Soon to try latex tubes. (Done Deed)

Anecdotal findings
Dear Lennard,
I realize from your recent article that several teams are using tubeless tires at this year's Tour. That seems like the way of the future, but as for the ways of the past: How many teams are still using tubulars? And of those teams using clinchers, do they use latex tubes, butyl tubes or something else? It's a hassle to pump them up every day, but for me nothing beats the ride of latex tubes.
Chris
http://www.velonews.com/tour2005/tech/articles/8566.0.html
 
Expert findings

Jobst Branst, opining on whether it's good practice to powder or lube a tube
http://www.sheldonbrown.com/brandt/talcum.html

Jobst Branst, on rolling resistance
http://www.sheldonbrown.com/brandt/rolling-resistance.html

Sheldon Brown, on tubes
Butyl vs Latex
Before World War 2, tires and tubes were made from natural latex rubber, harvested from tropical trees. When the supply of natural latex was insecure during the war, a substitute, "butyl" was invented. Butyl turned out to be a very successful substitute, better, in fact, than latex for this application. All modern tires and most inner tubes use butyl rubber.

Some riders prefer latex inner tubes, because they can be a bit lighter than butyl ones. Some riders believe that latex tubes have less rolling resistance than butyl.

Latex tubes are commonly a bit more porous than butyl ones, and need to have their pressure topped off more often.
http://www.sheldonbrown.com/tires.html#tubes
 
Hi,

Lately, since doing some tweaks to my blue cruiser
(formerly nicknamed "Pig2Pedal"),
it has become more fun to pedal.

Being a noob, I had to learn that everything counts:
the slightest drag of a single brake pad costs efficiency.

The new Drain Brain's meterings highlight how sensitive a bicycle's
sensitivity to load changes. For instance, if I should be crusing on electric
at say, 15mph, and at 250W power draw,
a miniscule drag of the brake will easily up the power draw by 100W.

The idea/notion that latex tubes, being thinner and much more alive than butyl rubber, appeals. So, having realized that even a fat tired bike can be relatively "light" feeling to ride under good conditions,
well, if the latex tube offers a modest extra-free glide, good!

The rear wheel of my bike carries the most weight, and therefore has the greater rolling resistance.

When I get the pair of Michelin Aircomp tubes I'll mount one in the rear tire and see from that if I can feel a difference.

I sort of doubt whether I can "prove" it's easier to run, either by Drain Brain or by feel alone---but who knows?
The placebo effect can be very persuading--toward true, uh, false impressions.

The Bontrager Big Hanks are thinwall tires without tread.
They are very supple; completely the opposite of the blue bike's stock Kenda Flame tires.
They made a great improvement in pedal-ability.
They are, moreover, the lowest rolling resistance slicks of their width on the market. I do not even find other brands in 2.5" width;
2.3" being the more usual for the largest standard balloon tires.

The other expectation is a gain in puncture resistance.
I've not had a puncture yet; our roads are not particularly littered with glass, and there are no thorns here.

---well, it may be fun. :) or it may be a wash. :cry: we shall see, uh, feel, :wink: in a couple of weeks.





this is an italian 700c tube for general illustration


now, my tires are huge-volume by comparison, and run low pressures.
am sure I won't need to repump every day; more like weekly instead


older picture of the blue currie to show the generously fat not-stock tire
 
So, how are the tubes turning out?


+1 for the brake drag thing,
I'm afraid I too am guilty of only noticeing a ridiculous increase in drag through the DB. "Why is my bike only going 28, and why is the power usage so high?" Turns out, when I put the Vbrakes on the canti brake posts, I didn't clean or re-grease 'em. This worked fine in the basement, but out in the cold the movement got so pasty that the springs were too weak to really stop 'em from dragging.



BTW, you could try putting the battery back on the rack, but this time with the batter undear the seat instead of on the tip of the rack, lever effect.


Other question, the rims are 2.125 (about 1.5 inches wide) and tires 2.35 or so, right? How much room is left at the tightest spot?

Also, did you remove the fenders because they were too tight, or for looks?
 
Hi Francois,

-Fenders removed mostly because they were so tight a fit to the fat tires.
Looks better without them, but I miss the weather protection.

-Haven't done anything with the bike for the past few weeks; still on 24V.
-The rack, when I mount it, won't allow batteries on its underside; not enough room there. I might side-saddle them, though.

-Just installed the first latex tube last night. Put it on the front wheel because that's the easy one ((lazy lately)).

First impression: very favorable! I -think- the ride really does improve. I'm adjudging by shocks that come to the handlbars, to my wrists. It's silkier now. It pedals better yet. This -all may be placebo effect stuff- so, don't bank on what I say.

The tires are 2.5" wide, and on this frame, that's about as fat as can be fitted. I have no clearance problems at this width, but if there were wider tires available, I'd not be able to use them. I doubt most bikes can handle even the Big Hanks--they are relatively fat.

Anyway, the first impression is a GO for latex.
Bear in mind, anyone who may consider this option: they are presta valved, and of a natural material subject to deterioration in storage.
Latex can last decades, or be rotten from the start. Real rubber is a funny substance; it varies like the weather. I've seen antique rubber still behaving like new. And relatively new rubber can go to pot fast.

Light, oxygen, ozone, oil, petroleum solvents, combustion byproducts, etc, are enemies of rubber.
Let's see how my luck hold up with these latex tubes.
They seem to add suppleness to the ride.
They should be more puncture resistant too.

Such is the lore.

----
I'll get the rear one on soon. That's where I really want latex, cos on my bike, most of the weight is on the rear tire. Any reduction in rolling resistance at the rear will be bigger plus than what seems to have been obtained at the front. Eight miles is all I've got on her. Time will tell,
and though I may get enthusiastic, I know better than to rave over
-subjectively sensed- improvements.

Cheers,

Reid
 
Happy New Year to all.

I celebrate tonight with balloons instead of champagne. Heh.

These latex tubes are both in now, and -do seem- to improve the ride a bit,
but that's most likely the placebo effect.

It is astonishing to myself, to look at these thin, mint-green Michelin tubes,
and consider that they -might- hold up better than butyl tubes,
with regard to alleged puncture resistance.

Why, they are so relatively thin, and not oversized in crossection,
that when inflated inside my bike's fat, 2.5" wide slicks, they are really

uh, like balloons inside the balloon tires!
How can they possibly last?

Time will tell.
I can tell y'all this much:
It's not easy to change a rear tire's tube on the road.
So I had better not ever get a latex flat, orrrrrr :lol:
I'll pop a blood vessle in shame and disgust.

Thinking about now
about balloon-twisting clowns?


Yep, that's what I feel like--promoting,
riding on these things.

But, dang, they do make a silky ride...

I think, hell, I can't see it on Drain Brain, but...it's all for real!







:p What's that? Huh?







!


:wink:
 
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