I own from new a 03 z400. a couple months ago I started modifying it. CT complete pipe,k-n air box lid,jet and needle kit.the last mod was a rev max 9 adj rev box. with the box on, the bike will not spark with the starter button pressed. when the button is released and engine still spinning the plug fires.it is real HARD to start this way.with the stock box on the bike starts easy (fire on the plug all the time) whats up with the rev box?

is their a fix? i contacted the company i bought it from and no response. any help would be great.

the bike runs better and longer in each gear with the box installed. i would like to put it back on but the hard starting is a kill joy. HELP !!! thanks coollukewright@aol.com

 

I actually had the same problem. My bike just sat there for a week while me and some friends called everywhere we could. No one could give us a straight answer but the suzuki shop told me to start it with the gas on reserve and then switch it over to on once the bike started. Works just fine that way. I dunno if it will help you or not but give it a try.

 

Its got to be a wiring issue, a work around might be to bump start it, until the wiring is figured out. If you put the original box back on...does it work ok?

 

yes with the stock box on it starts fine.

 

ditch the box its a bad one get a new one i got a rev box and ended up back to a stocker same problem

 

stewbing, have you dynoed your bike? you say 50+ hp to the ground, I have pretty close to the same setup and I know mine is not 50+. What did i do wrong?>