- A prototype in plywood
- Maintain the gaps between the wings of the template
- Zoom on the intervals between the wings of the jig
- Report the shape of the pieces on the pre-cut sheet
- Drill and weld the wings at the base of the hitch
- Adjust and drill the ball holder
- Shaping the hitch wings
A great lover of motorcycle trips, Gérard Vautrin first made a trailer. Then he designed a custom hitch: a discreet realization, which adapts to other motorcycles.
Costabout 60 €
Time: 4 to 5 days
- bench drill and locksmith tools (files, drills, taps...),
- arc welding station,
- grinder Ø 115 or 125 mm
Hitch a trailer to a large displacement engine, type " custom ", Poses little problem since the rear mudguard goes down quite low on the wheel. This perfectly matches the low height of a motorcycle trailer and makes the system more discreet: whether it is a classic coupling on either side of the fender, or internal tie As the one realized by our reader. Given the extreme variety of the current fleet of motorcycles, no industrial adaptive equipment specialist offers - to our knowledge - a coupling system ready to assemble. * It is therefore a custom-made equipment, made in very small series or individually by some dealers and personalization professionals.
* This article is from 2011
This is what prompted Gerard Vautrin to achieve a device as effective as aesthetic, since it is covered by the fender of his motorcycle. The coupling is not attached to the mudguard but to two arms Steel as solid as the frame they extend backwards. It is only on this condition that such an assembly can be considered, or even adapted to another motorcycle.
Without being extremely complex, this realization requires no less various tests and corrections before finding its final form: two boomerang-shaped wings, slightly arched inward. This is essential for the centering of the ball and the future road behavior of tandem motorcycle trailer.
A prototype in plywood
Superimposed, they are joined on one side by a short crossbar supporting the mounting plate of the hitch ball. Inherent in any realization of this type, tests and modifications are faster to realize on a prototype plywood (CTP) 5 mm thick, only on a sheet of 6 mm thick used for the real coupling. It has traveled some 15,000 km without any impact on the behavior of the machine or the strength of the assembly.
Maintain the gaps between the wings of the template
- Cut with a jigsaw, the plywood templates fit the interior dimensions of the fender: starting from the holes for fixing on the " arms Back of the frame.
Zoom on the intervals between the wings of the jig
- The gaps between the wings of the template are held by a cleat and three threaded rods threaded into tubes. The flexibility of the plywood makes it possible to respect the required dimensions without resorting to true bending.
Report the shape of the pieces on the pre-cut sheet
- The shape of the pieces is now to be transferred to the pre-cut sheet during the purchase. What simplify the other finishes, sided with the angle grinder and finished with the file.
Drill and weld the wings at the base of the hitch
- Carefully reported (using one of the templates), the Ø 8,5 holes of the fixings are pierced on the wings with a drill press.
- The wings are screwed onto the frame to determine the position of the bend before being welded to the hitch base.
Adjust and drill the ball holder
- This base must be perfectly welded because of the mechanical stresses undergone.
- The ball support is positioned and then adjusted before drilling so that the headstock remains clear of the mudguard.
Shaping the hitch wings
- After shaping, both wings must be perfectly symmetrical.
- The transverse reinforcements of the sheet metal fender make it necessary to rectify the edges of the wings in several places. Operation performed on the grinder and the half-round file.
- The hitch receives a coat of paint to protect it from corrosion.
- A fourth hole is drilled and tapped.
- It is equipped with a riveted prisoner nut that will mount the support of the plug of the harness.