This article is from the Bicycles FAQ, by Mike Iglesias with numerous contributions by others.
From: F.J. Brown <F.Brown@massey.ac.nz>
D.H.Davis@gdt.bath.ac.uk gave some useful hints on mounting clinchers,
mostly involving the use of copious quantities of baby powder, and
trying to convince me that clinchers aren't difficult to mount, so ease of
mounting isn't a valid reason for preferring tubulars.
wernerj@lafcol.lafayette.edu wrote that although average tubulars ride
'nicer' than average clinchers, there are some clinchers around that ride
just as 'nice'. He also said that ease of change isn't a good reason for
preferring tubulars as if you flat in a race, you're either going to swap
a wheel or drop out. He pointed out that tubulars end up costing $20 -
$80 per flat.
ershc@cunyvm.cuny.edu gave some of the historic reasons that tubulars were
preferred: higher pressures, lower weight, stronger, lighter rims. Said
that only a few of these still hold true (rim strength/weight, total weight),
but he still prefers the 'feel' of tubulars.
leka@uhifa.ifa.hawaii.edu started this thread with his observations on
clinchers seperated from their rims in the aftermath of a race crash.
stek@alcvax.pfc.mit.edu comments on improperly-glued tubulars posing a threat
to other racers by rolling off, and noted that this couldn't happen with
clinchers.
jobst.brandt@stanfordalumni.org agreed with stek, with the additional note that
it is inadequate inflation that often allows tubulars to roll.
Kevin at Buffalo agreed with stek and jobst about tubulars (improperly or
freshly glued) sometimes rolling.
ruhtra@turing.toronto.edu says he uses clinchers for cost and convenience.
Clinchers let him carry around a tiny patch kit and some tyre irons, costing
60c, whereas tubulars would require him to carry a whole tyre, and would
cost more.
CONCLUSIONS: THE CLINCHER VS. TUBULAR WAR
Tubulars - used to be capable of taking higher pressures, had lower weight
and mounted onto stronger, lighter rims than clinchers. Clinchers
have now largely caught up, but many cyclists thinking hasn't.
Tubular tyre + rim combination still lighter and stronger.
- are easier to change than clinchers. This matters more to some
people than others - triathletes, mechanical morons and those
riding in unsupported races.
- cost megabucks if you replace them every time you puncture.
***However*** (and none of the North Americans mentioned this)
down here in Kiwiland, we ***always*** repair our punctured
tubulars (unless the casing is cut to ribbons). The process
doesn't take much imagination, you just unstitch the case, repair
the tube in the normal manner using the thinnest patches you can
buy, stitch it back up again and (the secret to success) put a
drop of Superglue over the hole in the tread.
- can roll off if improperly glued or inflated. In this case, you
probably deserve what you get. Unfortunately, the riders behind
you don't.
Clinchers - can be difficult to change (for mechanical morons) and are always
slower to change than tubulars. Most people still carry a spare
tube and do their repairs when they get home.
- are cheaper to run: if you puncture a lot clinchers will probably
still save you money over tubulars, even if you repair your
tubulars whenever possible. Tubulars are only repairable most
of the time, you virtually never write off a clincher casing due
to a puncture.
- have improved immensely in recent years; top models now inflate
to high pressures, and are lighter and stronger than they used
to be. Likewise clincher rims. Some debate over whether
tubulars are still lighter and tubular rims stronger. Probably
depends on quality you select. No doubt that high quality
clinchers/rims stronger, lighter and mor dependable than cheap
tubular/rim combination.
 
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