fixie frames

Rick Onanian <[email hidden]> wrote in message news:<[email hidden]>...

Quoted message said:

Kinky Cowboy said:

Has anybody built an "inverted phantom" by using a pair of derailleur pulleys running on the
outside of the timing chain run, linked by a free floating pair of tie bars? This would give more
chain wrap on the timing rings (negligible advantage) and the timing chain would be running
through a closed loop so it couldn't eject the tensioner over rough ground, which looks possible
with phantom rings. A selection of mounting holes for the pulley axle bolts would give all the
adjustability you could need.

Funny you should ask, I was just about to post this:
gallery.consumerreview.comslacker.jpgOpen ↗

I found it when I googled for phantom chainrings to try to learn more.

Dear Rick,

Unfortunately, the jpg of the Phantom squeezer chain-tensioner bears the name of ethirteen and urges
the viewer to visit:

www.ethirteen.com

The unluckily named site appears to be a Phantom, so the device may be hard to find.

If the unavailable Kit doesn't work, you might end up as a Walker.

The Ghost Who Walks

In <[email hidden]>,
[email hidden] (Carl Fogel) opined:

Quoted message said:

www.ethirteen.com

The unluckily named site appears to be a Phantom, so the device may be hard to find.

Nah, they just don't know their own addy:

e13components.come13components.comOpen ↗

But:

e13components.com000014.htmlOpen ↗

Aww, I guess actual production is more work than they want to do...

--
[email hidden] | depending, of course, | REPLACE example WITH Dave Salovesh | on your
perspective | mindspring TO EMAIL ME (After more than a decade on USENET , it's finally come
to this ^^^)

Zog The Undeniable said:

Top Sirloin said:

On Sat, 27 Dec 2003 23:35:45 -0600, A Muzi <[email hidden]> wrote:

(Seatpost diameter is a quick rough guide to

Quoted message said:

frame material)

Could you elucidate please?

25.4mm seatpost = gas pipe (I have one).

27.2mm seatpost = 531 or other decent steel [1].

On the basis that all road tubes have standardised OD because they have to fit standard lugs.

[1] if 531 is silver brazed with a gentle heat so that the seta tube does not go out-of-round it
will take a 27.4mm post without any reaming. Few builders do this.

Coolness. Thanks!

--
Scott Johnson "Always with the excuses for small legs. People like you are why they only open the
top half of caskets." -Tommy Bowen

Tom Sherman said:

Kinky Cowboy said:

... An eccentric BB changes the relationship between the three contact points, and the effective
chainstay length/wheelbase, every time you adjust the chain

How would an eccentric BB change the effective wheelbase, as the rear wheel is located in the
same place?

Tom Sherman – Close to 41½ N, 90½ W

Oops, a cut and paste too far! But I forgot to mention that it does change the BB height,

Kinky Cowboy*

*Batteries not included May contain traces of nuts Your milage may vary

Quoted message said:

On Sat, 27 Dec 2003 23:35:45 -0600, A Muzi <[email hidden]> wrote: (Seatpost diameter is a
quick rough guide to

Quoted message said:

frame material)

Top Sirloin said:

Could you elucidate please?

Sure. Premium 1-1/8" tube is thin. Uses a 27.2 post.

Cheap 1-1/8" tube is thick and even sometimes seamed. Uses a
25.4mm post.

Mid price 1-1/8" tube is inbetween with 26.2, 26.4 seatposts for heavier frames than 26.6 or 26.8
seatpost tube sets.

Only a rough guide but useful to 70s-80s-90s Japanese used frames if you have an allen key to peek
at the stamping on the seatpost.

--
Andrew Muzi www.yellowjersey.org Open every day since 1 April, 1971

Tom Sherman said:

A Muzi wrote: ....

Quoted message said:

Moving the axle is the best way to tension a chain, IMHO, but that doesn't stop guys from seeking
complexity.

Maybe I am missing something here, but doesn't moving the axle back and forth in a set of
horizontal fork ends lead to the possibility of having the rear wheel out of alignment with the
frame (i.e. the two are not parallel)? This would not occur with the use of either an eccentric BB
or the ENO hub (assuming the frame is straight).

