Ok,
I have an update that may help...........or not?
I have recently ordered BOTH, the R1, and the R6 throttle tubes from 2 different companies.
It SEEMS as tho, Yamaha is only using 1 part now, for both part numbers.
I had a left over R1 tube that was still in the package, so I ordered an R6 to compare.
IDENTICAL!!!
Thinking that Ron Ayers might be shipping the wrong part, even tho the part numbers coincide,
I ordered another R6 tube. AGAIN, IDENTICAL!
Now I have an R1 tube, and 2 R6 tubes that are with their respective packages, and all 3 are the same, so I order from another vender. The package came in today, and guess what??
It's IDENTICAL to the other 3 that I already have. I measured everywhere there is to measure, with a digital caliper, and there is NO difference.