Need to install brake light switch to XR250R

I have a 1990 XR250R and need to turn the tail light into a brake light. I found a description on how to do this for a XR400, but didn't know if it would be the same for my bike. Does anyone have directions on how to do this on a bike like mine or know if it is the same. I am looking at 2 different part numbers. One is a Dennis Kirk p/n 21-0369 (10mm x 1.25mm K&S hydraulic brake light switch) and the other is also a brake light switch from A.H. MacLaughlins p/n 44-0077. Any help would really be appreciated!

Used to have an XR250 before it got stolen. I'll try to remember how the brake light went. They are the same as the XR400 so follow the article. The XR socket and bulb have dual elements, but it's not wired. I took the socket apart, soldered a wire to the unused connecter in the socket. The switch I used was the type that bolts into the top of the master brake cylinder. There are several on the market, they're all pretty much the same. I've forgotten how the wiring went, but the article should get you going in the right direction. One side of the switch ties into the positive going to the rear light, the other goes to the wire you soldered onto the extra connector. Solder all connections and when it's done, silicon seal everything. Hope this helps

the K&S switch sounds right i have those on my bike, the same size fits the front master cylinder as well as the rear.I've had mine installed for just over 2 yrs they've held up quite well.

There is a guy on ebay that sells them thats where i got mine they were like $14 a piece. ( peak something its called he has an ebay store)As for the light , if you take the xr250 or 400 rear light apart you will see there is a spare empty spot for a contact point, remake this contact by interting a sm tab as the other one and you now have a stop light assembly which works fine.You can now use an 1157 type of light

The other solution is to insert a resistor inline with the present single element setup and as you apply brake it shorts out the resistor making it brighter. This is a very common method for those who dont want to change anything.


Can i get a link to this article?

If you had the 1996 and newer XR250, then it would be the same, i.e. the newer bikes have the bigger lens and the 1157 style socket that only needs the added wire. But you have the 1990 XR250, which has the smaller tail light (as found on the XR600R and XR650R). These have a single filament bulb socket with the small 3W glass bulb. There is enough room in there to tuck a similar socket underneath and add a 2nd bulb of higher wattage (12 or 16W as found in many cab mounted brake lights on small pickups (e.g. Ranger). Or you can change out the socket entirely and add an 1157 style socket with a mini 2 filament bulb (I forget the number for them -- just think of an 1157 in a smaller round glass envelope.)

As for the hydraulic brake switch, I am sure the thread for the older and newer bikes is the same. Just make sure it is for a Nissin (or whatever the name is) master cylinder.

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