LED taillight bulb

Can i install a led taillight bulb without any modifications? 1985 XJ 700 n

 

That is an independent ckt, and you should be okay to install a LED no issues.

 

Does the fact that it also serves as the stop light make any difference?

 

I am not too sure what you are asking? Are you going to change out the entire tail light to a LED? Are you just changing out the bulb to a LED? If you are just doing the bulb, "supper bright LED" has a sight that will cross-reference and bulb to a LED.

If you are just doing the bulb conversion, you will have to make sure the LED has the ability to increase the brightness when you do either brake activation. I hope that helps clear it up.

 

Just the bulb replacement. I am hoping that the LED bulb will be a little brighter and also take less power. When I hit the brakes at idle the front light dims. At one time in the past hitting the brakes at idle would cause the engine to shut down. I replaced the alternator brushes and that solved that problem, but I still don't like the big drain.

 

Have you checked with a multi meter the DC voltage across the battery at idle and then let's say 3k rpm? You might not be charging very well, if at all while at idle. You should be getting close to 14v DC when you are at 3k rpm.

If you start to change out shared lights like the turn signals, you will start to have some issues that will require some extra steps. It is nice to go to LED, but with our older bikes it takes a little extra work to make them functional will the LEDs.

 

I have in excess of 14 volts at about 2000 rpm. It appears to me that a LED 1157, which is a dual purpose bulb, should work just like a standard 1157, but use less power.