tatfiend 

What is the attraction of converting a bike to 650B wheel size? If it started life as a 700c or 27" wheel bike then the conversion requires installing much longer reach brakes and the bottom bracket height is lowered by about .75" or a bit more unless the tire width fitted is greatly increased.

I can see possibly converting 26 x 1 1/4 (597mm BSD) and 26 x 1 3/8 E.A.3 (590 BSD) bikes to 650B for better tire selection and availability though I understand 650A tires are even more readily available.

stien

I believe 650B is for those who want much bigger tires than the 700c or 27" can let them run without hitting the frame.

ColonelJLloyd 

That's my take. Converting to 650B will allow you to run a much larger tire (lower pressure, more comfy) while maintaining a comparable circumference.

bobbycorno

...and what's wrong with lowering the bb? And don't bring up the old "pedal strike" argument: In 35 years of riding (including 15 years of USCF racing) I've caught pedals on the pavement maybe half a dozen times, the last one was um.... let's see.... 15-20 years ago. And that includes a lot of miles on a bike with a 10" bb height and 180mm cranks.

SP
Bend, OR
ps - going from a 700x23c to 650x38b (probably the most common conversion) will drop your bb 5 mm (< 1/4"), not 3/4".

Mike Mills

I think the attraction is to mount fat tires to the bike. Brake arm reach is a low hurdle to overcome. A high hurdle (true limitation) is frame clearance.

I am researching and searching for a C&V or C&V-type frame that is both lightweight and can accomodate fat tires (2.5" wide). The objective is comfort. Wheel size is unimportant but 26" is probably my minimum. Right now, I have found almost no suitable frames.

Omiak

Fenders.

bobbycorno

A man after my own heart. A "racer boy" bike may look ok w/o fenders, but one that's fender-capable just looks goofy without 'em.

SP
Bend, OR

tcs

An ISO23x622 (700C x 23) and an ISO42x584 (650B x 42) are going to be pretty close in outside diameter, depending on how the tire fits on the rim & etc. One can run a lot chubbier tires without changing the geo., so there's your conversion, right there.

Additionally, an ISO38x622 (700C x 38) tire on a hybrid or city bike starts to be pretty large in outside diameter to use in a well-fitting, good-handing small frame size bike design.

IMO a standard, available size around about this dimension makes sense.

A charge card will get you any of these 26 x 1 3/8 tires either in your hands or on order today:

Bell Sports Streetster (folding)
Chengshin C638
Continental City Ride
Kenda gumwall
Kenda Cross (knobby)
Kenda K40 Street
Michelin World Tour
Nutrak Traditional
Nu-teck (airless)
Panaracer Col de Vie
Panaracer ST Daily Commuting
Pyramid gumwall
Pyramid Sunlite Hybrid Nimbus
Raleigh Record
Rubena Flash V66
Schwalbe Delta Cruiser
Schwalbe Marathon
Schwalbe Marathon Plus
Schwalbe Speedway Pro (knobby)
Specialized TriSport
Vredestein Perfect Tour

Funny thing about tire availability: Let's say you're a cycling retailer. Carry 27" tires, even though they're obsolete? Sure, because a 1 1/4 inch wide one is going to work on 99% of the bikes owned by crusty old guys who come in looking for a 27. Stock the old, obsolete 650A? Sure, because they're all 1 3/8 inches wide, so just pick one you make good margin on and it's going to work on 100% of the bikes that use this size. The inventory will turn. 700C? Sure, of course, industry standard and all, but what widths? 19, 23, 25, 28, 32, 35, 38, 42, 47, 54, or 62mm? Inventory nightmare! Then we come to the 650B: an rare tire diameter that additionally comes in 28 to 57mm widths. Stock a 44mm and the only guy in three months that wants one will want a 37mm!


tcs

nlerner

As others have said, the attraction for me was to fit plush tires and fenders on a bike made for narrow tires w/ no fender clearance. I've got two conversions in the fleet right now: a 70s St. Etienne that's my porteur and a '87 Trek 330 Elance road bike. I also have a 650B-built Ebisu. The tire choices are actually pretty wide right now, and more important to me, several tires are about the nicest I've ever ridden. Those include the Grand Bois Hetres (41mm), which I have on the Ebisu; the Pacenti ParoMoto (38mm), which I have on the Trek; and the Grand Bois Cypres (32mm), which I used a lot on my departed Kogswell. On the St. Etienne, I ride the Panaracer Nifty Swifty, which I like a lot. I've also had Panaracer Col de la vie tires on a few different conversions over the last few years, and they're a great bargain at about $20/tire. Several other tire options exist, including Schwalbe Marathon and a bunch more that seem fairly heavy and low end, but I don't have direct experience with them.

One of my favorite 650B conversions was a '78 Raleigh Competition GS. I found the wider tires (Col de la vies on that one) took a somewhat harsh riding bike w/ racier geometry and really smoothed it out for both comfort and speed. Another project I'm hoping for a similar result is to convert a Vitus 979 alu frameset.

As in all things, ymmv.

Neal

noglider 

Other than adding fenders or fat tire to your beloved tight-clearance road bike, I think the new 650B trend is a lot of hype. I can't remember where I read it, but there was an article about how 26" (559mm) wheels are too small and 700C wheels are too big, and 650B is just right, with a luscious yet still efficient ride. Give me a break. You can make changes a lot easily by changing tires.

nlerner

Tom, all I can say is, Try it, you'll like it!

