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I don't understand - what is this for?

post #1 of 145
Thread Starter 
See <http://www2.trekbikes.com/Bikes/2007/mountain/69er.html>.

Is the bigger front wheel to better roll over obstacles, or is it just a
demented fashion statement? Conversely, does the smaller rear wheel
provide any real advantage?

What is the deal with single-speed anyway?

Are there prudish Trek dealers out there who will not carry this bike
because the name, or dealers who would be afraid of offending their
customers? Is the "69er" name meant to appeal to the BMX crowd who buys
products such as the "Snafu Rim Job" tires?

Is the Waterloo, Wisconsin water supply contaminated with a parasite
that causes brain dysfunction?

Who exactly is the target market for this bike?

--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful

--
Posted via a free Usenet account from http://www.teranews.com
post #2 of 145

Re: I don't understand - what is this for?

Tim McNamara wrote:
> In article <46b4a85d$0$16326$88260bb3@free.teranews.com>,
> "Tom \"Johnny Sunset\" Sherman" <""sunsetss0003\"@invalida .com">
> wrote:
>
>> See <http://www2.trekbikes.com/Bikes/2007/mountain/69er.html>.
>>
>> Is the bigger front wheel to better roll over obstacles, or is it
>> just a demented fashion statement? Conversely, does the smaller rear
>> wheel provide any real advantage?

>
> Back in the day, Charlie Cunningham built MTBs with a smaller rear
> wheel- IIRC 20" rear and 26" front. Many dirt motorbikes have a smaller
> rear wheel. I have no idea why. Maybe Carl Fogel does, he used to ride
> trials and the like.


I don't know about Cunningham but a few builders, including Cannondale,
built bikes with 24" rear wheels and 26" fronts. In fact, I wouldn't
be surprised if someone still is.

The first purpose-built off-road motorcycles started out with 19" front
and 19" rear tires. Over the years that evolved into 18" rears, and 21"
fronts. Although I haven't kept up with off-road motos so they may be
using different sizes now. I know 17", 18" and 19" rear tires and 21"
and 23" front tires were tried at various times over the last 30 years.

Greg

--
Ticketmaster and Ticketweb suck, but everyone knows that:
http://www.ticketmastersucks.org

Dethink to survive - Mclusky
post #3 of 145

Re: I don't understand - what is this for?

On Aug 4, 10:50 am, "G.T." <getne...@dslextreme.com> wrote:

> I don't know about Cunningham but a few builders, including Cannondale,
> built bikes with 24" rear wheels and 26" fronts. In fact, I wouldn't
> be surprised if someone still is.


My mom used to have a Shogun Prairie Breaker Pro with a 24" front and
26" rear. She felt like she was going to go over the bars when she
descended on it.

She was not in the least bit heartbroken when it was stolen about 12
years ago. She replaced it with a Trek 990 which she rides to this day.
post #4 of 145

Re: I don't understand - what is this for?

On Sat, 04 Aug 2007 12:33:57 -0500, Tim McNamara
<timmcn@bitstream.net> wrote:

>In article <46b4a85d$0$16326$88260bb3@free.teranews.com>,
> "Tom \"Johnny Sunset\" Sherman" <""sunsetss0003\"@invalida .com">
> wrote:
>
>> See <http://www2.trekbikes.com/Bikes/2007/mountain/69er.html>.
>>
>> Is the bigger front wheel to better roll over obstacles, or is it
>> just a demented fashion statement? Conversely, does the smaller rear
>> wheel provide any real advantage?

>
>Back in the day, Charlie Cunningham built MTBs with a smaller rear
>wheel- IIRC 20" rear and 26" front. Many dirt motorbikes have a smaller
>rear wheel. I have no idea why. Maybe Carl Fogel does, he used to ride
>trials and the like.


Dear Tim,

Sorry, but we fooled you.

Don't feel bad, since 9 out of 10 trials riders will mistakenly insist
that their front tires are bigger.

After all, trials machines use 21-inch front rims and 18-inch rear
rims, so the front tire must be 3 inches taller, right?

Nope.

Look at this 2007 GasGas TXT 300cc, which has the standard 21 x 2.75
front tire and 18 x 4.00 rear tire:

http://i16.tinypic.com/4pl4yhk.jpg

You can't tell the front tire from the rear with a yardstick on a
trials machine, particularly if the rider's weight is squashing the
lightly inflated tires.

For practical purposes, the front and rear tires are the same height.
In fact, the height of the tread blocks on a particular model of tire
has more effect on the tire height than whether it's a "21" front or
"18" rear tire.

