Size table: 
				
				
										
						
															
	
		
													
						
					
					
				
			
			 
		Adapter code 
			Head tube outer size 
			Length between the front of head tube and the back of the welding of top and down tube connection (See the picture!) 
		
			 
		A1 
			3/4" 
			0cm and have 2 cm free space between top and down tube 
		
			 
		A2 
			1" 
			0cm and have 2 cm free space between top and down tube 
		
			 
		A3 
			1 1/4" 
			0cm and have 2 cm free space between top and down tube 
		
			 
		A4 
			1 1/2" 
			0cm and have 2 cm free space between top and down tube 
		
			 
		B1 
			3/4" 
			0-9 cm 
		
			 
		B2 
			3/4" 
			9-12 cm 
		
			 
		B3 
			3/4" 
			13-18 cm 
		
			 
		B4 
			1" 
			0-9 cm 
		
			 
		B5 
			1" 
			9-12 cm 
		
			 
		B6 
			1" 
			13-18 cm 
		
			 
		B7 
			1 1/4" 
			0-9 cm 
		
			 
		B8 
			1 1/4" 
			9-12 cm 
		
			 
		B9 
			1 1/4" 
			13-18 cm 
		
			 
		B10 
			1 1/2" 
			0-9 cm 
		
			 
		B11 
			1 1/2" 
			9-12 cm 
		
			 
	
B12 
			1 1/2" 
			13-18 cm