Originally Posted by Vicks
Most of the Japanese litre bikes (R1, V-strom, GSXR etc) use the Shindengen FH020 R/R unit.
I bought mine from the local Yamaha dealer and found out that its used on all their 600-1000cc bikes (FJR, R6/R1 and several cruisers). The stock part is FH022 which has now been superseded by the FH020-AA with a new heat sink design. I posted the YAMAHA part number in one of my posts....
The FH020AA is the same unit they sell here. http://roadstercycle.com/
Only Roadstercycle sells it for $100, Yamaha wants over $200.
I got mine installed on the bike and the voltage never goes past 14.2V. Most of the time it's at 13.8V.