Anyone have black box mod for 300ex? I'd like to know people's opinions on this mod. Good or bad, and their experiences with it. Thanks.

 

i had one on my old 330ex, all they do is take the rev limiter off

 

Did you like it better than the stock one? I'm worried about blowing my motor. My machine isn't stock so it shouldn't hurt it but it still bothers me. Did you ever open it wide open with the rev limiter off? Thanks.

 

It DOES NOT remove the rev limiter. There is no motor on the planet that can rev infinitely--they will explode!! It does raise the max rpm about 1200 rpm. I had a wb cdi on my 400 and sold it. It only gives a few mph on top end at expense of making the motor scream and making it hard to start in cold weather. I would not buy again--use $120 for new high comp piston or nerf bars.

 

IT DOES REMOVE IT just like I DO on my 400ex,300ex,trx300 and 250 mojave.AND my 400ex's start when it's cold because I mod. the stock box.

 

You mod it yourself? You never had a problem starting in the cold?

 

<< IT DOES REMOVE IT just like I DO on my 400ex,300ex,trx300 and 250 mojave.AND my 400ex's start when it's cold because I mod. the stock box. >>

I was referring to the aftermarket cdi's I have seen. The raise the redline up 1,200 rpms. I wasent calling you a liar---I personally would not own a quad with no rev limiter. Even street bikes have a rev limit. You think a Hayabusa 1300R can go to 30,000 rpms????

 

different cdi's have different rev ceilings - talk to the supplier at an engineering level or a good tech guy. They are usually purpose built with a difference in spark advance as well as rev ceilings for a specific engine application. The limit on your rpm's is not just the cdi, but the engine config. cam duration, compression, exhaust baffling. Many engines with high compression will reach a natural rev limit because of pumping forces involved in compressing the gasses. Others will reach the point where exhaust will not exit because of too much back pressure, and therefore the cylinder cannot fill with a useable air fuel mix. When this happens there is not enough hp to overcome pumping pressures in the cylinder and the engine will stop revving. There is more danger in overrevving a stock motor because of lower compression, and often a heavier rotating mass which allows inertial revving past the redline without a limiter.

 

300exazzkikr,
He's Mickey Dunlap of Four Stroke Tech. I hope he can mod a Black Box, if your paying him $85 to do so. [img]i/expressions/face-icon-small-smile.gif[/img]