the motor on the DS has always had 2 plugs since its intro in 2000.

the hp difference on new model years is due to lightened drive train, less mass on axle, more rigid and non-collapsing air tube from airbox to carb, and a thing or two more I am forgetting right now...

 

OK, I thought they switched to one plug for 2004 and maybe 2003.

That must have been a trial and error change for BMW F650 EFI (only) that didn't work like cams, higher compression, and continuous programming changes that still doesn't solve lower powerband flat spots. They have tried everything almost except gravity or inclined manifold delivery, the expensive redesign option Sachs proposed in 2000. They keep trying to make it work while saving more money too, I have to give them credit.

 

My DS was made 04/2004 and has the two plug head

 

Yep,

I believed Hightower when he said it, but verified it anyway since wanted to understand better.