I purchased one of those WhiteBrothers CDI boxes off Ebay. Ever since I put it on I foul plugs and my 03 400ex won't start when it's cold and when I was looking in the new dirtwheels the CDI box that was going on the quad in the mag looked nothing like the one I have the one I have looks stock but has a WB on the back in the corner. The one in the mag was all nice looking and had WhiteBrothers sticker on it. I only payed I think 65.00 for mine and the ones I see are 150.00 and above. I was talking with a guy at SandLake he purchased the same one and his buddy told him to put a 1" hole in the top of the air box lid thats supposed to help. I thought about instead I got the motoforce airbox lid. I just orderd it last week so I don't have it yet has anyone else heard about these revboxes like the one I got any info would be helpful. It came in a WhiteBrothers box with decals and all. Mabey they have a couple different stages of rev boxes I don't know if anyone has heard of similar problems please help. Pretty much every part on my quad is matched from WhiteBrothers so its all meant too run together. I don't want a bum part messing up the smooth sweetness of my baby ya know what I mean. Thanks

 

Sandrider, I have the same problem with my rev limiter. Recently I found out that the aftermarket rev limiters can be picky, needing a full battery charge. I started running my stock cdi under 50 degrees, and it cleared up my troubles. Fortunately, it is not too hard to replace.

Good luck, MTJEX

 

I hate the be the barer of possible bad news, but it sounds as if someone might have stuck a stock cdi in your ebay purchase right after they peeled the new shiny sticker off the actual white brothers cdi they just bought. I would give White Brothers a call and ask if they even have a cdi that looks remotely like stock. Better yet, ask em to e-mail you a pic of it. Let them know what's going on and see if you can get more info.

I hope I am wrong.

Later.

 

Hey thanks alot I'am gonna do that I actually puchase alot of WhiteBrothers products so I purchased a dealers catalog. I'am gonna check into it thanks.

 

Goodluck.

www.albaaction.com

You can get one from Alba for $99. They also have the white brothers rev box on their site.

 

I bought a brand new one 3 years ago. It is a little shorter than the stock one but has WB in one corner. It came brand new from White Bros. so I don't think you got scammed.

When it is cold out I don't use it and right now I couldn't say where it is. I'll find it in the spring.

 

So it does have a WB carved into the corner of the box so I didn't get scammed that would be great how much did you pay for yours. It seems to make a difference . but have you had problems starting it have you heard of anything to do with a 1" hole in your airbox might help with the starting problem.

 

I paid $105 for it I think. They do give more over-rev but, if your engine is stock you will probably never realize the difference. I have a mid to high rev cam and still don't think I need the WB box. I do run it in the dunes but thats about it.

I dont run my air box lid so holes I've never tried. It is real hard to start when cold, but what you can do is warm it up on the stock box then plug in the other one. It is even harder to start now becaue the FCR 39 carb doesn't have a choke.

 

Hey just got my 400ex going again poped off the WB CDI changed the plug that was extemly fouled and she fired right up like a raging beast. Does your 400ex foul plugs alot mine is damn near new and it fouls plugs left and right I don't know what can be causing this but it is running okay I do notice a difference in the boxes that extra grand makes a diffrernce ecspecialy in the sand. so I guess a guy should only run the WB box in the summer