Conference noted::bicycle

I haven't paid too much attention to this area recently - last I recall, 
though, sewups still had a rolling resistance/weight advantage over any 
type of clincher. (If anyone has info to suggest this is no longer true, 
please post it). If you only want to use 'em for TTs, I'd get a light 
set of sewups and equip 'em with a nice set of silks...... use clinchers 
for training.

A reduced # of holes should be no problem for someone as light as you 
are. I used to occasionally see ads for spokes that had elongated cross 
sections (ie narrow edge into the wind). No idea where you would find 
'em nowadays.

There may be some things to do to the bike to increase TT performance -
a favorite of mine is to crank the rear dropout adjusters all the way 
forward, shortening the wheelbase and making the bike stiffer. 

Let us know what you decide and how it works out....
                                                          ken

    I recently built up a set of "fast" wheels and this is what
    I came up with.  For hubs I used 32 hole new campy aero
    hubs (I got a whole groupo from Nashbar for $450), Araya
    model 1 tubular rims, Alpina quasi flattened 18/10 spokes, 
    and my ever
    favorite Victoria CX/CG tires.  From riding these wheels
    for about a month, they seem very strong and fast.  I like
    to stay with campy hubs because no spacing has to be changed
    when switching wheels.  I've had super luck with Victoria
    CX/CG tires, the last pair I got at least 4,000 miles without
    a blowout.  If you go the tubular route, look for someone
    else locally who needs the same tire and make a bulk order.
    I personally think that tubulars provide a better ride than
    these new high pressure clinchers and would be faster to
    change in a Triathlon race and easier to carry a spare.
    
    True aero spokes are made by DT but the hubs must be filed
    out to accomodate the width of the spoke.  This is a very
    tedious process.  Has anyone done this and would like to
    comment?  I have heard rumors that 32 spoke wheels are
    actually stronger than 36 hole because spokes opposite
    one another are in a perfect plane.  Has anyone else heard
    this?
    
    Ambrosio makes a Aero clincher rim that I believe is
    lighter than the Sun, its worth investigating.
                                
    happy wheel building
    

	From recent reading:  In a time trial or distance event the
	gain in speed attributable to aerodynamics is MUCH greater
	than any gain you get from saving weight in the rims.  This
	means: go for aerodynamic rims, flat spokes, fewer spokes
	and radial spoking (zero cross).  You can (and should) fairly
	much ignore the weight of the rims.

			-John A. Wasser
			(I'm not an expert, I just follow the literature)

Thanks for your opinions, I will keep everything that you said in mind
when I decide what to do.

RE: 1   Specialized has run a number of adds in bicycle/triathlon magazines
        where they compare the rolling resistance of their turbo s and r tires
        against other clincher and sewup tires. Of course they give the best
        performance in their tests results. The only thing is, Clement or 
        Vittoria or some other tire maker may have their own test results 
        which show their tires are the best. Who really knows ? One other
        interesting thing. Most of the increased performance in rolling
        resistance comes from high pressure of 115 psi and not from the bald 
        tire.

RE: 2   My favorite bike shop said the same thing about filing the flat spokes
        and would rather not do it. I found the Alpina Spokes in a Nashbar 
        catalog. They sound promising. Can I assume that the Alpina spokes have
        no surprises and do not need filing ?

RE: 3   John, what was your source of info? I would like to read the article
        if I can find it.

Any other opinions on time trial wheels ?

                  Forever trying to gain an extra 2 seconds,

                                      Keith

    
    Some good stuff in this note.
    
    First, let me steer you away from clinchers and into some real tires...
    18mm sewups. They're what the pros are using. Very narrow, extremely
    low rolling resistance. But don't forget that any tire with low
    RR gets that way because the contact patch is smaller, and therefore
    you have less "grip". So be careful with any tire like this, they
    don't handle as well as a wider tire. I tried riding my 18mm wheels
    at the Tour de Lowell one year, I've never been so scared on the
    bike. If you're really serious about triathlons, then you won't
    go with clinchers. Have you ever tried to mount one of those Kevlar
    beaded tires? Try it when your hot, sweaty, and overly excited.
    You casn change a sewup and be back on the road in less than 3 minutes
    if you practice.
    
