Grant sent along another update which touches on a whole heap of subjects.
It would've been posted yesterday, but I'm several notches under the weather
this week.

-------

New RIV bike geos and fits:
The 48 will fit like a horizontal top tube (htt) of a 51 or to to 56 or so.
The 52, like a 53 to 60; the 56, like a 57 to 63 or so, and the 60, like a
62 to about-how-we-say-a 66. The explanation is simple, and it is: The top
tube slopes UP from the seat lug, NOT down from the head tube. So front-end
height is easily had. If you're on the small end of a new bike size, you'll
probably sink the stem in deep---an odd thing for most Rivvies (I think
that's a Beth Hamon term, not sure), but with the SU (sloping UP) top tubes
(TT), it makes sense. Saddle height is never a problem, not with today's
500mm seat posts.

So...the new sizes will fit a gigantic range of riders, all with four sizes.

I know the SUTT's don't have that Stradivarius look, but the goal of these
new bikes is to make solid, fantastic, versatile, comfortable, lugged steel
bicycles affordable to more people; to make it easier to buy (for instance)
an Atlantis-style bike (touring) even if you can't justify a $3,000 real one
because you aren't a full-time wealthy vagabond. Our bikes have a certain
look, and these will too. But the function and the sense of the SUTT seems
appropriate for the new bikes, and I think it's good to apply a different
Aesthetic Yardstick to a $700 frame than to one that costs twice or more of
that.

The Bleriot has "that Rivendell look," true, but we could never afford to
buy enough of them by ourselves (without QBP's help) to be able to stock
sizes deep enough to ensure good supply, and that matters.

The SUTT is only 6-degrees, or about four more degrees than our current
bikes. It is the same as the BOMBADIL, which you can see on our site. So:
I'm a fan of these bikes even before they're here. Of course, on one hand I
have to be. But on the other  hand, we're the force behind them---they
aren't being forced on us, and now we gotta defend them.  Not at all. I'm
really excited about them.

These days, to me, a nicely detailed bike that forces on you a low bar and
skinny tires. I look at bar height-ability and tire-ability...and lugs,
somewhere along the line.

TRAIL:
I'm GETTING tired of this topic, and have only this to say, for now: You can
get used to anything and learn to love it. The power of suggestion is
strong, especially in Matters of Subtle Differences and Subjectivity. All
that said, Trail is a stabilizing force, which means to some extent is can
make a bike safer to ride, less easily jostled-to-crash than a bike with too
little of it.

I'm not one to quake at the thought of going against the conventional wisdom
when I think it's off, but in this case I don't think it's off. If it were
off, then the tens of millions of happy bikes and riders in the last half
century and before wouldn't have been so happy and content. I understand
that THAT logic can't be applied as successfully to all matters in and out
of bike design, but I think it can apply to trail. There may be certain
circumstances that benefit from a little more or a little less (with the
extremes of riding out there, it would have to be that way), but for
day-in/day-out riding, trail figures in the high fifties to low sixties work
great.

Here's an odd fact that is troubling me some: The current 52 Bombadil, the
one so many people have ridden (including Chico Gino, who reported on it in
his blog), rides great by All Accounts. I have never ridden a bike that rode
an iota better, more pleasantly, easy flowing, easy to control, slippery and
grippy in all the right places. I  have ridden it on several S240s with
weights ranging from 27 to 55 pounds, and no problem, it feels like a bike.
Unloaded, it feels like a road bike (too much like one, for my taste).  The
troubling part is: 68mm of trail. It is troubling because "trailists" will
see that figure (or figure it out from other numbers) and doubt the bike
they'll never even ride. Trail theory says it should suc* going uphills
slow, yet  it doesn't. So right now and over the next week or so I have to
decide between sticking with something that I know works, or "designing to
theory." If I do that, I'll dig  into my bank of experience or whatever it
is and make a conservative shot, but if I do that, I'll feel like I'm caving
in. A slight loss of self-respect, but fewer future headaches?

FLEX:
A certain amount is fine, too much is not, and it's not a significant source
of "energy/speed loss." If you believe that a bike can't be too rigid, then
you'll naturally like rigid bikes better, and equate them with goodness and
speed. If you believe a little flex feels good and doesn't slow you down,
might even help the way a flexy dance floor or gym floor helps the jumps,
then you'll enjoy the slight, nearly but not quite imperceptable flex in a
moderate frame. Too much flex is a problem when it causes "ghost shifting,"
which is real shifting caused by the fame flexing enough to move the rear
hub away from the upper pulley, resulting  in the chain being de-railed to
the next hardest cog. If you're too much guy for a particular frame, you may
find this happening on steep climbs; but check your shift lever tightness
first, and make sure there's no excess friction in the system. Other
opinions abound, and seek 'em out!

