A Moto^pycle Bob 



VredericB. Hart 



Convert Your Motorcycle into 

 an Inexpensive Power Bobsled 



IX designing this motor-bob it is assumed 

 that the building will be done by motor- 

 cycle owners having limited facilities, 

 therefore everything is made in the simplest 

 form, of materials casiK- obtained. Except 

 the woodwork, nothing is required beyond 

 some pieces of i-in. gas-pipe, a small piece 

 of boiler-plate for the kingbolt support, 

 some 3^-8-in. outside diameter brass tubing 

 and steel wire for the ignition and throttle 

 controls, and some ^ g-'m- rod and heavy 

 strap-iron for the clutch-control and gear- 

 shift. Many dimensions will have to be 

 varied to conform with the motorcycle 

 used for the power plant, so only general 

 dimensions that are applicable to any ma- 

 chine are given, and c\en these may be 

 changed to meet the requirements of the 

 builder. 



Only a general outline is suggested for a 

 two-passenger seat and a hood for the 

 motorcycle. If such a hood is used it 

 should be open in front or covered with a 

 wire screen. Vents for windows in the 

 sides of the hood would be advisable. 



Frame Constructiott 

 The frame is constructed like the three- 

 point suspension used on automobile en- 

 gines, one point at each rear runner and the 

 other at the kingbolt. The frame sides A, 

 Figs. I and 2, are made of oak or other hard- 

 wood, 4>< in. wide, iM in. thick, and if the 

 details of the drawings are adhered to, the 

 length should be 9 ft. 9 In. The rear 

 cross-member B is 30 in. long, 8 in. wide 

 and 2 in. thick. There is a second rear 

 brace C directly under B at the extreme 

 end of the frame; this is 30 in. long, 4 in. 

 wide and 2 in. thick. From this point the 

 frame is somewhat narrowed, principally 

 for appearance sake, and the front cross- 

 members, E and F, are 24 in. at the forward 

 edge and slightly tapered to conform with 

 the lines of the frame sides. The cross- 

 member £ is 5 in. wide and 2 in. thick and 

 the piece F is 2^4 in. wide and 2 in. thick. 

 At the center of the piece £ is a block G 

 5 in. long and 2 in. thick, and with a width 

 ecjual to that of the distance between the 

 fork-ends on the motorcvcle. Further de- 



Plan view giving a general layout for the 

 parts, frame and steering arrangement 



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