Can't speak specifically for the Roadstar, [mine is carbed] but I've dealt with plenty of fuel injected motors over the years and there a few common issues that can cause performance problems, especially rough idle. Even if you think your bike is running well, you should do the first two of these at least twice a year, as preventative maintenance. More often if you ride more than 12k miles a year.

Frist is the Air Mass Sensor, also referred to as the Mass Air Sensor or Mass Air Flow meter [MAF]. The sensor gets dirty after a while, *especially* if you're using a K&N filter. The red oil you spray on the K&N filter, after cleaning, can foul the sensor if you use too much. Also, if you run an aftermarket air filter housing, you don't want to vent the crankcase to the filter housing for the same reason, unless it's *after* the MAF. Pick up a can CRC MAF Cleaner. DO NOT USE CARB CLEANER!! Carb cleaner will leave a film on the sensor and make it worse. The MAF Cleaner works great and can make quite a difference.



Next are the injectors; the nozzles can get clogged over time. Pick up a can of Techron and run it through a few tanks.

The other is the oxygen or O2 sensor, [sometimes referred to as the Lambda Probe] they do go bad after a while and will cause problems with the fuel mixture. They need to be tested with a multimeter to determine if they've gone bad.

Here's a video demonstrating the test procedure for the single and triple wire probes to give you an idea.



Beyond that, if none of those work, check your fuel pressure regulator, fuel filter and pump. Also, don't' forget the obvious stuff like clean air filter and fresh plugs.