Neal

embankmentlb

Conversion is the key word.

noglider 

Neal, how would you describe the ride?

nlerner

Tom, definitely "luscious but still efficient." Actually, I have no idea what that means, but I find that my 650B rides in general have lots of cush and roll right over rough spots in the road, but the good quality tires means that they still feel fast-ish, so it's not like riding a balloon tire Schwinn.

Neal

Grand Bois

The only reason I haven't tried it is the expense of rims, spokes, tires and brakes. I'll bet that Rivendell has made a fortune on 650B conversions.

ewmyers

Hi Neal,

So are you saying that it is primarily the available tire quality that makes the difference between the feel of the ride on 650B vs 26" wheels? You would be happy, say, putting better quality tires on your balloon tire Schwinn, as opposed to doing a 650B conversion on it? Not arguing, just trying to understand.

Thanks,
Eric

nlerner

Eric, I think that's close to true for me, but a balloon-tire Schwinn is still a heavy beast no matter the tire. The best 650B conversions I've done are on lightweight road bike frames w/ "racier" geometry.

Then again, Matthew Grimm, creator of Kogswell, has declared he's done with 650B and is developing new frames designed for 559mm wheels, which he feels are *his* sweetspot!

Neal

Mike Mills

Exactly so!

This is the "problem", frames that are designed for the fat tires tend to be heavy, dead clunkers.

Frames that are light and lively tend to be designed only for skinny, skiny 700c tires. The sweet spot (for me) is a light weight, high quality rigid (non-suspended) mountain bike frame. The frame geometry is more relaxed and confortable. The fat, high pressure tires give all the "suspension" you'll need on a paved road. There's plenty of room for fenders. There's braze ons for racks, if you want them, too. The riding position is somewhat upright but forward enough to be energy efficient and fast. Light weight, aluminum rims, and powerful cantilevered brakes, triple crank up front, indexed shifting,... what's not to like?

That last question is not just rhetoric.

noglider 

And Velo Orange, too. They play up how the wheels are the bee's knees because they can sell stuff that way. I have a hard time believing they are a magical sweet spot.

I'm putting super narrow tires on someone's mountain bike today. I'll see how it feels.

Grand Bois

It will probably feel zippy compared to a mountain bike with fat knobby tires, but still slow and heavy compared to a decent road bike. That's why my MB-2 with skinny slicks is gathering dust and cobwebs in the rafters.

Mike Mills

Gentlemen,

The two versions you mention are well outside "the sweet spot". I suspect you are well aware of this. ;-)

Super-narrow slicks on a mountain bike will ride as harshly as they do on a road bike. Fat, knobby tires on a road bike will be as rough, noisy and sluggish as they are on a mountain bike or beach cruiser when ridden on a paved surface. Those versions are outside the desired envelope.

What's being suggested is to use fat, high pressure slicks (or lightly treaded) tires on a zippy frame. Because most road frames will not accept fat enough tires, many have opted for smaller diameter wheels. What this does is move the point of maximum tire width (not tire height) to a smaller diameter, thereby gaining additional clearance from the frame.

What would be cool is to compile a list of bikes which are available set up this way. Another cool list would be of frames compatible with this set up.

nlerner

Lots of good stuff from Ed Braley, the guru of 650B conversions on "fast" bikes:

https://www.bikeman.com/content/view/1771/146/

https://650b.webs.com/conversions.htm

https://www.bikeman.com/component/opt...0B/Itemid,135/

Pics of Ed's fleet:

https://www.flickr.com/photos/25373440@N00/sets/

Neal

noglider 

I have a Surly Cross Check which accepts extremely wide 700C tires. Are cyclo cross bikes that hard to find? I'm under the impression that the Cross Check is pretty close to a classic cyclo cross design.

mickey85

I'll say this about fatter tires and smaller wheels, then duck back out of the way. Currently, the two bikes I ride regularly are a 590 wearing Phillips 3 speed and a 630X28 Fuji Palisade. COmfort-wise, the Phillips beats the Fuji every day. The Col de la Vies that I have on it are like riding on pillows. Then again, I've got 40psi front, 55psi back, so they're pretty low pressure-wise. The Fuji with it's 100psi 28's (100 front, 110 back) ironically doesn't seem to roll as well, and it picks up road buzz more easily, but I feel that it corners much more effectively, and is much easier to control in dirt or other at-the-limit riding (God knows, with the 'rents living on a dirt road, I see that enough).

I would truly be interested to see differences and similarities between 584/590 and 622/630 on an identical bike.

mickey85

I've got one bike now that was listed as a hybrid, but has CX geometry that fits 38's, and two more that originally wore 27X1-1/4 tires that have such huge reaches that it would literally be impossible to fit 650b on them due to brake reach. Either of those could easily take 40mm 700c tires. But then again, those are pretty low end (UO-8 and Raleigh Rapide mixte).

Got a World TOurist also that could probably take 35-38's...

ETA: Something else to consider...what would the weight be of a pair of 650b wheels and good tires (hetre, CdlV, etc) compared to 700c wheels and comparable tires? I know the 700X38's I was riding on the CX/hybrid nearly killed me after about 10 miles because they were so bloody heavy and resistance crazy. I could triple my distance at a given speed switching from 38's to 28's on the same bike with the same wheels.