I have a 2005 cbr 1000rr that was in a wreck and I rebuilt most everything but the rear brake is always on when the key is on, I have pulled it apart and tried re-doing the connections but the tailight is a different one then the stock one just due to the wires are different colours and no matter what combination I try the brake always stays on. the wires on my bike should be Green, Green/Yellow, and Brown/white. but the ones on the tailight that is on my bike is Black, Black/white, Black/Yellow. anyone got any hints of anything that I can try?

 

sounds like its not a problem with your tail light. seems like a short from your front break lever sensor or rear brake pedal. unplug both of those and see what happens, then plug them back in one at a time and let us know what happens.

also, have you replaced the break lever or master cylinder or anything like that?

 

I have replaced the Front brake lever, Master brake cylinder, the black switch located under the maste cylinder and the rear brake pedal. I had all the fearings off the bike and checked the wiring system and didnt come up with any pinched or shorted wires. I sure wish I knew more about electrical so I could figure this out and ride my baby without worrying about having issues.

 

I would get a test light. They are cheap at an autoparts store. Ground the ground lead out and see what wire gives you power without your brake engaged. If you get two wires that give you power without your brake engaged, then you have an issue with your bike. If only one, then the issue lies with your connections and you need to swap your connection around.

If two wires light up, unplug your front brake switch and recheck. Then, unplug your rear brake switch and check. If two still light up.. I have no idea.


Im thinking you have your running light hooked up to your brake light side of your taillight. They should be black to green, Green/yellow to black/yellow, brown white to black and white.

 

Could be something as simple as readjusting the brake switch (black plastic), especially if the brake lever position has been bent/adjusted. Or the thin wire loop that hooks through the top of the switch has broken or become detached.

 

I ended up ordering a new intergraded tail light seeing as mine was cracked and needed to be replaced. so I will install it when it gets here tomorrow and see if I am going to have any problems with the wiring. thanx for the help guys. ill let ya know how it turns out.