Review on SL Bicycle Tube Challenge by Shree Carmean

Almost all tire rolling resistance (CRR) tests I've checked on other websites have been tested with latex tubes. I've been riding my racing bike with "Mich" super-light inner tubes for a number of years. Now on my triathlon bike I decided to dive in and try them. The Challenge tubes are very flexible and both tubes I received weigh 65g each, 10g less rotational weight compared to the A1s I used. They're also lighter than the "V" varieties, which are slightly taller depending on where you find them. They were mounted on a used set of Pro3 tires that have put on about 1,700 rough miles. The rear had a few cuts in the tread but as a precaution a couple of cheap pre-taped patches can be used to stress the inside of the tire to keep the tube from expanding through the casing. The ride felt smoother and it seemed to take longer to roll off. The real test will be when I pair them with my race tyres, which only weigh 135g each. This gives me a low CRR and a total race/tube weight of 200g, which is lower than most tubulars on the market. I took a big nail and completely ruined the rear tire and tube. So a couple of replacement tubes were ordered to pair with the back of the Conti 4000s. Spring. Living and training on country roads tears a lot of rubber.