Here are the definitive details about the throttle mods.
I couldn’t find accurate info in all the threads about R1, R6 so investigated myself.
6 months ago I ordered an R1 throttle, didn’t notice a huge difference but a little.
Now have just fitted R6 throttle and there is a huge difference right away. A lot easier to get WOT without moving hand up or creeping.
2007 GSXR 600.
Diameter of cable pulley: 33.5mm.
Part: 4YR-26240-02. Could be different for other countries.
Diameter of cable pulley: 36.5mm.
The ring/washer that comes on the throttle can either be cut off/left outside the housing or trimmed down in diameter so is flush with the part that cables wrap around. Other than that it is plug and play. I trimmed the ring down and had it inside the housing, this made a snug fit without any sideways movement.
Part: 2CO-26240-00. This number is what was on the yamaha part label on the bag the tube came in. Some people in the USA are saying their # is 2C0-26240-00-00 (extra 00).
Diameter of cable pulley: 40.5mm.
For this throttle to fit inside the housing, part of the lower housing needs to be removed with a dremel. Once this is done it fits perfectly. This part also comes with a ring/washer, it does not need to be modified because of the change to the housing. Again I left the ring inside the housing for a closer fit and to stop any side to side movement.
With both throttles I have had no problems and no binding or sticking, snaps back like the original part. The amount of plastic I removed from the housing was about 4 or 5 mm but just keep test fitting the throttle until it fits without touching, dont worry about the screw hole as we you wont remove enough plastic to get near the screw. The years above are what I asked for when ordering, I’m sure other years will be the same but I don’t know what ones. Ordered from official Yamaha dealer here in New Zealand.
Both R1 and R6 throttles are slightly smaller in length than the GSXR, this left a small gap at the bar end.
Procedure for removal (for pics see other thread [DIY] R1 Throttle Installation (no 56k)
Fully loosen the throttle cable adjuster to get as much slack as you can.
Remove bolts holding each half of the housing together.
Split open housing.
Turn throttle to wide open and remove closing cable (closest if sitting on bike), then you can easily remove the opening cable.
Now just remove bar end and slide off throttle tube.
You can dremel the housing while on the bike but to ensure I didn’t scratch or screw anything up I removed it completely so I could work on it. To do this:
Remove screw and bracket holding throttle cables into lower housing. Take cables out of housing.
Unscrew white plastic covering starter button, then remove screw holding button in place.
Snip/cut cable tie holding wires to housing and its free.
Reverse order to put back together.
Whole job took 15 mins start to finish.
See photos below.