    The BEST 18mm sewup rims are Assos, but they're big bucks, like
    $140/pr. They weigh 290 grams and are deceptively strong. If you
    can afford them, do so. I couldn't, so I went with Mavic CX18's
    at around $70/pr. 310 grams, super strong, and they're Mavic. I
    went the conservative route, using 32 holes, and I now regret it.
    The Araya aero rims are light but soft, and everyone I know that
    races on them doesn't have them very long. I don't know anything
    you don't already know about the Matrix Iso.

    As far as spokes go, some bladed spokes require hub filing and others
    don't. If I remember correctly the Aeralpina's don't. Beware that
    these spokes aren't as strong or as durable as, say, a 15/16/15
    DT. 
    
    Wolber, National (Panasonic) and Dordoigne (I use these) make the
    tires. More manufacturers probably do now. They're a bit more expensive
    than a standard cotton tire but not as much as a Seta Extra. You
    can really pump up those Dordoigne's, I use them at 160 lbs for
    TT.
    
    Roval makes a pre built wheelset, using their hubs, rims and spokes.
    12 spokes in front and 18 in the back.
    
    Recommendations:
    
    Assos or Mavic CX18 rims - 28 hole
    
    DT 15/16/15 stainless round spokes
    
    National 18mm tires - 150 gram
    
    Campy Nuovo Record hubs - there's no Super Record hub made today
    
    
    GO FOR IT!
    
    CdH
    
    

	Some further reading (My sources can generally be attributed
	Bicycling magazine somewhere over the last six months):

		Drag reduction (in grams of drag at 30mph for front
		wheel only):

		18mm tire vs. 1" tire = 	30 to 60
		Aerodynamic rim vs Flat rim =	30
		1 less round spoke =		 4
		1 flat spoke vs round spoke =	 0.6

	With a 18mm aero rim front wheel with 24 flat spokes (radial)
	you can gain 16.9 seconds in 10 miles (1 minute 56 seconds in 
	100 kilometers)	over a 1" flat rim front wheel with 36 round
	spokes.

	With a disk wheel you would gain 25.4 seconds in 10 miles and
	2 minutes 59 seconds in 100 kilometers.

	Moral:  Get the narrowest aerodynamic rims and tires you can find.
		Switch from round to flat spokes.
		Remove as many spokes as you can.
		(28 or fewer spokes are needed for road racing)
		(24 or fewer spokes are needed for road time trials)
		(fewer than 24 needed for track)
		(12 spokes produces an almost unusably floppy wheel)
	
	Prices (from Mike's Cyclery):

		Assos 16mm aero rims, Campy NR hubs, DT flat spokes
			(front) 24 spokes radial
			(rear)	28 spokes radial on left, 2 cross on right
			$310.00/pr.

		Ambrosia Enervit Linticular Pro
			Lens shaped disk wheel	(limited production)
			$1410.00 each

		Ambrosia Enervit Pro
			Flat disk wheel	(production model)
			$429.00 each

    
    >fewer than 28 needed for road time trial
    >fewer than 24 needed for track
    
    Not necessarily true. A 24F/28R is very unusual on the racing circuit,
    almost all riders use 28F/28R or 28F/32R because a lot of these
    TT's involve hills and rough roads, both excessive stresses for
    sparsely spoked wheels.
    
    As for the track, some kilo and pursuit riders use less than 24
    spokes, but they're light, and have perfected their technique to
    keep the wheels intact. Most sprinters use at least 32 spokes and
    the real heavy ones (Vails,Gorski) use 36.
    
    I wouldn't make these blanket statements for our everyday rider.
    
