Carre Bertin C 37 Restoration Update

As you already know, a bicycle , typically, does not remain static unless it is a wall hanger used only for display. As cyclists, we tinker with our bikes, adjusting, substituting, modifying to adjust to changed circumstances, uses and needs. When I completed my Carre/Bertin C 37 restoration in 2014, I didn’t know it was a Carre built frameset but I was reasonably sure it would remain fairly static in its presentation. The just completed bike is seen in the photo below:

Carre/Bertin C 37 Oct. 2014

Since then, small changes have been made. I added toe strap buttons to facilitate tightening the toe straps, replaced the now, worn, dirty and faded red bar tape with more of the same colour from Tressostar, fiddled with saddle placement height and added the usual tool kit necessary for road riding. The result is this photo from a few days ago:

Carre/Bertin C 37 Dec. 2018

As well, there has been some curiousity regarding the drivetrain gearing. As mentioned in the original restoration series, the rear hub is a Maillard Helicomatic, a conventional style freewheel with an unconventional helical attachment screw thread. It is not a cassette as the hub bearings are

Rear Helicomatic Hub and Freewheel

discreet from the freewheel’s bearings which are in a separate body and not integrated with the hub. Details of this uniquely French system can be found at the Helicomatic Museum. This hub has a 120 mm over locknut width dimension which is the size of the now obsolete 5 speed conventional freewheel dimension for rear wheel dropout spacing. One other unusual aspect of this freewheel is that it is not a 5 speed as one would expect in a 120 mm spaced hub but is actually an Ultra/Compact narrow spaced freewheel instead with 6 cogs where 5 normally reside. Tooth configuration is standard period Maillard


and it uses a Sedisport black chain. And it shifts very well over its medium range cogs. The freewheel itself is 14-15-17-19-21-24T in sequence and since my area is relatively flat, it works just fine. The Helico is paired with a Stronglight 93 double crankset with 52/40T rings which is a big improvement over the original 45T inner ring the crankset came with. The 12 tooth difference is easily handled by the Simplex SLJ A522 front derailleur.

Likely the next change will be to replace the Mafac LS2 brake pads but as further changes occur, I will update the blog with an appropriate post.