On the front, the narrow 21-inch rim mounts a skinny 2.75 tire. The
combination is tall enough to roll over obstacles easily, but still
light enough to steer, bounce, and pop up in tricky places. The rim is
strong enough because the leading tire takes less impact, carries less
weight, and has more suspension.

On the rear, the wide 18-inch rim mounts a 4.00 tire, which is so
thick in cross-section that it ends up just as tall and willing to
roll over obstacles as the dainty front tire.

The 4-inch width gives traction for the engine, the huge increase in
cross-section gives more pneumatic suspension at the same 4~6 psi
(think 700x38 versus 700x21), and the massive rim and tire withstand
~400 pounds of rider and machine slamming into waist-high rock ledges.

Since the rear tire steers a gentler curve than the front tire, the
enormous increase in weight doesn't hurt handling.

That's why the original 19-inch front and rear rims were replaced.
They were fine for pavement and okay for fairly smooth off-road
riding, but too heavy and clumsy for the front and not heavy and
strong enough for the rear when riders began bouncing over fallen logs
and big rocks.

Cheers,

Carl Fogel
post #5 of 145

Re: I don't understand - what is this for?

On Aug 4, 1:16 pm, "Tom \"Johnny Sunset\" Sherman"
<""sunsetss0003\"@invalida .com"> wrote:
> See <http://www2.trekbikes.com/Bikes/2007/mountain/69er.html>.
>
> Is the bigger front wheel to better roll over obstacles, or is it just a
> demented fashion statement? Conversely, does the smaller rear wheel
> provide any real advantage?
>
> What is the deal with single-speed anyway?
>
> Are there prudish Trek dealers out there who will not carry this bike
> because the name, or dealers who would be afraid of offending their
> customers? Is the "69er" name meant to appeal to the BMX crowd who buys
> products such as the "Snafu Rim Job" tires?
>
> Is the Waterloo, Wisconsin water supply contaminated with a parasite
> that causes brain dysfunction?
>
> Who exactly is the target market for this bike?
>
> --
> Tom Sherman - Holstein-Friesland Bovinia
> The weather is here, wish you were beautiful
>
> --
> Posted via a free Usenet account fromhttp://www.teranews.com



Hi there.

The smaller rear wheel gives a slightly lower gear than the bike would
have with a 29 rear wheel.

It looks like a trials bike not a mountain bike,

Market? People who like to ride over obstacles.

Cheers from Peter
post #6 of 145
Thread Starter 

Re: I don't understand - what is this for?

Tim McNamara wrote:
> In article <dvk9b3dajck2fd9t3btqsnsefnsjgon03j@4ax.com>,
> carlfogel@comcast.net wrote:
>
>> On Sat, 04 Aug 2007 12:33:57 -0500, Tim McNamara
>> <timmcn@bitstream.net> wrote:
>>
>>> In article <46b4a85d$0$16326$88260bb3@free.teranews.com>,
>>> "Tom \"Johnny Sunset\" Sherman" <""sunsetss0003\"@invalida .com">
>>> wrote:
>>>
>>>> See <http://www2.trekbikes.com/Bikes/2007/mountain/69er.html>.
>>>>
>>>> Is the bigger front wheel to better roll over obstacles, or is it
>>>> just a demented fashion statement? Conversely, does the smaller
>>>> rear wheel provide any real advantage?
>>> Back in the day, Charlie Cunningham built MTBs with a smaller rear
>>> wheel- IIRC 20" rear and 26" front. Many dirt motorbikes have a
>>> smaller rear wheel. I have no idea why. Maybe Carl Fogel does, he
>>> used to ride trials and the like.

>> Dear Tim,
>>
>> Sorry, but we fooled you.
>>
>> Don't feel bad, since 9 out of 10 trials riders will mistakenly
>> insist that their front tires are bigger.
>>
>> After all, trials machines use 21-inch front rims and 18-inch rear
>> rims, so the front tire must be 3 inches taller, right?
>>
>> Nope.

>
> Interesting! Never having and anything to do with motorcycles, I'd not
> thought much about this. The cycling parallel would be something like
> having a 650B X 37 rear and a 700C x 18 front. The overall diameter is
> just about the same, but the section width of the tire is very different.


Or more appropriately if we are talking "French" tire sizing system,
700A (ISO 642-mm) on the front and 700C (ISO 622-mm) on the rear, both
with an approximate major diameter of 700-mm.

--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful

--
Posted via a free Usenet account from http://www.teranews.com
post #7 of 145
Thread Starter 

Re: I don't understand - what is this for?

