Author Topic: 26in or 27in bike choice  (Read 5883 times)

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Offline thomasclarke

26in or 27in bike choice
« on: March 24, 2005, 06:53:59 pm »
Can someone please explain the pros and cons
with regard to choosing a loaded touring bike
...ie Bruce gordon BLT...thanks


Offline RussellSeaton

26in or 27in bike choice
« Reply #1 on: March 24, 2005, 10:50:23 pm »
With regard to rim diameter only.  The 26 inch mountain bike size tire is 559 mm bead seat rim diameter.  The 700C racing bike, touring bike, etc. is 622 mm bead seat rim diameter.  These are pretty much the common current wheel sizes on new bikes in the USA and Europe.  Not sure about the rest of the world.  Recumbents and folding bikes, etc. may use other wheels.

There are a multitude of tires available almost everywhere for either size, 26 or 700C.  Anything from 1" to 2" can be found for both rim sizes.  But 26 is usually easier to find in more places.  Wal-Mart sells 26 tires.  But they do not sell 700C tires.  I'm not advocating you buy your tires at Wal-Mart but if you are in a town that does not have a bike shop and you need a tire, the 26 will be much easier to find.  I also think the 26 mountain bike craze has infested the entire planet more than the 700C racing/touring bike has.  So in deepest, darkest Asia or Africa, you are more likely to find 26 size tires instead of 700C.

As for wheel strength, 26 is stronger than 700C.  Enough to matter?  Not for well built touring wheels with 36 spokes and durable rims.  Either is strong enough.

If I were ordering one of the Bruce Gordon bikes and had the choice of 26 or 700C, as he provides, I would choose the 26.  Mainly for the easier tire finding ability everywhere in the world.  And hopefully his bikes are built so they can take up to 2" wide 26 tires so you can use the same bike with knobby tires on the worst roads of South America, Asia, Africe and with 1.25" slicks on paved roads in the USA/Europe.  With a 700C size, you probably do not have the clearance for extremely wide 2" knobby tires for the worst roads.  So you would have to use the 700C touring bike for tours on paved roads and the 26 mountain bike for touring on unpaved roads.  Having two different touring bikes is not a bad thing.


Offline thomasclarke

26in or 27in bike choice
« Reply #2 on: March 25, 2005, 12:08:20 am »
thank you very much for the informative reply.
do not seem any big disadvantage in going with a 26.
I appreciate your insight.


Offline RussellSeaton

26in or 27in bike choice
« Reply #3 on: March 29, 2005, 03:52:31 pm »
About the only disadvantage to 26 mountain bike size tires is they will look small when you use the 1.25" or so slick tires for touring on good paved roads.  It will look like you have a kid's bike, not a real adult bike.  The 26 mountain bike tire is really only 26" in diameter when you get the 2" wide knobby tires.  The skinniest slick tires are around 24" diameter.  So your bike looks different.  Obviously not a big deal.

The 26 mountain bike size rim is 559 mm bead seat ciameter.  559/25.4 = 22" diameter for the rim.  Wide knobby tires are about 2" tall as well as 2" wide.  So you get about 26" diameter.  Kind of neat how that works out.  But when you put skinny 1.25" wide slicks on a mountain bike, your tires are only about 1.25" tall, roughly.  So your new wheel diameter is about 24.5".  And the bike will look different with these skinny tires compared to the big fat knobby tires.

One minor thing to keep in mind is gearing if you use the 26 mountain bike tire size.  Your gearing will be slightly lower compared to 700C tires because the diameter is smaller.  For instance:  A 24 chainring and 32 rear cog on a 700C 35mm tire gives you approximately 20 gear inches (24/32*27).  The same 24x32 on a 26 mtb wheel with a 1.5" wide tire gives you approximately 19 gear inches (24/32*25).  The 27 and 25 are the approximate wheel diameters using 35mm wide or 1.5" wide tires.


Offline sunfisher

26in or 27in bike choice
« Reply #4 on: March 29, 2005, 10:09:15 pm »
Kenda, Continental, Scwalbe all make pretty good touring type tires in
559 size.  I put 4k miles, mostly commuting, on a Kenda Kwest (559,
100psi) before it succumbed to a staple.  I was surprised not to have
any pinch flats given the abuse it took.

I do not think they are slower than 700c in practice, but might be in
theory.