SD Fixed

I picked up (likely an overpriced) Univega for my daughter, it's pretty big for her, but it has the "female" sloping down tube. Probably late 80's or early 1990's. It's a project for both of us to work on. I've noticed it's got some really good drop outs (suitable for a fixed gear... likely not anything we're gonna do) that have screws in rear for some manner of adjustment.

Why do they have this, i.e. what purpose do they serve? Merely something to hold it in place? How important are these to be in lining up the rear derailer?

roadfix

You can fine tune your wheelbase distance.

sch

Most of the 20th century bikes were made with "horizontal" (actually downsloping a little) rear dropouts and the wheel axle was set in the slot by eyeballing the tire between the chainstays for centering. A few dropouts, usually higher end ones, had little, fragile screws that were used to locate the axle in the fork
with instant indexing so you didn't have to eyeball the tire for center placement. Wheel was pulled back til both sides of the axle butted against the screws. Vertical dropouts are now universal and they index the wheel axle automatically in the top of the slot everytime. Steve

roadfix

Hey Fixer,
Now what kinda bone head statement is that???!!! Frame size and geometry determines the wheelbase!!

George

froze

Most derailleurs are set up to perform the best when the wheel is placed in the forward most position in the dropouts, the quick-release should not be hanging out in space, but it should be fully in the front of the dropout. Make sure you center the wheel in the frame, with equal clearance between the rim and the chainstays down behind the bottom bracket. Then run the adjusters up against the backside of the axle. The next time you put in a wheel, the adjusters will have “remembered” your setting, and you won’t have to monkey around with centering the wheel again unless the adjusters move.

Also you can change the handling and the ride characteristics just a tad by moving it back the max, usually 7 to 9mm; but you may have to readjust the derailleur depending on the chain tension.

SD Fixed

Ahhhhh... suddenly it all makes sense!!!

Fixer: that's why you ride fixed, right?

froze

I'm a little confused, is Fixer having an indentity problem?
Why does "Fixer" say "hey Fixer" to himself in the 2nd post? And who's George that signed at the bottom of "Fixer's" 2nd post but not the 1st? Is this a Troll that migrated from the "other" bicycle forum?

roadfix

I was reprimanding myself......instead of simply editing or deleting my original post...that's way too easy. Now, of course, the honorable thing for me to do was to commit harakiri.

George (Fixer)

gruppo

Hey Fixer,
Regarding "Priceless", how do you keep everything together without using spoke nipples (Do you not use them 'cause you might drop some in the glass of wine you're working over)?
Happy Holidays,
Gruppo

roadfix

Ah...good point. Brass nipples are included with the price of spokes. Have a safe New Year's.

George

froze

Well then an apology is in order from me! But please don't commit harakiri, because I'm sure dentist everywhere love those unusual teeth!

dexmax

I have managed to loose these small screws a couple of times before.. So what I did, I screwed it in.. glued it in place, and cut the screw head to save weight...

sometimes I just laugh at my stupidity... The good thing is.. I don't have to reallign it anymore...

New frames don't have these anymore.. thank god.