Sunday, February 22, 2015

Saturday, February 14, 2015

Schwalbe Thunder Burt. Initial review

In keeping my Giant Carbon XTC 29er in lightweight XC trim I decided to try the recently released Schwalbe Thunder Burt on the rear. I haven't actually ridden the Thunder Burt yet due to the crappy weather here but I'll give my initial observations and give a ride report as soon as the winter tones down. I've been using the Schwalbe Racing Ralph 29 X 2.10 in standard trim which Schwalbe now calls "lite skin" which weighs in at 495 grams. I find the tread wear is very acceptable but the sidewalls cut very easy. Running tubeless with Slime as a sealant has helped unless the sidewall "slashes" which can be an issue with these lightweight racing tires. The "snake skin" version of the Racing Ralphs weight in at 585 grams which while still light does add 90 grams. The Thunder Burt in lite skin form comes in at a feathery 435 grams and the snake skin at 515 in 29 x 2.10 sizing. With the added protection of the snakeskin and only adding 20 grams compared to the standard Racing Ralphs I definitely went in that direction. Schwalbe also makes a "race guard" version for the Thunder Burt that weights 490 grams but to my understanding it's only added puncture protection is along the center of the tire not the side walls which is what the snake skin is all about. I have yet to puncture badly enough along the tread area so the snake skin was the logical choice. Upon laying my eyes on the Thunder Burt's for the first time and not just a picture I admit I was a bit skeptical as the center tread or lugs are tiny.... I mean really small compared to the Ralphs. My first though was any mud or soft ground and I'm not going anywhere, though in the dry these tires are going to be fast, very fast. I've read a few other ride reviews that said while their tricky in the mud they are surprisingly much better than you'd think. In tubeless form and lower pressures some of this can be offset. I've included a photo comparing the 2 tires next to one another. The Ralph is mounted while the Burt is not but you can get an idea regarding the lug design. When I really did a close inspection and counted the lugs in a 2 inch square area (5 cm) the Ralphs have approximately 19 lugs while the Burt’s have 36. Even though there smaller lugs there are considerably more to offset the grip issue. Ride review to come.
Even though the lugs are much smaller on the
Thunder Burt there are many more lugs per square inch than
the Racing Ralph. Rolling resistance is very low making this
a very fast tire.

Saturday, February 7, 2015

Performance in pro cycling

Ever wonder what separates pro endurance athletes from their amateur counterparts? First of all there's of course time to train. Working for a living and training requires the delegate art of balancing time. Beyond that here's the most notable differences in the physiology of top pro endurance athletes when compared to amateurs.

Interestingly, multiple studies show peak VO2max values are not that much different from non pro athletes, then again as I’ve written about in the past VO2max is quite genetic and can only be trained or enhanced about 10%. Seasoned pro's separate themselves during submaximal efforts. Importantly, lactate threshold profiles. Pros can maintain power levels upwards of 90% of their VO2max in comparison to around to 80% for amateurs. Even at these higher levels pros can sustain these levels longer and can still utilize some fat for fuel while nonprofessionals at 80% burn through their carb stores at a higher rate. Amateur's also have a more rapid rise in oxygen consumption at threshold.

The translation of all this means pros have more resistance to fatigue and greater efficiency allowing them to train day to day at higher intensities. All this is more centered around cycling due to
the measuring ability of power meters but the physiology is still the same for any endurance based sport.