Bolt Circle Diameter

 

Data from the inimitable Sheldon Brown’s own Bolt Circle Diameter Cribsheet.

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Ring for the Porteur (Part 1)

Porters. You may know the word as a category of dark beer, as a railroad sleeping car attendant or as someone hired to schlep baggage. Let’s French-iphy that a wee bit and apply the definition to bicycles. Frenchiphying it is the easy part: just a “u” after the “e”. Porteur. There. Très bien!

But what does this have to do with bikes? Well, take a gander at this peloton:

It’s a furpiece different than, say this peloton, ya?

You’ll notice that the bikes feature distinctly different handlebars (swept back bars in the B&W photo, drop bars in the color photo) and heavily laden front platform racks in the B&W photo. These bars are referred to as porteur bars and these racks as porteur racks.

Let’s say you want to be like these stouthearted giants and schlep–I mean really schelp–loads and loads of stuff up front where you can see it, touch it, taste it, smell it, then the porteur rack is the way to go.

Coming soon:
This post will be updated with a table of porteur racks including platform size, pannier-ability, material, price, weight and attachment point. Oh boy!
Part 2 (which proves to be more challenging given my limited headspace) will cover commonly available handlebar options.

Photo credit:
1) The super sweet porteur race picture hails across the Internet at, from my reading, the definitive classic porteur alamanc, Blackbird, where site author and historian, Joel Metz has assembled a treat for the porteur obsessed reader to pour over. Specifically, this photo comes from a page dedicated to the 1947 Critérium des Porteurs de Journaux
2) Our second photo is from the 1987 Paris-Roubaix race that I found hosted on Pinterest. Clearly, there’s a better source, but I thought it was a nice shot of the “Hell of the North” back when cycling pros still rode steel frames with quill stems. Specifically, the caption read, “Rudy Dhaenens leads Sean Kelly in the 1987 Paris-Roubaix” but our photographer and original source for this gem is unknown to me.

The State of 650B Rim Brake Compatible Rims

What are the rim brake compatible (non-disc) 650B rims these days? Below is a table of options. Most are made by Velocity (including the below offerings from Pacenti and Soma). I hope this is useful for all of the dozens (literally dozens) of readers!

Make	Model	Inner Width	Outer Width	Depth	Weight	Tubeless Compatible	ERD	Availability	Drilling(s)	Price	Notes
Alex	DM18	18.4mm	24.4mm		520g		569.2mm				silver/black
Alex	X2200	19.0mm	24.4mm		485g		557.1mm				black
Ambrosio	Keba AKA ‘Confrerie’				590g		550mm	limited	36	4,600 yen	double eyeleted, polished
Araya	TX-310F	17mm	23.2mm	14.7mm	520g				36	33.33 €	double walled, eyeleted
Grand Bois	650B rim	17mm	23mm		466g		568mm		32, 36	$ 98.00	silver
HED	Belgium Plus	23mm	25mm	24mm	462g	Y			28, 32	$ 150.00
Pacenti	Brevet	19mm	23mm	15.0mm	430g	Y	574mm		28, 32, 36	$ 98.00	silver
Pacenti	PL23	18mm	23mm	15.5mm	454g	Y	573mm	OOP	28, 32, 36	$ 90.00	black, silver
Pacenti	SL23	20.3mm	24.5mm	26mm	420g	Y	550mm	OOP	28, 32, 36	$ 104.00	black, silver
Ryde	ZAC 421	21mm	28mm	22mm	605g		567mm	Ryde	32, 26		black, silver
Soma	El Nino 24 Rain Rim	19.9mm	24.4mm	16.1mm	540g		565.8mm	Soma/Merry Sales	32, 26	$ 89.99	eyeleted, grey hard anodized
Soma	Weymouth	19mm	24.4mm	16.1mm	540g		565.8mm		32, 36	$ 59.99	polished
Sun	CR18	18mm	22.5mm	15mm	505g		574mm	limited	32	$ 33.00	silver
SunXCD	Randonneur	17mm	22mm	19.2mm				coming soon	32, 36		silver
Velo Orange	Diagonale		25mm		550g		570mm		32, 36	$ 69.00	double walled, polished Al with steel eyelets
Velocity	A23	18mm	23mm	19.5mm	425g	Y	562mm stated / 568mm measured		32, 36	$ 90.99	black, silver, polished
Velocity	A23 O/C	18mm	23mm	19.5mm	435g	Y	560mm stated / 568mm measured		32, 36	$ 96.99	black, silver, polished
Velocity	Atlas	19.8mm	25.4mm	18mm	590g		569mm		32, 36	$ 87.99	silver, polished
Velocity	Cliffhanger	25mm	30mm	20mm	625g		558mm		32, 36, 40	$ 90.99	black, polished, reflective
Velocity	Dyad	18.6mm	24mm	22mm	495g		560mm		32, 36	$ 78.99	black, silver
Velocity	Synergy		23mm	18mm	490g		567mm	OOP	28, 32, 36	$ 64.95
Velocity	Synergy O/C		23mm	18mm	490g		567mm	OOP	28, 32, 36	$ 64.95
Velocity	Twin Hollow		22mm	14mm	480g		576mm	limited	36	$ 41.99	silver
Weinmann	ZAC-19						564mm	unknown

Measurements above are given in millimeters and grams. Pricing may vary, prices given above are base prices from the Interwebs. Some of the polished Velocity rims are $30 more. Specs subject to change. I try to get this right, but am held harmless in the event of error. Should an error occur, please notify me.

