Robert C

As of late I have been using my old Schwinn (made in 84 according to the head-badge, and that sounds about right according to when I remember getting it) for commuting. IN simple terms, I am unhappy about the brakes. They are fine at low speed, but bring it down from anything above 20 is a very slow process.

The brakes are labeled Dia-Comp and the components are all sunXXX. The rims are steel (they will hold a magnet weakly)... yep, theres my problem.

I have looked and I have not been able to find any 27” Al rims to replace them with As it happens, I don't have any bikes with 700s’ siting around. How much bigger, or smaller, are 700s’. The brakes look like I have about 5mm of potential movement in either direction.

Is there a better (cheaper) way to go? Possibly some miracle brake pad?

bikeman715

have you try going to your lbs and asking them to order you a pair of AL wheels? they should be able to order a set around $120.00 from someone like QBP. 700C are a little smaller than 27. if the brake pads reach the rim they will work but it a trial & error way of finding out. the koolstop's salmon color pads made work for you.

Panthers007

Regards brake-pads, check out some Kool Stop. They'll certainly help.

Mr IGH

700C is smaller by 8mm diameter, 4mm is all you need, if your pad drops 5mm you're all set. I've just done this to a Santana tandem and a Schwinn Sports Tourer. Well worth the effort just for the tire selection alone.

peripatetic

It's kind of a toss-up for switching wheel sizes.

27" wheels are usually available fairly cheap at an LBS. My friend just bought a new, generic rear wheel with aluminum rim for $30 plus the cost of the freewheel. If you use your current freewheel and switch over, it shouldn't be too much. A new set of 700c wheels could set you back more. "Only 4mm drop" in your brake pads is sometimes no problem, but when it is, it's a pain. Make sure to check that measurement before switching over.

If you decide to switch to 700c, you will have more tire options, and you can always keep those wheels for a new frame. Sometimes, 700c wheels look kind of funky on 27" frames, though.

You should also make a note of the bb height--it will drop 8mm if you switch frames, which means your pedals/cranks will also drop that much, which can sometimes lead to pedal strike issues.

johnknappcc

What kind of Schwinn, did the 27->700C conversion on mine, with alloy Mavic Open Pro rims/Ultegra hubs. Brakes adjusted (for reach) fine (took two minutes to adjust). It wasn't the cheapest conversion (because I've replaced the most of the drivetrain, still a few more items to go) but I love the bike, and it really is pretty zippy now.



I think they look funky, but only in a cool way.

Little Darwin

The amount of drop depends on tire size that you use on the 700c rims.

If you go with 29er rims and tires (the real fatties) you could actually raise the BB, but these may not fit.

If you use wide hybrid type tires, there may be virtually no drop.

If using the same width tires as with 27" the drop will be about 4mm.

But if you go with narrower 700c, the drop could be 8mm or so.

Mr IGH

Funny to read all the folks weighing in who've never done this...late 70's and up bikes were made with both wheel sizes in mind, esp on the high end because lots of folks would switch to tubular tires from the standard 27" wheels. Even my 87 Santana was set up for 27" wheels with the pads up, 700C with the pads down. Maybe that's why folks that actully try this mod aren't having issues?

Robert C

Here are some pictures of the bike in question





And the breaks
<table style="width:auto;"><tr><td><a href="https://picasaweb.google.com/lh/photo/AaXdLEFpmBjSjOaDW5K3-w?feat=embedwebsite"><img src="https://lh4.ggpht.com/_AS68O8wctBQ/SkkZTLoO54I/AAAAAAAADMY/Zz0esT8lHXo/s144/DSCF0002.JPG" /></a></td></tr><tr><td style="font-family:arial,sans-serif; font-size:11px; text-align:right">From <a href="https://picasaweb.google.com/crawford.robert/Bicycle?feat=embedwebsite">Bicycle</a></td></tr></table>

peripatetic

Thanks for clarifying my misrepresentation. :/

* * *

I've done this on several bikes as I suspect most of the other people posting in this thread have--sometimes it's great, as with the pic above, sometimes not so great. It's definitely not a given that it will look as good or work as well as you hope.

BTW, OP, your pads may need replacing, or at the least, a good filing down to get to fresher material. You might try this as a quick fix for your braking issues.

johnknappcc

Yep, my dia-compe 981 cantis had enough for the 4mm . . . everything was a breeze (it takes me longer to overhaul a hub than it did to make the conversion). As far as BB/crank clearance, I went from 27 1/4" to 700x23's and I haven't noticed any issues.

Robert C

Here are some pictures of the bike in question





And the breaks

johnknappcc

You might need some long reach tektro's but they are cheap . . . but most problems could be solved by moving your calipers in a bit more, and either (replacing) or (cleaning, with sandpaper) the surface of the pads. Rough em' up a bit! We have a bike co-op, and we routinely rough up pads that are still within wear limits. Even on steel rims, we still get pretty good quality (dry) braking. Other than that, move to alloy and you should be good no matter what.

Panthers007

Robert C - off-topic somewhat, but what brand of tires are those on your Schwinn?

Robert C

Kenda, they are like greased roller skates once the pavement is wet; but, they won't wear out and give me a reason to replace them.

griftereck

those look like alloy rims
especially with the brake dust all over the tyres.

I would clean the rims and pads.
set the brake pads tighter to the wheels. tighten the cable.

Pads go hard over the years though. loose there grippiness.

Might be a plan to get new pads.
ones that fit V brakes can be used on sidepull caliper brakes.
and if there longer they will have more pad area to grip with.
normal stores sometimes sell V brake pads for very little.