Adapting Your Motobecane Throttle for a Larger Carburetor
Note: This guide is specific to the Motobecane 50v, although it may possibly apply to other Motobecane models as well.
Swapping out your stock Gurtner carburetor for a larger version such as a Dellorto 14/12 SHA or Dellorto 15/15 SHA is a common modification performed by many Motobecane owners. It is a relatively easy and painless procedure that will provide an instant boost in performance.
If you are switching to a Dellorto 15/15 SHA carburetor, one hurdle you must face is that the Motobecane throttle assembly on the handlebar is only designed to pull approximately 12mm of cable; this is not enough room to pull the throttle slide all the way open in your new carburetor. Fortunately, this problem is easy to fix.
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