De-restricting a ZXR400 Import

[speedtrifle]

Hi,

If I want to de-restrict a ZXR400 import, is it just the ignitor box that needs to be changed to increase the max revs from 10,500 to 14,500?

Thanks,
Chris.

[zimm]

they are restricted by a sensor in the speedo that activates a rev limiter at anything over 180kph

remove/unplug the speedo (includes fitting mph clocks)and it restricts it to 10,500 ish rpm

if still fitted with original kph clocks you can fit a kph - mph converter, and leave the clock plugged in to the loom your bike wont do 180mph, so the restriction never cuts in ..

if fitted with an mph clock, you need a UK spec cdi this is part number 21119-1332 M

or a (hard to get hold of) Mmax de-restrictor which plugs in where the kph clock did, but sends a "speedo present, but reading less than 180kph" signal to the stock cdi.

simplest (cheapest) fix on a stock import is to remove the speedo cable inner but then you dont know how fast you're going.

some L model imports also have smaller carbs, you have to take them off and measure them, the smaller ones work fine, but cost you power at the topend, you need the inlet stubs/carbs and bellmouths to get round this.

[speedtrifle]

Thanks for the detailed info.

Cheers,
Chris.

[zimm]

oh, the 21119-1332 cdi will only work on an L, H's have a different loom and wont spark with an L cdi.. been there, tried that, bought an L loom.. but havent fitted it yet.

if its an H, the kph - mph converter is the simplest way forward.