Tom Sherman – Close to 41½ N, 90½ W

Uh, not really. In fact, one usually works the wheel incrementally from each side in turn to end
with proper tension and a centered wheel. Sounds harder than it is, ask any fixed/single rider

--
Andrew Muzi www.yellowjersey.org Open every day since 1 April, 1971

On Tue, 30 Dec 2003 20:28:25 -0600, A Muzi <[email hidden]>

Quoted message said:

Quoted message said:

On Sat, 27 Dec 2003 23:35:45 -0600, A Muzi <[email hidden]> wrote: (Seatpost diameter is a
quick rough guide to

Quoted message said:

frame material)

Top Sirloin said:

Could you elucidate please?

Sure. Premium 1-1/8" tube is thin. Uses a 27.2 post.

Cheap 1-1/8" tube is thick and even sometimes seamed. Uses a
25.4mm post.

Mid price 1-1/8" tube is inbetween with 26.2, 26.4 seatposts for heavier frames than 26.6 or 26.8
seatpost tube sets.

Only a rough guide but useful to 70s-80s-90s Japanese used frames if you have an allen key to peek
at the stamping on the seatpost.

I always thought the 27.2mm seatpost in 531 tubes was due to the single butted seat tube, hence
27.0mm in the much lighter 753 set because the seat tube had a butt at the seat lug as well as
at the BB.

The general pricipal of your post is true, but there are quite a few tubesets (especially Japanese
tubes) which share a 26.8mm seat post (tube wall thickness 0.9mm at the lug) but with wall thickness
in the middle of the tube could range all the way from 0.5mm to 0.9mm plain gauge

Kinky Cowboy*

*Batteries not included May contain traces of nuts Your milage may vary

Sheldon Brown said:

Ryan Cousineau said:

It may not be true on this bike, but it appears that if you could adapt this tensioner design so
that the tensioner still had chainstay clearance when the bottom chain-run came tight, you could
make a tensioner work on a fixed-gear as well.

If it was a spring-loaded tensioner, it would still cause the top run of chain to go slack, and
likely derail.

Not if there was another one above the hub, which would ordinarily be level, but would act as a
tensioner when applying reverse torque.

[Yes, this would be an utterly perverse arrangement, not least because of the slap when going from
forward to reverse torque or vice versa... but it would work. The tensioners could be pretty
short, too.]
--
David Damerell <[email hidden]> flcl?

Quoted message said:

I'd like to build a fixed gear bike, but only currently have an old MTB frame available. Is this
ok to use, or should I wait until I can find a road frame to invest in?

Thanks to everyone for the great technical feedback on building a fixie. It's clear that with a bit
of determination and the help of Sheldon and Harris Cyclery, I could build a fixie from an old
wheelchair and a pair of 747 wheels. The MTB frame I have has removable dropouts which I could copy
in horizontal form, so there's no problem doing the conversion with off the shelf parts. There's so
much clearance, I could probably even run 27" rims. But actually, my original, poorly phrased
question was more about the ride-ability of an MTB based fixie.

I've been sold on the training benefits and joys of riding a fixed gear, but wanted peoples input on
whether these benefits are compromised by using an MTB frame as opposed to road, i.e., MTB geometry
vs road geometry. I should clarify that I am a recent convert from off-road to road riding. Though I
still ride off-road, I'm now spending most of my time on a recently acquired ti/ultegra road bike,
and love the new physical and mental challenges posed by it, as well as the incredible sense of
power, efficiency, and speed!

So, to restate and clarify my original question: if I want to build a fixie to enhance my road
skills and fitness (as well as to maximise the "joys" of fixed gear riding), should I start with
road frame geometry, or would an MTB based fixie be just as good?

thanks in advance, byron

Byron Sheppard said:

So, to restate and clarify my original question: if I want to build a fixie to enhance my road
skills and fitness (as well as to maximise the "joys" of fixed gear riding), should I start with
road frame geometry, or would an MTB based fixie be just as good?

Just to add variety, my own favourite fixie began life as a Kona Kilauea. The previous owner had
track ends fitted when one of the dropouts cracked.

makeashorterlink.commakeashorterlink.comOpen ↗

(The bandwidth may max out if the link gets too many hits).

The weight penalty over a road-bike-based fixie isn't significant. It does everything a road fixie
needs to do, plus it has clearance for 2" tyres and reverts to a single-speed mountain bike when I
want it to. If I had to have a single fixie, this would be it.

James Thomson