Sir Ridesalot wrote:
> On Aug 4, 1:16 pm, "Tom \"Johnny Sunset\" Sherman"
> <""sunsetss0003\"@invalida .com"> wrote:
>> See <http://www2.trekbikes.com/Bikes/2007/mountain/69er.html>.
>>
>> Is the bigger front wheel to better roll over obstacles, or is it just a
>> demented fashion statement? Conversely, does the smaller rear wheel
>> provide any real advantage?
>>
>> What is the deal with single-speed anyway?
>>
>> Are there prudish Trek dealers out there who will not carry this bike
>> because the name, or dealers who would be afraid of offending their
>> customers? Is the "69er" name meant to appeal to the BMX crowd who buys
>> products such as the "Snafu Rim Job" tires?
>>
>> Is the Waterloo, Wisconsin water supply contaminated with a parasite
>> that causes brain dysfunction?
>>
>> Who exactly is the target market for this bike?
>>

>
> Hi there.
>
> The smaller rear wheel gives a slightly lower gear than the bike would
> have with a 29 rear wheel.


Why not accomplish the same thing with a smaller chainring or larger
sprocket?

> It looks like a trials bike not a mountain bike,


I thought this was a trials bike:
<http://www.pashley.co.uk/products/26ghz-trials.html> - not much like
the 69er is it? Do US trials differ a lot from UK trials?

> Market? People who like to ride over obstacles.


I usually crash over obstacles [1] in a demonstration of my sub-Barney
riding skills.

[1] No Sorni, this is on my ATB [2], not one of the 'bents!
[2] ATB seems more appropriate than MTB, since there are no real
mountains in most of the Upper Midwest.

--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful

--
Posted via a free Usenet account from http://www.teranews.com
post #8 of 145

Re: I don't understand - what is this for?

In article <46b4a85d$0$16326$88260bb3@free.teranews.com>,
"Tom \"Johnny Sunset\" Sherman" <""sunsetss0003\"@invalida .com"> wrote:

> Is the bigger front wheel to better roll over obstacles, or is it just a
> demented fashion statement? Conversely, does the smaller rear wheel
> provide any real advantage?
>
> What is the deal with single-speed anyway?

....
> Who exactly is the target market for this bike?


personally, i've never gotten the whole single/fixie thing, and
a singlespeed mtb seems beyond useless. i pass at least 5 fixies
a week on the various hills of my weekday ride, never had things
happen the other way around. and i'm a CLYDESDALE, for heaven's
sake. i'm carrying 3 pounds more bike and 20 pounds more of me
up those hills. i had somebody on one of those ultra hip surly
fixies chase me DOWN a hill one time, but he disappeared
at the halfway point when it threw its chain. i have no idea if
he hurt himself but it made an extremely entertaining noise.

sometimes technology marches on for no apparent reason, but the
derailleur was invented to fix a very real problem. so the whole
derailleur/shifter/cassette system adds a couple of pounds to
the total: it gets you where you're going faster and with less
effort.

i'm sure there are a few very specialized areas of competition
where these things are used. i, however, use my bike for
recreation and transportation.
post #9 of 145

Re: I don't understand - what is this for?

On Sat, 04 Aug 2007 16:27:49 -0500, Tim McNamara
<timmcn@bitstream.net> wrote:

>In article <dvk9b3dajck2fd9t3btqsnsefnsjgon03j@4ax.com>,
> carlfogel@comcast.net wrote:
>
>> On Sat, 04 Aug 2007 12:33:57 -0500, Tim McNamara
>> <timmcn@bitstream.net> wrote:
>>
>> >In article <46b4a85d$0$16326$88260bb3@free.teranews.com>,
>> > "Tom \"Johnny Sunset\" Sherman" <""sunsetss0003\"@invalida .com">
>> > wrote:
>> >
>> >> See <http://www2.trekbikes.com/Bikes/2007/mountain/69er.html>.
>> >>
>> >> Is the bigger front wheel to better roll over obstacles, or is it
>> >> just a demented fashion statement? Conversely, does the smaller
>> >> rear wheel provide any real advantage?
>> >
>> >Back in the day, Charlie Cunningham built MTBs with a smaller rear
>> >wheel- IIRC 20" rear and 26" front. Many dirt motorbikes have a
>> >smaller rear wheel. I have no idea why. Maybe Carl Fogel does, he
>> >used to ride trials and the like.

>>
>> Dear Tim,
>>
>> Sorry, but we fooled you.
>>
>> Don't feel bad, since 9 out of 10 trials riders will mistakenly
>> insist that their front tires are bigger.
>>
>> After all, trials machines use 21-inch front rims and 18-inch rear
>> rims, so the front tire must be 3 inches taller, right?
>>
>> Nope.

