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Techs-Mechs: Tommeke's Troubles


We all watched it.  Tom Boonen helpless on the cobbles of the Arenberg Forest waiting for a teammate or support vehicle so he could continue.  A later crash kept him from being part of the selection but he burned a lot of matches along the way, so one wonders how much he could have done had he made it back to the Cancellara-Hushovd-Ballan group.  So what happened?

From what I have been able to gather his chain popped off as can happen on the bumpy stones but rather than "shifting" it back on while pedaling, or jumping off and snapping it back by hand, he was stuck.  He was using a chain watcher which is a small alloy rod that clamps to the front derailleur clamp and acts as a safety bar to keep the chain from moving too far inward.  This is nothing new, and probably the majority of the riders yesterday had them on but in this case it obviously failed him.  

One drawback is if the chain finds its way between the chainring and the chain watcher it can be very difficult or even impossible to pull the chain back on to the ring.   It's designed to fill the gap between the ring and frame, but this can work both ways as Tom found out yesterday (or so I believe was the case).  The 11 speed ultra narrow chain must have  squeezed it's way through the gap, aided my Tommeke's poweful pedal stroke.  I'm just speculating. Regardless, it was jammed in there so well that Tom had to wait for help.  

Tom was using a 53/46t chainring combo.  The course is a big ring ride the whole way but guys use 44 or 46t inner rings, not so much for a "climbing" gear but to catch a chain easier if it pops off the big ring easier than a 39t would.  Are the chain watchers really overkill?  

I also read at CN that he had another issue with a bottle popping out of the cage and finding itself wedged between the frame and the rear wheel.  A freak occurrence but it was that kind of day for Quickstep.  Tom was using a Tacx Tao aluminum cage.  These are pretty common cages on the pro circuit and I use a pair myself on my road bike, but they aren't super tight.  The bottle sits down in there pretty well but there is no tension like in the more common (for the cobbles) Elite Cuissi Gel cages or the very simple but tough Arundel stainless cages used by Garmin.  Tacx Taos when used on the cobbles are usually enhanced a bit with some grip tape or rubber strips.  Was Tom using just the standard model?  Ok, I'm splitting hairs here, and it was a freak bounce for the bottle to wind up where it did, so I'll cut the Tao some slack.

Winners for the day would be Cervelo bikes and the modified R3 used by Van Summeran and Thor.  The modifications were longer fork and more rake as well as longer stays for a longer wheelbase and larger tire 
clearance.  The Mavic 25mm wide carbon M40 wheels had a pretty nice debut at Roubaix too with the victory.  

Would love to hear your thoughts on the Tommeke mechanical as well as any gear that impressed you during the cobble season.