It looks like every thing is fine and it should select the 988F-1.100.2160 as material variant in sales order. Can you make sure you are assigning exact same value you maintained in 988F-1.100.2160 to 1.002.9951 and i can see these are only 3 characteristic ( eqiipo, Masa_link , pedal) with 1 and then click on variant matching with that you will see list of material variant matching your input and you can select 988F-1.100.2160.
Please also check what setting you have maintained in "Configuration of Sales and Distribution -> Sales -> Sales Document -> Sales Document Item -> Define Item Categories." you can refer settings as i mention in my document prerequisite section Variant Configuration Material Variants : Creation,Usage in Sales order for replacing Configurable Material Part 1
Check and reply.
Thanks
Ritesh