650B is NOT 27.5"

[Eldron]

Okay so I posted this before but damnfangle man I'm tired of people referring to 650B as 27.5" or halfway between 26 and 29.

 

It aint!

 

Here's the low down:

26 diam = 559mm

650b diam = 584mm

29 diam = 622mm

 

So 650B is only 12.5mm bigger than 26" in radius. Not a lot.

29" is 31.5mm bigger. Also not a huge amount but nearly 3 times the amount of 650B.

 

Yes I know it's not a bit difference but everybody seems to be jumping onto the 26 for small, 650B for medium and 29 for large bikes rule and it simply aint true.

 

In my opinion 650A would have been a better "standard" to settle on.

[jimmy hardtail]

So 12mm radius increase. That's 4%? How much of a difference can it make?

[Jigghead]

OK, so here's my ignorance shining through, what is the 650 for? And what is the 'B' for?

[Eldron]

So 12mm radius increase. That's 4%? How much of a difference can it make?

 

That pretty much sums up my entire opinion of 650B - why bother? Too many people get caught up in the "magic" of 29er or 650B without actually knowing what they're buying.

[Eldron]

OK, so here's my ignorance shining through, what is the 650 for? And what is the 'B' for?

 

For your enlightement eager one:

 

650[Letter]

In the French sizing system, tires are designated by a three-digit number, which may be followed by a letter. The number is the nominal outside diameter of the tire the rim was originally designed for. The absence of a letter indicated a narrow tire; "A", "B" and "C" indicated increasingly wider tires."A" was originally a tire about 30 mm wide, so the 650A rim is pretty large, 590 mm. If you add the top and bottom 30 mm tire thickness to 590, you wind up with the 650 mm tire diameter.

 

The 650C size was originally intended for a quite wide tire, about 40 mm wide. Top and bottom 40 mm tire plus the 571 mm rim size again bring you to a 650 mm outside diameter, even though the rim was smaller.

 

With time, however evolutionary processes have led to different widths of tires being applied to the rim, so the nominal 650 mm designation is now more theoretical than practical.

 

•597 mm, 650, is the same as the British 26 x 1 1/4" size used on club bicycles, and was also adopted by Schwinn for use on 3-speeds with a 1 3/8" wide tire. This size is seen less and less, as the bicycles which use it become rare.

•590 mm, 650A, also called 26 x 1 3/8", is the size used on the classic English 3-speed. There's nothing theoretically wrong with this size (other than confusion with the Schwinn size!), but the selection of tires and rims available for it is pretty scanty these days.

•571 mm, 650C, was originally a wide, balloon tire size, used on many older Schwinn cruisers. These days, however, it is mainly seen on triathlon bikes and time-trial machines. Available tires and rims are mostly very narrow, intended for competition use.

•584 mm, 650B, is the focus of this article. This size, also known as 26 x 1 1/2", is most popular in France, where it was the traditional size for loaded touring bikes and tandems, as well as general utility bikes.

The 650B size was never common in the U.S., and it went into decline even in France with the advent of the mountain bike. However, there is a dedicated group of fans of this wheel size, who have been diligently working to restore it to its former glory.

 

The situation as far as tire and rim availability has lately taken a turn for the better, and the future looks rosy for 650B.

[Wyatt Earp]

Take a 700c rim ,slap a MTB tyre on there and we have 29 " (or near damn close)

Take a 650 B ,slap a MTB tyre on there and we have 27.5 " (or near damn close)

[Dirtbreath]

If you're quick you can be the first to do a real 27.5" and can market a whole new bike. You'll make millyuns!

[jcza]

Is 29" not equal to 700?

 

EDIT: thx dangle just saw your response

Edited November 13, 2012 by jcza

[G-Unit]

That pretty much sums up my entire opinion of 650B - why bother? Too many people get caught up in the "magic" of 29er or 650B without actually knowing what they're buying.

 

Couldn't agree more. There's only 1 place where 12mm extra would really make that much difference...

[MrJacques]

Agreed, 650A would have been the in-between size. Maybe we will see it emerge in a few years when they need to sell more bikes. As it stands I'm tempted by 650B, but the difference doesn't seem enough for me change now. If my bike breaks I would go for a 650B FS though. (Or 650A if that's available...)

[Vetseun]

I battle to understand why some people are so sensitive about the whole 650b thing. If you want to ride one flippen ride one. Nobody is forcing anybody to ride the farking bike! If you want to ride a 26" ride it! If you want to ride a 29" ride it and if you want to ride a 650b ride the bloody thing. You have to ride it, nobody else. But some people have to give thier inputs to slate it. I ride a 650b and I enjoy it, I also ride a 26" bike and I enjoy it too and what the hell, maybe I will buy a 29er too and enjoy it too, it is my choice. Climb on your bike, stop bitching and ride it!

[Shebeen]

Okay so I posted this before but damnfangle man I'm tired of people referring to 650B as 27.5" or halfway between 26 and 29.

 

It aint!

 

 

halfway in diameter != halfway in circumference. 650B could be the prefect inbetweener(i don't know this, but if you understand pi then you'll get my drift.) mm ,did someone say pie, where?

 

edit: I've rethought my idea, and it would make more sense for 28" to be halfway between 26 and 29.

Edited November 13, 2012 by The Dictator

[Eldron]

Take a 700c rim ,slap a MTB tyre on there and we have 29 " (or near damn close)

Take a 650 B ,slap a MTB tyre on there and we have 27.5 " (or near damn close)

 

Oi Dangle - you of all people should know that is not true.

 

700c/29er rim with a 2.1 tyre gives you about 27"

650B rim with 2.1 tyre gives you about 25.5"

[Wyatt Earp]

Oi Dangle - you of all people should know that is not true.

 

700c/29er rim with a 2.1 tyre gives you about 27"

650B rim with 2.1 tyre gives you about 25.5"

 

I have measured the stuff myself.

The 29 and 27.5 is the measure you get from edge to edge of tyre.

[MTBc]

so its sort of like a medium?

[jcza]

I think I must leave this thread - I'm even more confused now. I thought 700 comes from road bikes