorrectly shown on Velo Base as a Prestige. It has another name, but I can't remember it.
randyjawa
05-27-11, 12:23 PM
the now aging plastic making them unreliable...

That aging plastic, Dupont Delrin I believe, was not dependable right from the start. I have seen several bikes in mint shape because the front derailleur broke early in the bicycle's life. And, previous owners reported the failure as the reason for stopping use of the bike.
Grand Bois
05-27-11, 03:08 PM
Delrin is still widely used. There was a huge class action lawsuit after plumbing fittings failed and caused flooding of houses.
thook
05-27-11, 05:16 PM
How 'bout that........hmmm.
finkerbell
05-27-11, 09:28 PM
The Disraeli Gears website has the instructions for the Simplex Prestige 637 derailleur, the last page of which covers the front derailleur and tells how to adjust it.

http://www.disraeligears.co.uk/Site/Simplex_Prestige_derailleur_%28637%29_-_instructions_%281st_style%29.html

See scan 4.