rolling resistance

Technical Q&A with Lennard Zinn – That stubborn bead

Dear Lennard,
Why would changing a tire on a Zipp 530 be so difficult? I beat my fingers and snap tire levers trying to get a tire off.
Steve Dear Steve,
It’s a good question, but one I thought might be best answered by the folks at Zipp.

Technical Q&A with Lennard Zinn – Tire talk

Tubes, tubulars or NoTubes?
Dear Lennard,
I'm currently running Campy 10-speed and am interested in running Hutchinson Tubeless Tires. It appears that the only officially approved system is the Shimano Dura-Ace wheelset, which is obviously not an option for me. My question is will a wheelset with rims that do not have pierced spoke holes on the interior (like the Mavic Ksyrium SL, Campy Shamal Ultra or Fulcrum Racing Zero) suffice and is there anything special that has to be done to make them work?

Technical Q&A with Lennard Zinn – Rolling resistance

Dear readers,I’ve been wanting to write about rolling resistance for years, and I’ve had ongoing e-mail conversations with a number of you on the subject. Indeed, I’ve built up enough of it to compile a collection of some of the most interesting.Lennard WaterDear Lennard,As I was riding though an unexpected rainstorm, I noticed that, even with the rain, it seemed to take less effort to ride on the wet road than when it is dry (all other things – especially wind and temperature – being constant). I know that there is less friction when it comes time to stop or to turn. Could it be possible

Technical Q&A with Lennard Zinn – Staying warm; What pressure is good pressure?

Keeping important parts comfyDear Lennard,This isn't a nuts and bolts question, but I thought you might shedsome light on this subject. Most roadies I know (including myself) preferto wear bib shorts with leg warmers instead of tights in cold weather.I can't understand why nobody makes a short with a windproof panel in thesensitive chamois region. Surely I'm not the first to think of this.JayDear Jay,Good question! No, you are certainly not the first to wonder this!Here are somewhat contradictory answers from De Marchi and from Sportful,which also owns Castelli.From De MarchiDear Lennard,The

Technical Q&A with Lennard Zinn: Tire pressure and rolling resistance

Dear Lennard Zinn;Is it true that the Zipp clincher 404/303s will break up when tire pressure exceeds 140? --JV Dear JV;Below is a long answer to your question, but it is worth reading, as it addresses, in addition to the specific Zipp question, the general question many of us have about how much pressure a clincher rim can handle.--Lennard Answer from ZippDear Lennard and JV;In short, no, a ZIPP 303 or 404 clincher will not break up when tire pressure exceeds 140psi. The source of this concern may stem from one or both of two sources: either from the Maximum psi sticker ZIPP now applies to