2008 EXC-R Headlight/Tailight dim out

My excr headlight & taillight will be on when I fire her up, then they will both fade out together, at the same time, then come back on, then off again, trying to figure what could cause this, anyone have any ideas? 

If you want to really be able to see at night you might want to look into ditching that OEM headlight, it's pure junk.


But on to your problem....I didn't have any of those issues so I'm just throwing stuff out there.  



I'm pretty sure that the OEM setup runs off the stator but I would check the ground connections on the battery and make sure they are clean and solid, also check the positive while you're there.


Did you check the wiring and the connections to the lights and the sockets where the bulbs sit?    ...I'd pull them apart and clean them as best you can. 

Get a volt meter and check the voltage going to them (headlight is easy access) and see how it varies from idle to rolling on the throttle a bit.  

Yes, I checked the connections to the lights, & I did clean them, I will check the grounds & the positive next. Its just odd that they both go in & out together at the same time. I know its not the battery because she fires up with the e start just fine. Either way, thanks for your thoughts.


And the headlight I have is an aftermarket bulb which is alot brighter than the stock one, but I am definitely looking into an aftermarket headlight assembly, like an Enduro Engineering one. Thanks again for the manual.

I have that same bulb, they actually sent me two of them when I bought from sicass racing!  It's still very very poor.  The problem IMO is that reflector shape and housing is just a bad and inefficient design.  It seems that the main concern was integrating the look as opposed to function.  The BD light is worth it if you can swing the dollars, and you can add another chunk for the dimmer if you want to stay street legal....I didn't bother.


The fact that's it's both would lead me to think it's a ground, not necessarily the battery but start there and work out.  You can look at the wiring diagram and try and see if the two lights grounds meet up before connecting to the ground, I'd guess it does somewhere and that wire might have a crappy or corroded connection or compromised in some way.  


Get a multi meter and see what voltage you are getting at the light(s).  

Do the turn sigs work okay?


Any success?

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Similar Content

    • By Ponch
      I have a 2007 450 EXC that I recently installed a new clutch slave cylinder on. Per the 2007 KTM service manual it clearly states that the clutch needs to be filled with hydraulic oil, which I did (magura blood). That was yesterday. I went out to double check the level today and when I removed the cover, the rubber seal was all contorted and out of shape. I then looked at the cover and it's a Brembo clutch and says "DOT 4 brake fluid only".
      I flushed the line and the master cylinder about 7 times with DOT 4 brake fluid and there was no sign of the magura blood left in the system. My question is: other than the rubber boot on the master cylinder, what damage might have been done by putting in the hydraulic oil? It was in for about 24 hours.
      Thanks in advance for any advice!
    • By pumpernickelBrad
      Hi Folks!

      Sorry if there are a bunch of threads already but I used the site's search function and didn't find anything so far...

      I just found a decent deal on a '14 350 EXC-F with 11k km (unknown hours). Has a few goodies including skid plate, hand guards and it's for sale for about $2k CAD less than a '16 with 6k km on it.
      The bike is in showroom condition (appearance) with no indication it has been offroad at all.

      What would be the gotchas that would make this deal realistic? I'm coming from a WR250R where the engine lasts forever, is 11k street kms high for these bikes? 
      Are there any big defects in the '14s that I haven't dug up yet?
      With no service records what things should be done, checked, etc?
    • By Brannnt
      I purchased an '06 525 EXC some time ago, and recently pulled the motor out of the frame to address some other issues. When I removed the clutch slave cylinder, I noticed an issue the previous owner neglected to tell me about during the purchase.
      It appears that at some point, the chain broke and damaged the engine case near the clutch slave cylinder (see pics, please). I have noticed that the clutch does not fully disengage (bike lurches a bit going into gear, neutral is hard to find... its worse when engine is cold) ... I did not notice any leaks around this area (mineral oil or engine oil) before or during disassembly. 
      The previous owner (or someone) repaired it with some sort of epoxy.
      Without doing my due diligence (checking clutch fluid level, bleeding) I hesitate to state that this is the cause of my clutch disengagement issue ... but pardon my ignorance here and help me out: How bad is this?  Am I looking at replacing my engine case here or is the previous owner's jerry rig good enough?

    • By Black Sox
      Just bought a new 2017 350 excf ,will be doing 98% off road ,ordered skid plate bark busters ,
      my ? Is what's the best easiest way to eliminate rear fender light assembly.I still would like to have a break light.
      xcf fender will fit so dealer says,under $50.00 👍But xcf brake light $125.00 .👎What's the best economical way of doing this?
    • By JNV
      Hi friends from Spain.
      Mi new KTM