Engine Vibration/Front countershaft sprocket questions!

Hello everyone. I am hoping that someone can help me out . I have searched the threads, and can't find any answers. First of all, I have an 07 RWB that I have done the following mods too: Catless OEM header, Power Commander with Coyze's map, flapper valve, snorkel, O2 eliminators and today, -1 on the front sprocket. My first problem is a engine vib that is very rpm specific-it comes on at 4600 to 4800 rpm. It is not speed related, but it is more prevalent in 5th and 6th gear. I have checked everything I could think of fastener wise, and can't find anything loose. This was evident before the install of the Power Commander, and the PC made no difference. I am sure it is the motor, as at speed, I pull in the clutch, and coast, and it goes away. Any ideas?:crazy: My next question is in reference to the installation of a 15 tooth countershaft sprocket. When I installed the new sprocket, and torqued it up per the service manual, I still have maybe 1 or 2 thousandths play. Anyone know if it is supposed to be like that? I rode it for about a hundred miles today, and all is well. I'm just curious if anyone else noticed anything like that when they were installing theirs. Thanks in advance.

 

My guess is maybe the chain is tensioned too tight causing the normal vibrations of the V engine to travel though the chain and chassis. I used to have that problem right after a tire change on my old ZX6 ninja, damn shop tensioned the chain too tight and it caused vibrations throughout the bike, once i loosened it a little it went back to normal.

 

Thanks, Viffer Rider. I am going to head to the garage and loosen the chain a bit, right now! I will let you know if that fixes it.

 

Check to make sure you have no tight spots in the chain too, sometimes the chain gets tighter/looser in some spots in the rotation. Rotate the wheel in different spots and check for chain tension in 4-5 different spots to ensure consistency.

 

Does on off power make a difference?

 

Update: It was the chain, but not that it was too tight! It had some kinks from build up of chain lube (sticky stuff). I cleaned the chain with some 80wt gear oil, and the vibe was gone. Thanks!