Just put the new wheels on and raise/lower brake pads on the clipers as necessary?

Provided there is frame clearance, is it as easy as that?

I doubt your brakes will have that much adjustment range. What's wrong with 650b? A lot of folks do the conversion the other way, from 700c to 650b, just to get more clearance for fatter tires and fenders. To do that they need to change to long-reach brakes or fabricate a drop-bolt.

It's a catch-22. If you have enough clearance for a 700c wheel, then it's almost certainly a Canti or V-brake bike. In that case there's not nearly enough travel and you need one of those adapters Mavic used to make until about 5 years ago.

There are a few V-brakes made that have the latitude to move the shoes high enough, but they're pricy and when you move the shoes that far it changes the geometry enough that performance is way (really way) below par.

I did the conversion in question. My utility bike, an early 80s Schwinn Mirada came with 650b rims. The rear was badly bent beyond trueing. Replacements were not cost effective. Picked up a set of 700c rims. They fit, but can't go beyond a 32 on tires. The brakes sorta work. The pads cannot be raised quite enough. It stops good enough, so I haven't screwed with it any more. Wish I could have found a set of alloy 650b rims to replace the stock steel set.

If you want a smaller tire why not convert to 650c?

I know https://www.icyclesusa.com/ is temporarily closed but they did have some 650b rims for cheap at one point. And their shipping cost to Canada was cheap. Maybe you could wait until they're online.

It can be done. Really depends upon the exact bike-model in question and how it was design and built. A lot of 650b bikes started life as 700c and can be converted back easily. Post pictures of your bike with measurements of the following areas:

1. fork-crown to tyre-clearance
2. front-brake, side view of pad-position
3. front-tyre to downtube clearance
4. rear brake-bridge to tyre-clearance
5. rear-brake, side view of pad-position
6. rear-tyre to seattube clearance

If you've got 19mm of clearance and adjustment in these areas, it is a simple swap to 700c wheels. Otherwise, you may need to do some cutting & re-brazing/welding. Similar to converting 700c road-bike to cyclocross or a 26" MTB into a touring-bike (adding/removing cantilever posts), maybe change forks. Not that daunting, I've done quite a few.

I don't have one yet, but I am scouring the planet looking for either a Rivendell Bleriot or Rambouillet or Saluki. Or a cheap Homer Hilsen or Roadeo. I don't have the privelidge to go on the Wanted forum here. So I try Clist and eBay.

The Saluki and Bleriot are 650b. I would leave them alone unless there was a reason later for going to 700. That is why I was wondering if it is easy or not. But I would just leave them as 650b unless.

Man, looking for boutique 650B bikes, with the intent of converting them to 700C. Anyone ever tell you that you like to do things the hard way?

You could go to 650a (26x1-3/8) ISO 590 really easily. Sun has some CR-18 rims in that size.

Good point. This is a grab-n-go ride anywhere hackback. It would have been more cost effective to replace it with another cheap MTB or hybrid than to bother with building wheels. I picked up a nice set of 700c rims for $75 and fitted $8.00 tires. The Schwinn works better than it should.

I loved the 650b concept. Cost is the biggest factor. Wish I could find a set of 650b disc mountain bike rims for my Nashbar bike. They'd fit with 40 Panaracers.

+1
Given their boutique nature, do 650B bikes (of average grade) carry a price premium. Could you sell off your bike and pick up a properly dimensioned 700c or 26MTB modern spec bike.?

650b craze run its course? seems like there were conversions the other way
just a couple years ago.

those sold a few longer reach Tektro dual pivots.. to accomplish.

now I suppose the race short reach calipers get used..

Actually there's a concerted movement to re-introduce and mainstream this size. Just what we all need more standard sizes out there, so that much more inventory will be needed for the same number of bikes.

Not sure what the benefits of 650b are other than making smaller bikes more proportional. At 50-52cm sizes, you can't pull in the wheels tight enough to shorten the wheelbase due to minimum chain-stay length (tyre touches seat-tube). Pulling in only the front-centre causes too much weight on front-end and you also end up with too much toe-overlap. Standover height is still high due to minimum head-tube length. At those sizes & smaller, I'd just build a frame around 559mm MTB wheels. I've seen a couple of these frames in 46cm and they're quite cute! Plenty of road rims and tyres available in that size.

It should be obvious to anyone who's been involved with bikes for a number of years. There aren't enough new entrants to this sport to support the volume the manufacturers are used to. So they have to keep re0nventing the wheel bringing out NEW stuff different enough that that they can hype it as better by enough to get folks to replace existing working bikes and feed the monster.

Expect lots of press about the virtues of 650b vs. the current 26 x 1.xx size.

Ah, I see. "New and Improved".

ftfy