>
>Interesting! Never having and anything to do with motorcycles, I'd not
>thought much about this. The cycling parallel would be something like
>having a 650B X 37 rear and a 700C x 18 front. The overall diameter is
>just about the same, but the section width of the tire is very different.


Dear Tim,

Exactly--fat or thin, they end up awfully close to the same height.

Incidentally, high-level bicycle trials riding rarely involves tires
"rolling" over obstacles or even pedalling. It's mostly acrobatic
hopping with locked wheels and motionless cranks:

http://www.youtube.com/watch?v=kTAUQrQVTTk&eurl=

In contrast, motorcycle trials still rolls up and over wet rocks:

http://www.youtube.com/watch?v=HwzykvxNeCY

This is closer to bicycle trials:

http://www.youtube.com/watch?v=x5QJCXkYea8&NR=1

Cheers,

Carl Fogel
post #10 of 145

Re: I don't understand - what is this for?

On Sat, 04 Aug 2007 18:36:01 -0500, DougC <dcimper@norcom2000.com>
wrote:

[snip]

>With motorcycles, the reason I was told was precisely because using a
>smaller rear tire allows the tire to be mounted closer under the
>rider+frame, contributing to level-ground traction. On-road motorcycles
>don't bother with it because for them it's not a significant advantage.


Dear Doug,

Sorry, but they told you wrong.

The thick rear 18 x 4.00 tire on a trials motorcycle isn't smaller.
It's just as tall as the skinny 21 x 2.75 front tire:

http://i16.tinypic.com/4pl4yhk.jpg

And level-ground traction is not a problem on a trials machine.

Cheers,

Carl Fogel
post #11 of 145

Re: I don't understand - what is this for?

On Aug 4, 3:33 pm, Fred Clydesdale <f...@belldinger.com> wrote:
> personally, i've never gotten the whole single/fixie thing, and
> a singlespeed mtb seems beyond useless.



We can't all be closed-minded dumbasses.

> i pass at least 5 fixies
> a week on the various hills of my weekday ride, never had things
> happen the other way around. and i'm a CLYDESDALE, for heaven's
> sake. i'm carrying 3 pounds more bike and 20 pounds more of me
> up those hills.



C'mon out and ride with me sometime. I'll show you just how
inefficient singlespeed bikes are. Your weekday ride sounds like it's
loaded with punks and poseurs.

JD 225lbs and can still kick your ass
post #12 of 145

Re: I don't understand - what is this for?

On Aug 4, 3:36 pm, DougC <dcim...@norcom2000.com> wrote:
>
> (-It's a different matter I realize but-) The Cannondale MTB that was
> 26/24 F/R did not use a fatter tire on the back, both were the usual 2.2
> inches. You could tell just by looking, that the front rim and tire was
> visibly taller than the rear.
>
> I remember because I was shopping for a MTB when they were in shops, and
> I remember looking at it and thinking "WTF?". It wouldn't automatically
> turn me off now, but not wanting the hassle of buying 24" tires and
> tubes back then--I disregarded it pretty quickly, without even a test-ride.
>
> I was told at the time that they used a 26 on the front because it was
> more stable-steering than a 24 would be, and they used a 24 on the rear
> because people thought that long chainstays wasted energy somehow, and a
> 24's contact patch could be set closer to the seat tube than a 26.
>


IIRC (becoming more of an issue as time goes by), the 26/24 Cannondale
MTB was called the "Beast of the East", supposedly because the
"eastern" riders demanded a more manuverable bike with a lighter rear
end and higher bottom bracket, as opposed to "western" riders who were
all about bombing down fire roads and could care less about hopping
over roots. Cliques are nothing new.

Jeff
post #13 of 145

Re: I don't understand - what is this for?

once lived upstream from a village had giardia from dem rascally
beevuh. bad news
post #14 of 145

Re: I don't understand - what is this for?

Per carlfogel@comcast.net:
>acrobatic
>hopping with locked wheels and motionless cranks:
>
>http://www.youtube.com/watch?v=kTAUQrQVTTk&eurl=


Every time I watch something like that, I come back to the
commonly-made assertion that the difference between human and
chimpanzee genomes is less than two percent.

Even allowing for a lot of "noise/dead" genes.... I have to
wonder how few genes would need patching to make the diff between
being able to do that stuff and stumbling around like the rest of
us.
--
PeteCresswell
post #15 of 145
Thread Starter 

Re: I don't understand - what is this for?

datakoll aka gene daniels wrote:
>
> once lived upstream from a village had giardia from dem rascally
> beevuh. bad news


Better than some of the diseases one could catch from "beevuh"!

--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful

--
Posted via a free Usenet account from http://www.teranews.com
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