the other motors (engines) are better for big power builds but the r1 is period the lightest and narrowest of them all. electronics are simple and its only 4 lbs more than the 700r motor 138 vs 142 lbs gsxr 1000 186, busa 228, hon.1000rr 183, stock its only 142 to the ground pretty good for a 430lb quad.
ps. there is a bolt in 4.6 gl rear tank with no interference and extended travel