Rolling resistance varies tremendously with the surface and tire pressure.
The prevailing opinion, which I go along with, says that rougher roads need
softer tires that roll over and absorb the bumps, rather than hitting them
and bouncing skyward. One example of "conventional tire wisdom" that I
doubt-to-don't-believe, is the idea that a supple sidewall makes a whopping
difference. Sidewall suppleness is most obvious when there's no air in the
tire, and even MORE MOST obvious when the tire isn't even on a rim. Once you
mount and inflate two tires, one with a supple sidewall (SS) and one with a
firmer sidewall (FS), then the differences are insignificant. If both tires
inflate to 75psi feel different, then they will behave differently, too. To
make the FS feel like the SS, you may have to reduce its psi by 5, and there
are no drawbacks to doing that.

But here again, it's kind of a case of magnifying amoebas, since (1)
compared to wind resistsance, rolling resistance is insignificant, and
matters only in races won or lost by wheel-widths; and (2) for anybody who
doesn't race at that supremely high level, it is a mistake (I'd say) to even
give it a second thought. You want a comfortable, reliable bike; a certain
amount of fitness; a friend to ride with, and a safe place to ride. If the
weather's good and the scenery is decent, that's all you need. That's not to
say you shouldn't enjoy discussions about bicycle theoretics, but in the
end, don't forget to re-size their importance...is all.

BUILDER:
New builder is not anybodyanybody knows, I am sure. Builders come with
various degrees of fame and reputation, but no builder imbues a frame
with magical love that flows from his fingertips. It's a romantic
notion, and I'd be the first to acknowledge that the range of skills,
especially in custom builders, varies far more than the prices they
charge. In a custom Riv builder, I am looking for a guy who loves
bicycles and is at home with metal and tools, and has personal metal-
making standards that are higher than my own, and won't take short
cuts. I also look for, and have found somebody with decades (more than
three) of experience building some of his own frames (including a
custom for me way back) and repairing hundreds of the finest frames in
the world. I know it is impossible to stop the speculation, so
speculate away, but  in the end, it will be a RIvendell frame, not a
_______ _________ frame, because it is our design, our lugs, our
concept, our choice of everything. Frames from him are still
months&months away,  and when they finally start to flow, they will
flow glacial-like!

Best, Grant

Thanks for posting this.
Lots of topics that interest me in this one!

On Fri, 16 May 2008, CycloFiend forwarded what Grant P. wrote:

I think he's got that backwards. Lower trail seems to be less bothered by
jostling. I noticed that comparing my Bleriot to my Kogswell. The B was
much more likely to get "off course" (due to wind, accidental bumping
of the bars, inattention, etc) except at very high speeds, where
they seemed equally stable, but with distinctly different feel. I've yet
to crash on either one.
I don't think Riv needs to go the low-trail route, but too high doesn't
feel good to me. I actually don't notice much difference between 30, 40,
and 50mm of trail, but 60+ feels wierd. I don't think "you can get used to
it" is a good answer when considering an expesive bike.

I love flex and will never buy another stiff bike. Unfortunately this may
rule out future Rivendells for me, unless I get a custom. Is this ghost
shifting something unique to modern narrow 9-10
speed clusters? I've ridden some very flexy frames up some very steep
hills, but never had that problem with 6-7-8 speed systems.

I disagree. Once you've found a comfortable postion on the bike, you can't
really do anything about wind resistance without comprimising comfort.
You can improve the tires, though. Faster tires tend to be more comfy
anyway, so it's win-win! I've seen low rolling resistance tires make the
difference between pedalling with a tailwind and being able to just coast along.
I don't really care about speed, but tires that feel faster are simply
more fun than ones that feel sluggish. I really wish Riv would have
Panaracer make a Maxy Fasty with the same construction they use for the
Grand Bois tires. It would be simple to do and make for a fabulous
fast and comfy tire. I'll pre-order four of them!

Thanks for letting me ramble on,

Ryan

Agreed.  Less trail = a less perturbable front end, but also requires
greater steering input to effect a change in direction.  Having said that,
my current favourite bike ever (edging out the RB-1 on the versatility
front) is my '84 Specialized Sequoia, which has medium trail (~55mm) and
handles perfectly well.  All else equal, I prefer lower trail, but it's not
the first thing I look at.  These days, that would be...

