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Note:
Grant made this
post to the RBW
Owners Bunch list, following a general question about
the geometry of the new frame series. You can find it in the
list archives, but I wanted to keep these points easy to find.
The quickie photo of Betty above is from my too-short test
ride while on an RBWHQ&L visit today - doesn't do it justice
at all, but I'll be posting a comment over on my
blog pretty soon...
Begin
post:
The top tubes "read" long, but the length is sucked up by
shallow seat tube angles and high bars. In fact, they "ride"
normal, maybe even on the short side of normal. Some things
to think about:
¥
MOST riders shove the saddle all the way back on the rails.
Half of those wish they could shove it back more. The limiters
are the seat tube angle, the seat post's setback, and the
saddle rails. It is rare to see a saddle shoved all the way
forward; common for the rider to want it back more. Half a
degree--seems like a good way to go. On my own custom, it's
71-degrees. I'd do that for our non-customs if it wouldn't
raise eyebrows, but...well, here we are!
¥
One degree over 55cm equals one centimeter. So, for a 56cm
frame, it just gives you the possibility (doesn't force it)
of an ant's whisker more than 1cm rearward. The "cost" of
this is that you can't move the saddle as far forward, but
as long you're not poking the saddle toward the bars and wishing
it would go more, the added cm in back is only a benefit.
Does that make sense? It doesn't force you back; it allows
it if you want it, with no drawback UNLESS you're a triathlete.
¥
I have some suspicions as to why shallower STAs are not more
common. One is that riders are accustomed to 72s, 73s, and
74s. Long live diversity of opinion and all that, but I have
to do my best on the bikes I design for our customers, and
I think it's great idea. Minority opinion, whatever--I'm not
saying I'm smarter or others are dumber, just that it makes
sense to me.
¥
Bikes with supershort chainstays won't go shallow, cause the
wheel will hit the seat tube. That's an argument against short
chainstays, not shallow seat tubes.
¥
Most commercially available bottom bracket shells won't easily
accommodate both a big drop and a shallow seat tube angle.
The "rear angle of the chainstay and seat tube sockets is
too steep for it. Our shells are our design, and although
they aren't freaky, they are designed with shallowish seat
tube angles in mind. (This may 'splain why other lugged builders
stick with steep, although it may be a preference, too. They
may believe the myth that short femurs should go with steep
seat tube angles. That is "flat-earth", but it is still the
common belief, simply because it's been repeated and printed
so often. In any case, tiggers can do anything they want,
easily, and they don't seem to take advantage...)
I
am pretty sure RR41 will make things clear. Think of the Da
Vinci drawing of the naked guy with long curly hair extending
his arms. Think of how that applies to arm reach and bar height.
It's key, key, key...
Anyway,
it's only half a degree--and probably should be a whole one.
All it does is expand your rearward options by removing a
centimeter of your forward options (less on a 48 or 52; a
bit more on a 60). It's not a bad deal.
Bill
M. is entirely correct----the halfa degree just gives you
that much more real estate in the area you want it.
We
have the 56 in now. By Jan 2 - 4 we'll have another 56, plus
two each of the 48s, 52s, and 60's. They're coming in painted
colors that won't be final, so we'll repaint some of them,
and that'll take a week--but by Jan 12 we should have all
sizes available for testing-- and if any of you are local,
I sure hope you come by and try them.
We'll
set them up with average stems, normal bars, and you're free
to take them for an hour, and...it'll be fun!
Grant
direct
link to original post
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The
announcement that the Bleriot was going away provoked a number
of responses, and Grant emailed me a couple of updates regarding
the newer models - both of these appear in the RBW
List at Google groups, and I'd encourage you to follow
through all of the discussion which followed. But, I have
found myself quoting the original posts so many times, I thought
it would make sense to put them somewhere easy to find:
GP
Notes on the Bleriot, new & current models and a Quickbeam
run
Bleriot etc:
I got tired of too many dealers de-dignifying it as a loss
leader, and so I'm just pulling the plug on the whole Bleriot
program. That means that after about late June, no dealer
who doesn't have them will be able to get them. We'll then
be obligated to buy up QBP's stock, which will give us enough
'riots for a few months, maybe even through winter. They will
not go on sale; still $750.
The
QBP partnership was pleasant, I have only the best things
to say about QBP, but it was about a dozen and a half dealers
that sealed the Bleriot's fate.
We
could, I suppose, continue to get them ourselves. But the
original deal was created with the help of QBP's trading company,
and it wouldn't be fair for us to tie up its time with business
that no longer involves QBP. So rather than put them in the
position of "handing off" the Bleriot deal to a competitor
trading company--after they'd worked so hard on the details--I'm
just going to kill the fine bike and start fresh with another
trading company and a few more bikes, which--if all goes well
which it hardly ever does--will be ready in about January,
March, May, and July of 2009.
The
concepts are: Cheap Quickbeam, cheap A. Homer/Saluki, cheap
Atlantis, and cheap Mixte. The plan is four sizes each: 48-52-56-60,
all with 6-deg upsloping top tubes (like Bombadil), so each
size will fit a wider rage of leglengths/riders.
I
say "cheap," but the quality will be the same as the Bleriot.
Made in Taiwan. Our lugs, crowns, bb shells, tube pick, 'ame
& 'phics, all that. Probably they'll be one-color (no cream
head tube), and m-m-may retail for $700 or a hair less (not
$699.99!).
Our minimums per bike are 150. So, four sizes is about 37
each, which will give us good depth and stock for a while.
Meanwhile,
we are getting in a last run of real Quickbeams---70 of them
late this summer, in Silver with blue graphics.
Toyo's
production is low and slow on the normal bikes, so we're supplementing
it with Wford A. Homers and then some Atlantis frames. Toyo
sort of expects to catch up in about 9 months, but I'm not
optimistic, and that's why we're relying on Wford to fix the
slack.
Customs:
Curt's on his own now, and we're training a new builder (new
to us). I know this guy, have for 25 years, he's done repairs
for us for 3 years, he does NOT have his own brand and says
he wants nothing to do with it, and I actually believe him.
First he'll build 30 protovelos for us--or however many it
takes for him to get his groove and get really comfortable
with the particulars of our bikes.
I'm
tired of frustrations, but overall things are really good.
We have a new (second) full-time shipper; Miesha's back and
here with her baby (Freddy) and doing well. The site is getting
better. We'll soon have instructional youtube videos for various
things we get asked about all the time (twine, shellac, mounting
racks, and then just fundamentals like fixing flats).
GP
on upcoming rivbike fits, sloping top tubes, trail, flex,
rolling resistance
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
Links
to original posts on the RBW
list:
GP Notes on the Bleriot, new & current models and a Quickbeam
run
GP on upcoming rivbike fits, sloping top tubes, trail, flex,
rolling resistance
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