Yes

I think Haycraft put it best
"How fast do you want to be?"

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@christopher_borden •
Spinning Spoke • Dimond Bikes • Flo Cycling • Castelli Cycling

Can someone explain how/why the tube material makes a difference? How much of a difference does it make?

the more supple the material the easier it rides over tiny flaws in the road. A stiffer material takes more of your energy to bend or deform.
so if you add up all the millions of tiny deformations that a tire is experiencing it all ads up from the worst to the best combo of tires and tubes
it can make big difference. it can easily be in to 10-20 watt range and if a fairly good IM ride is burning 200 watts, 10 of those wasted on your tires and tubes is massive.

Latex is more supple than butyl. In the same way that more supple tires will roll faster than harder ones, tubes are the same way. Granted, a latex tube combined with a very hard tire won't perform that much differently. The more supple your tire/tube combination is, the better it can absorb imperfections in the road and thus reduce rolling resistance.

Not sure on the exact numbers, but somewhere in the range of 1-5 watts per wheel. Even if it was only 2 watts total, that's still not too bad when you consider two latex tubes only cost $30. People spend hundreds of dollars on ceramic bearings that *might* only get a fraction of 2 watts.

Best Bike Split allows you to change between butyl and latex in their calculator. I checked an IM course a while back and the difference between butyl and latex was 7 minutes. I think I had an FTP set at 200 and riding at 70% FTP. That power was an estimate as I didn't have power at that time.

Sorry to hijack this thread, but am also curious about any thoughts on just installing the latex tubes on one tire? Is the benefit of latex greater in the front wheel or rear wheel?

Yes, latex is great. They do hold up if they're installed correctly. Add some baby powder to the inside of the tire, coat tube with it, make sure there aren't any kinks, and check the tire bead to make sure the tube isn't pinched and you'll be fine. It's really not different than a butyl tube installation, but the latex is more supple and slippery, so folks have a tendency to goof it up.

The ride is fantastic, especially when paired with a nice tire like a Veloflex.

i think bestbikesplit was about 6 minutes for me if i remember correctly (IM distance)

The benefit is slightly greater on the rear wheel since the rear has higher rolling resistance (due to having more weight on it).

That being said, if you have dedicated race wheels, definitely use latex on both f & r. It's some of the cheapest performance gains you can get, and it makes improves the feel of the bike (comfort, etc.) as well.

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ECMGN Therapy Silicon Valley:
Depression, Neurocognitive problems, Dementias (Testing and Evaluation), Trauma and PTSD, Traumatic Brain Injury (TBI)

Thanks for the several good answers here!

So im planning on getting the continental grand prix 4000s II.

Whats best as far as width goes? 23mm or 25mm? My Main goal is IM racing

What wheels?

Zipp Firecrest 808's

23c in front for sure. Personally I use a 23 in back as well, but some folks (Rapp, etc.) opt for a 25 (slightly less aero but faster rolling, and more comfortable).

My vote would be dual 23c. I'm 185 and can't see needing a 25c rear, especially with a great tire like the Conti.


Ref: I train on a road bike with a 50mm/90mm deep wheels and 23mm GP2000s on f&r. I race on a 90mm front/Disc rear with 23c Conti Supersonics (a faster tire, but less flatproof than the 4000S).

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ECMGN Therapy Silicon Valley:
Depression, Neurocognitive problems, Dementias (Testing and Evaluation), Trauma and PTSD, Traumatic Brain Injury (TBI)

23mm is a safe bet.

You don't need to add baby powder (or talc, etc.) but make sure that the latex tube has enough air in it to have shape before installing.

Can someone explain how/why the tube material makes a difference? How much of a difference does it make?

Makes a lot. It isn't suppleness, it's hysteresis. Butyl absorbs a lot of energy when it flexes and latex doesn't. Amounts to around 5 watts typically for both wheels.

Latex is used for slingshots and spear guns because of this. Try that with butyl and see what happens.

I use latex tubes all the time and never have a problem. Just make sure you use some sense and talc when installing them and you'll be fine. If you glued your own tubulars, this will be comparatively easy.

Just the usual caution re using latex inner tubes with carbon clinchers and undertaking prolonged descending..

Latex melt more readily than butyl.. ie blow outs...

A non issue for flat land riding..

Yes, it's a no-brainer for racing. I'm always astonished when I find anybody even slightly serious about their training and equipment who doesn't race on latex. I'm also astonished that my local bike shop, which sponsors a racing team and a number of triathletes, and is generally acknowledged to be the go-to place if you want to drop a lot of money on a bike and get good advice and fitting, never seems to have latex tubes in stock. Have asked on a number of occasions and had to go online every time (other LBS are even worse, they don't even seem to know what a latex tube is, but will happily sell you a ten grand bike).

For me the comfort factor on a ride as long as IM probably provides at least as much improvement to my overall time as the reduced rolling resistance does.

I would guess better in the rear wheel, as its carrying most of your weight ish

Now I'm on the hunt to find some latex for my Flo 60/90. I have an 80mm valve up front and 60mm with extender on the back.

VERY noticeable difference!

Latex melt more readily than butyl.. ie blow outs...

Zipp measured this and found that the rim strips melted before the latex tube. I'm willing to bet it's never happened. A tube isn't under any stress if it's in a tire and properly installed, so it can't "blow out"..

Some manufacturers advise against latex but it's probably a CYA move because so many people suck at installing them.

Nobody I called in the Denver/Boulder area (performance bike, bicycle village, colorado multisport, wheatridge cyclery, endurance house) stock latex tubes - hence the reason I still run butyl in my nice 330 TPI tires.