    CdH_an_everyday_racer_but_not_this_year
    
    

    
    	Please may I extend/change the subject ?   No ?   Well, I'm
    going to anyway:-
    
    	Lotsa good stuff here, but most of the respondents are making
    some fairly reasonable assumptions about the rider's intended course
    and capacity.  Can we please hear more from him on this ?  We havn't
    talked much about other changes to the bike either, which is where I
    want to extend/change the subject. 

    	Most of what follows will probably already be known to the
    originator, but may be of interest to other readers of this note,
    it'll probably bore Chris DeHahn to tears.
    
    	From .0 I assume that this is for a fairly regular bike that
    will be ridden at other times, i.e. the special wheels go on for
    TTs, the rest of the week its a GP bike.

    	The greatest rim selection (widths, # holes, weight, etc.) are
    available for tubular tires, particularly at the end of the scale
    you asked about.
    
    	If it is a reasonably flat course then consider fairly high
    gearing, you may be able to go to a five or six speed by moving the
    outer chainrng to the inner position and abandoning the inner
    chainring.  It is worth making up a special cluster, you may be able to
    got to only three or four sprockets once you know the course and
    yourself very well.  Try for straightest chainline on the gear that you
    will use for the gentle up grades.  Run your chain very slack, its
    surprising how much drag a "properly tensioned" derailleur puts on the
    drive train.  It should look like its going to jump off, but if
    it and the rest of the drive train are in good condition it won't.
    
    	Reg
    
    	(More later, gotta run !)
    
    

I consider myself a more sophisticated cyclist than the average bicycle rider.
However, I must admit that I am impressed with the knowledge expressed by 
those who have replied to this note. If anybody who reads this file is new to
cycling or wants to learn more, then this bicycle notes file is one excellent 
resource. Much of the info given is better than can be obtained in many bike
shops. Well, I guess I should get back to the main topic.

RE .8  As the originator of this note I would welcome other advice about time
       trial bikes in addition to wheels. First of all, I guess I should give 
       some more info on my bike as you asked. It is an Italian made Viner
       Stellar Pro with steep angles (74 and 75 degrees I think) made of
       Columbus SL tubing throughout. Superbe Pro derailleurs and pedals, 
       Ofmega Mistral crankset, Sedisport chain, ultra 7 freewheel. It comes
       in at about 20 lbs even. I have 2 bikes, one is for bad weather, wind
       trainers and touring. The Viner is for training and racing. I will
       probably do about 7 races this summer and they will be on all types of
       courses. I am a strong climber probably because of my light weight but
       I seem to lose ground to my competitors on my descents. We have some 
       very big hills here in Colorado so I will probably want to use an 
       ultra 7 freewheel with a range of 13-24. I'm kind of lazy plus I don't 
       have very many good tools so I'll probably pass on changing freewheels 
       or going down to 1 chainring. However, I think your ideas are excellent 
       and I may try it some time if the race is important enough. I will not 
       be concerned with changing flats in most races because if I flat, I will
       not be able to reach my goals. If the race is long, like a half 
       Ironman then maybe I could still reach my goals if I flat but I'll
       only do 1 or 2 of those a year. Most of the time I will leave the pump, 
       spare tire etc. in the car. 

Two other questions. It seems to me that I once read an article by John Howard
on time trials where he said that it is better to pound away with a higher 
gear at a slower cadence than one would in a USCF race. Is this true? Is it 
also true when climbing ? 
What about pedals? Are the new pedals without clips and straps better for 
aerodynamics and time trials?

                          In search of the ultimate bike,

                                         Keith

    
    Re: Reg
    
    	I'm never bored by anything you say.
    
    The Viner Stella is an excellent bike which was designed expressly
    for light weight. They don't use the heavier Cinelli cast frame
    components (BB shell, lugs) but lighter pressed ones. It is a very
    good bike for road racing, although the geometry is a bit of overkill
    for TT or triathlon, where a slightly longer and more relaxed position
    is desireable. For your needs, though, it's great.
    
