Rear light / brake light problem

[iwantazxr400]

Hi, can anyone offer advice? I replaced one of the two rear bulbs on my zxr400 L9 yesterday because it was only working as a brake light but not as a tail light.
Since replacing it I seem to have no brake lights at all, even on the one bulb that was actually working! Both bulbs now work as tail lights, but no increased intensity for brake lights. What could have caused this? I believe I have got the right bulbs, should I have changed both of them? I hope this is one of those "missed something obvious" problems as I have no idea about electrics!
Any advice welcomed!

[masterofinsanity]

sounds like an earthing problem, have you checked the brake lights from using both brake levers?

[iwantazxr400]

Ok, i have just had another look, having now changed both bulbs I have the brake lights coming on when I use the front brake. It appears it is just a rear brake problem, I have tried adjusting the rear brake switch but that has not worked.
Does this mean it still could be an earthing problem? Could I have dislodged a connector when taking out the bulbs? If so how do i fix that? Any ideas what I should try now?

[masterofinsanity]

if the brake lights come on with the front brake lever then i'd say your rear switch is faulty or needs adjusting.try pulling the spring attached to the switch see if th light comes on.

[iwantazxr400]

Thanks for your help, i will try that. Although the problem only started when I changed the bulb so I dont know how the brake switch has gone faulty all of a sudden...

[andyvanderpandy]

i noticed this week my brake light is stuck on. its defo the rear brake sensor so ive taken it off but i cant see how it ever worked!

theres the main body - a black cylinder, an internal spring, a moving rod inside and 2 connectors either side. i think im right in saying as the pedal lowers it pulls the centre rod down and it should contact the 2 plates, then the internal spring pushes it up and breaks the circuit.

but with what i took off, i dont see how it ever worked, have i dropped another part maybe?!!
it all goes back together but doesnt move very freely, and the rod definately gets no where near tocuh the connectors... or is it just that its so worn i need to replace it? :smt013

[masterofinsanity]

i bought a brand new one off ebay for £1.99, so i'd have alook a lot of them are the same, look here

[andyvanderpandy]

i bought a brand new one off ebay for £1.99, so i'd have alook a lot of them are the same, look here

i didnt realise how cheap they were! i ordered a new yamaha that look identical (but prob wont be!) for 4 squids! thanks for the tip.

[masterofinsanity]

i think the one on my gixer is off a zxr6 just had to use the old spring as the zxr6 was too long.