I think Dave Mann over on iBOB reported ghost-shifting issues with his
early-80s 531 Treks, but he's the first to point out that this is probably
an effect of Trek using very light (probably .8/.5/.8) tubing on a very
large frame (he rides a 64cm).  I expect the old ultra-flexy bonded-aluminum
Vitus 979s and the like might have experienced similar problems, especially
in larger sizes, but the typical non-OS bike feels perfectly solid,
especially in the regular tubesets and common sizes.  My '92 RB-1 was
probably on the light side for steel production bikes in its size (59cm),
and never a hint of ghost-shifting.

Murray
Victoria, BC

I myself like sloping TT.  Besides having short legs, a sloping TT can
raise your handlebar without a stem up all the way to its limit.
Looks funny IMO.

Another factor which I believe, and others as well is a compact frame
has more "snap" to it.  Keep in mind this is my belief based on my
experience, YMMV for sure.

On May 16, 7:47 am, CycloFiend <cyclofi...@earthlink.net> wrote:

I don't think it is much use to discuss trail without discussing
wheel flop at the same time.  I may not understand correctly, but
if I do, then anything that increases trail will also increase wheel
flop.  And, sure enough, trail DOES stabilize, but wheel flop
de-stabilizes.  When there is little weight on the front fork, the
trail stabilization effect dominates.  When there is lots of
weight on the front wheel, then the wheel flop effect dominates.
At low speeds, going up hill, with a full load on the front wheel,
wheel flop REALLY dominates (personal experience).
Discussing trail without knowing how you are going to use and load
the bike is not very meaningful.

But, I could have misunderstood all this.  If that is so, I would
love to have someone correct me and then maybe I will finally understand
it.

-Doug "anonymous" Shaker

At 10:24 AM 5/16/2008, you wrote:

-Doug Shaker
        Expert Support Inc.             mailto:dsha...@xs.com
        201 San Antonio Circle, #102    voice: 1-650-739-0844
        Mountain View, CA 94040-1234    fax:   1-650-739-0814

That's a good summary, Doug.  I kind of regard wheel flop (the vertical drop
of the axle as the front wheel is turned) as a secondary effect of trail.
It isn't quite that simple, since it is proportional to trail and head
angle, but then trail is itself a partial function of head angle, so...

In simple terms, wheel flop tends to amplify steering inputs, and I believe
it is the major reason why high-trail bikes are easier to put off-course,
either deliberately or accidentally.

My comments on trail were in the context of a moderate rear load (Nelson
saddlebag) with no front load.

Murray
Victoria, BC

On May 16, 1:10 pm, Doug Shaker <d...@theshakers.org> wrote:

and/or TIRES and their PRESSURE.  E.g.:

+ is low trail combined with a skinny, high-pressure tire bad?
+ is high trail combined with a wide, low-pressure tire good?

These are some questions I want to learn the answers to.

See also:

http://sfcyclotouring.blogspot.com/2008/01/apples-to-apples-or-frank-...
http://sfcyclotouring.blogspot.com/2008/05/kogswell-700c-pr-first-imp...

-Jim G

These days, to me, a nicely detailed bike that forces on you a low bar
and
skinny tires. SENTENCE SHOULDN'T END THERE. MEANT TO ADD...
"....looks ridiculous." Sometimes a NICE ridiculous, but still...
Grant

On 5/16/08, gr...@rivbike.com <Grantmill...@gmail.com> wrote:

Hey Grant! Design the Bombadil or whatever else according to your seat of
pants sense of truth, justice and the American Way! Don't let the analyzers
bother you.

I think tho' that there are big differences in how tires feel (tho' I cannot
prove that nice feeling tires *are*faster). I ride skinny, 21 mm Turbos on
559, skinny (19 mm outside) semi aero rims on my '99 Joe and '03 Curt, and
they feel fine, as smooth as the 28 mm (actual) Pasels on my light 531
Motobecane, and this over rough pavement, too. Extreme case: I had an old
Nishik mtb with tire and tube combo that allowed me to ride, literally,
through a briar patch (goadhead carpet), leaving me with literally dozens of
the little bastards to brush off the tires afterward; no air loss *at all*.
Now these tires/ tubes made riding feel as if I were riding against a stiff
headwind up a hill.

Related to tires: My 3 custom Rivs have been far, far stiffer than many
other bikes I've owned -- I could carry 40 lb of groceries on my
erstwhile '95 Waterford custom with nary a sway and in perfect control --
but they *ride smoothly*, more so than many other bikes I've ridden, and
these even with much fatter tires. Long stays? What gives?

Lastly, as to wind resistance: with our strong winds (I often head home into
NWS "25 mph gusts to 35") I personally very much need a low aero position,
even if my average at the end is no more than 15 mph.

Patrick "have a wonderful, permanent, Christian polygamous marriage with my
two custom 26" wheel Riv fixeds" Moore