What sprocket size are you running on your 2008 yamaha r6? I want to change mine to 55 rear and stock front. Don't know if that's a good choice for this bike? I found a lot of threads on this subject but I never got my awnser.

 

On my 06 R6r I'm runnin 14/56

 

What's your top speed on it with the 56?

 

Not sure on too speed. Only threw it on recently and haven't been on the highway with it yet. They say you lose 25% but a gearing like that probably more like 35%. It's about the biggest sprocket you wanna run if you still wanna ride on the street.

 

Read Dave Cutler's article on stuntbums.com. He's the man when it comes to stuntin yamahas. The R6r lacks bottom end power (but rocks on the top end), that's why I went with those size sprockets to get as much low end torque and still keep it on the street.

 

Yeah I've read that article. Andreas Gustafsson wrote on one of these threads befor that he adjusted the idle screw. I'm thinking of doing that on my r6r. I just need more info on it.

 

There is no idle adjuster screw on '06 r6r. You need an idle adjuster mod. Basically does the same thing. It's just a cable that you can turn one way or the other that you connect to throttle bodies to adjust your idle. It's a fairly cheap mod

 

When you guys say "keep it on the street", what speed are you talking? No one mentioned the speed range when changing the sprocket size. Thanks

 

I ride a 636 so take my advice with a grain of salt. Top speed shouldn’t be what you are really worried about. About 30% loss sounds about right with some of the aggressive gearing mentioned so probably about 120mph max but it won’t be quite the same. It may do it but it could be more prone to overheating and would be ripping in the rpm like you are going 170 with much less airflow. You will be high on the powerband cruising down the freeway and it’s not the most comfortable or quiet.