If I’ve missed anything or if you can fill in the gaps above, please leave a comment and I’ll incorporate it into the table.

I will be updating the table to include Tubeless Compatibility

650B Conversion Tire Clearance Repository

What bike(s) have you converted to 650B? What tires fit?

Make	Model	Year (or era)/ serial number/ distinguishing feature(s)/ color	Frame Size	Largest 650B tire that fit (stock)	Try anything that didn’t fit?	Brakes used to convert	Other comments	Contributor
Centurion	Turbo	1983	58cm	Col de la Vie 38mm	fenders	Tektro R559		Rory!
Katakura	Silk	Full chrome, ca. 1984	61cm CTC	38mm with fenders	none	Tektro R559	Easiest conversion I’ve ever done…this bike fit the tires/wheels almost as though it were designed to do so. Fork was medium trail though.	Azorch
Nishiki	Comp II	1986	56cm	42mm		Tektro R559		Bruce
Torelli	from Cinelli Corsa factory	1983-4	57cm	38mm	Too tight to safely run 42s	Tektro R559		Bruce
Trek	420	1989	58cm	42mm	fenders	Tektro R559 (maxed out in back)	Here is a slightly older one that fits Hetres & fenders: http://brazenbicycles.com/Trek-650b-Town-and-Country Also this looks like a 1986 400: http://brazenbicycles.com/Trek-400-650b-Sport-Touring	Rory

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Have you converted a bike? Comment below with the following and I will update the table:

1. Make
2. Model
3. Year (or era)/serial number/distinguishing feature(s)/color
4. Frame size
5. Largest 650B tire that fit
6. Any 650B tire(s) that you tried that didn’t fit
7. Brakes used in conversion
8. Other comments

 

Tire Size and Air Volume

 

Wheel	Tire	Volume	Increase over 700x23C	Example Tires
700C	23mm	3.5 L	0%	The old standard
700C	19mm	2.4 L	-33%	Oh, dear!
700C	21mm	2.9 L	-17%	Eek!
700C	26mm	4.5 L	29%	Grand Bois Cerf Blue (222g, 184g), Compass Cayuse Pass (248g)
700C	27mm	4.9 L	39%	Challenge Parigi-Roubaix (285g)
700C	28mm	5.3 L	50%	Compass Chinook Pass (229g)
700C	30mm	6.1 L	74%	Challenge Strada Bianca (355g)
700C	32mm	6.9 L	99%	Compass Stampede Pass (291g, 254g)
700C	33.333mm	7.6 L	117%	Jack Brown (435g, 295g)
700C	35mm	8.4 L	140%	Compass Bon Jon Pass (355g, 303g)
700C	38mm	10 L	185%	Compass Barlow Pass (390g, 359g), Soma C Line (400g)
700C	42mm	12.3 L	252%	Soma Supple Vitesse (380g, 340g)
700C	44mm	13.6 L	289%	Compass Snoqualmie Pass (378g, 329g)
700C	50mm	17.8 L	411%	Schwalbe Marathon (1.0T)
700C	55mm	21.9 L	527%	Schwalbe Marathon (1.125T)
650B	32mm	6.6 L	88%	Hutchinson Confriere (320g), Grand Bois Cypress (285g, 261g)
650B	38mm	9.4 L	170%	Compass Loup Loup Pass (354g, 333g), Panaracer Pari Moto (340g, 300g)
650B	42mm	11.6 L	233%	Compass Baby Shoe Pass (390g, 362g), Grand Bois Hetre (412g)
650B	48mm	15.5 L	343%	Compass Switchback Pass (478g, 413g)
26″	32mm	6.3 L	81%	Compass Elk Pass (178g)
26″	38mm	9.1 L	159%	Compass McClure Pass (366g)
26″	44mm	12.4 L	254%	Compass Naches Pass (350g, 300g), Compass Slumgullion Pass (447g)
26″	50mm	16.3 L	366%	Schwalbe Big Ben (1.5T)
26″	54mm	19.2 L	450%	Compass Rat Trap Pass (454g, 418g)
26″	55mm	20.0 L	473%	Schwalbe Big Ben (2.0T)

Air volume was calculated in MS Excel with the following formula (this example is for 650B/584ISO with 38mm tires):

=2*PI()^2*(584/2+38)*38^2

This will give results in cubic millimeters. Volumes above have been convert to liters (dividing by 1 million), rounded to the nearest tenth.

Some variances may be introduced from rounding, unit conversions, and other factors.

This is all white coat, clean room, armchair nerdery stuff only. Real life measurements of tires can vary based on many factors including miles, rims, tubes, production batch, etc.

Tire weights are manufacturer published weights, except for Schwalbe which were 100% fabricated for my own amusement.

Sources:

https://en.wikipedia.org/wiki/Torus

http://www.metric-conversions.org/volume/cubic-millimeters-to-liters.htm