old's'cool

To clarify, not all rims are offered with both valve size drillings. But many are. Even rather noodly Rigida 1320s have come into my possession, I have no reason to doubt in factory condition, with Schraeder valve holes. I don't think the difference in strength or stiffness between a Presta and Schraeder size valve hole is a big concern.
But yeah, just because you have Schraeder tubes on hand isn't a good reason to drill out your rims. I've done it to match front and rear wheels; that's probably not a very good reason either.
More and more, I'm standardizing on Presta tubes, so my mini pump will work on any bike, any time. So I just put bushings in the rims that are drilled for Schraeder tubes.

fuji86

SkyDog75, for some reason though the compression of the spring and lever operation just feels like I need more force on the lever handles than what was required for the wider rims. I feel better now that I read your post.

As for 700c brake calipers, I meant a modern brake caliper, something more aero than the Dia Compe's of the 1980's that I have. Today's bikes usually have a rim suited for a 25 or 28 aero rim. The last bike I adjusted calipers for, was a SS/FG with 700x25c tires & aero rims on it and the rim looked 1:1 for rim & tire width, there was virtually no squeeze required to adjust them to compress the spring. Like the caliper was made for a tighter/narrower rim. This adjustment on the Dia Comp calipers from the 1980's seemed like the spring was much harder to compress because the spring travelled further. Like I had somehow neared exceeding a maximum compression the spring would do and was worried that it would even be worse as the pads wore and perhaps needed further adjusting. Outside of the vintage road bike & SS/FG I have a vintage atb and a disc brake MTB, the atb doesn't have side pull caliper rim brakes. Those I believe are post mounted cantilevers. Been awhile since I adjusted rim brakes on any bikes that I have. The disc brakes on the MTB are hydraulic disc, so that will be a matter of burping & bleeding.

SkyDog75

In theory, it'll take a little more effort since the caliper's spring will be more flexed, but I wouldn't expect enough of a difference to notice at the lever. If you do notice a significant difference in lever resistance, I'd suspect something like excess friction somewhere -- maybe a kinked cable inside the housing, a too-tight curve introduced if you re-routed cable, a pivot nut/bolt you might have adusted... pretty much anything but the caliper's return spring.

To get to the point: Don't worry about the return spring and don't worry about the rim's width. Those are both non-issues. If there's a problem, we'll find it elsewhere.

The vast majority of decent new caliper brakes are dual pivot brakes, which do have a different feel. Even inexpensive Tektro dual pivots are good, stiff-armed brakes and I like 'em a lot compared to most single-pivot brakes.

Since you mentioned Dia Compe in particular... Like many companies, they've made a range of products, some better than others. The Dia Compe Q500N brakes that came on my '86 Trek 300 Elance were on the lower end of their product range and I hated those brakes. Not quite ex-wife levels of hatred, but close. Both seemed to want me dead. Even with new pads, those things didn't stop worth squat and they had a really mushy feel. Spending $30 on new dual pivot brakes was one of the best bang-for-the-buck upgrades I've ever made to a bike.

fuji86

Just got up after reading your post to look at the brake calipers on my SS/FG, they are dual pivots. And the bike I have is more a mid-level Fuji from 1986, but you're right on the brakes that are original on the bike that I'm still using. They aren't the highest end components, but they still work and I'll continue to use them.

I rode a metric century on the wheel set today to break them in. The brakes & pads seem to have also seated in with the new rims and any adjustments I made. That or I got used to them and trust them more now with a longer & challenging ride than around the neighborhood ? I thought I was doing pretty good for speed, I was moving at between 20.7-21.2 mph on a stretch according to the computer. Some punk on his carbon bike came out of nowhere and smoked me. I was about 45-48 miles into my metric century, so I wasn't exactly fresh, The front end of the ride was into a gusty headwind too, but that's not really an excuse he dropped me and I was just trying to maintain a steady average speed & cadence. I would've needed to have the same tailwind without the work I had done to try to match him fresh. I figured he parked in one of the State parks in the area like so many cyclists do, they drive their bikes to where they ride. Even when I MTB I've put in 10 miles on asphalt to get to the greenway/trails. So, 20 miles on an MTB is a significant chunk of any trail riding.