    If you are having trouble on the descents, it's because you:
    
  	o  are undergeared
    
    	o  lack proper technique
    
    	o  don't want to die
    
    All of which are valid reasons! In Colorado, you can afford to carry
    a 12 tooth gear. You've got the right derailleurs for the Ultra-7,
    so why not pick one up? Out here in New England I usually carry
    a 12-19, 12-22, or 12-24 depending on the terrain of the road course
    (crits and TT's always 12-17 or 13-18). You won't use the 12 often
    but when your in it you'll be glad you had it. At last years Greenfield
    RR the finish was a slightly downhill field sprint and I didn't
    have a 12, there was no "sprint" per se, it was just a windup of
    your biggest gear. I just slipped back through the pack spinning
    my 53-13 wildly.
     
    Proper technique for descents is also important. Get your chin down
    as far as you can. Slide forward in the saddle a bit to get more
    weight over the front wheel. The G-forces you'll be fighting trying
    to negotiate that turn at 50+ mph are staggering, you'll need all
    your strength focused properly. Try to get as flat as you can on
    the bike. Some guys use a tuck position with their hands on the
    top of the bars and their elbows folded. That scares the heck out
    of me, I like the feeling of more control so I'm always on the drops
    with my elbows slightly bent.
    
    And don't forget to be afraid. Overconfidence will kill you. A liitle
    respect for your life doesn't hurt. Breakaways almost NEVER get
    away downhill, they'll get caught real quick, so don't panic if
    they're getting away.
    
    As for Howard's theory, it corralates with his riding style. He
    tends to push big gears most of the time. Personally, I'm a spinner
    but in the TT I try and push the biggest gear I can at 85-90 rpm.
    I find myself TTing against guys much bigger and stronger than myself.
    So I try and use all my strength by pushing against the highest
    resistance. I don't advocate this for everyone, I'm just saying
    that altering my technique for this event works for me.
    
    Best of luck in all your racing,
    
    CdH
    
    
    

    The latest edition of the Performance Bike Shop Catalog lists a
    true bladed spoke (as opposed to oval, where the aerodynamic benefit
    is reduced) which do not require filing of the spoke holes in the
    hub.  This advantage is derived from the spokes having an "S" shaped
    spoke head which is threaded into the spoke hole.  This eliminates
    the requirement of passing the entire spoke thru the hole.  The
    spokes come in boxes of 75, with alloy nipples, for $34.95.  Address
    fo PBS for those who are interested is:
    
    	Performance Bicycle Shop
    	P.O. Box 2741
    	Chapel Hill, N.C. 27514
    
    phone orders:
    
    	800-334-5471
    
    Before I sign off I should also mention that I have had no experience
    with bladed spokes, nor have I ever used or seen this "S" shaped
    spoke head before, so this is by no means an endorsement.  I would
    like to hear from anyone who does know about how these spokes are
    in use.
    
    Jim

I just wanted to say thanks to everybody who has contributed to this note.
I feel that I have learned quite a bit by reading your responses.

Here's the setup that I finally got :
  
  Campy N.R. 28 hole hubs.
  Alpina aero spokes. 
  Sun Metal Mistral Aero 28 hole clincher rims.
  Turbo R 115 psi tires.
  Ultra light tubes.
  12-24 ultra 7 freewheel.
  Assembly was 3 cross in the back, 2 cross in the front.

Every now and then I do a time trial at the Air Force Academy with some 
friends. I tried the new wheels and did the 12.5 mile circular course about 
50 seconds faster than my previous best time. But who knows, maybe the wind 
was at my back at critical points or maybe I was just in better shape. But 
I do think that they made a difference at higher speeds especially during 
the 4 mile descent on the Academy course.

I would have gone with the Performance spokes if I had know about them 
earlier. I am also going to look into changing my outer chainring from a 
52 to a 53.

                            Thanks again,

                                   Keith

    
    Going from the 52 to the 53 will take a few weeks to get used to
    but is well worth it in the end. You can really notice the extra
    top end in all your big gears. We've got a real moose on the team
    that uses a 55, and, yes, I've seen him in the 12.
    
    Good luck racing,
    
    CdH