How do i remove the restrictors

ernie · Post by **ernie** » Thu Sep 28, 2006 10:39 pm

Hi, new to this site and new to the ZXR400 fun machine thats sitting in the shed with the wireing burnt out under the rear shock (giraffe) just bought it
Any hoo!!

I was told it had been restricted but had been removed, propable bullshit as it runs like a bag of poo but I'd thought I'd ask and have a look

Any help

Thanks guys

great site

Post by **dynamatiz** » Thu Sep 28, 2006 10:46 pm

welcome mate

does it get over 115mph or 10k rpm ???

i ve just had a bout with de restrictors too, as far as i know there is a possilbe 3 that it could be(and this is probably all i know lol)

1. one inside the speedo( theres a article on removing it on this site mate)
2. cdi/ecu the little black box that is under the rider seat
3. couple of washers inside the carbs/downpipes

now am not sure which one yours could be cos a still havent found mine out yet, but am sure someone on the board will be able to help you out mate because there full of knowledge on zxr400's

hope this helps

Post by **masterofinsanity** » Fri Sep 29, 2006 1:09 pm

1 thing i've never come across on this forum is if your bike has been restricted in the carbs do they adjust jetting to allow for the decrease in air/fuel flow? or is it the same mixture just less getting through??

Post by **dynamatiz** » Fri Sep 29, 2006 2:21 pm

to be honest mate a havent got a clue, its just what a heard on one of the threads one here am probably mistaken like

icklelea · Post by **icklelea** » Fri Sep 29, 2006 6:36 pm

Id presume they adjust for it cos my bike went mad when i took mine out!!!

mongo · Post by **mongo** » Fri Sep 29, 2006 8:08 pm

They just shove the restrictors between the carb inlet rubbers and the inlet on the engine itself (if its the 33bhp restrictiors).

No re-jetting is done, sometimes you can see the petrol sitting on the restrictor plates as its at an angle.

If you want to check, take the tank off then the airbox, open the throttle wide open and lookdown, if you can see something blocking it with a small hole in the middle, the restrictors are still fitted.

With these restrictors fitted there is no rev limit or top speed restriction (although it will take forever to accelerate past 120).

masterofinsanity wrote:1 thing i've never come across on this forum is if your bike has been restricted in the carbs do they adjust jetting to allow for the decrease in air/fuel flow? or is it the same mixture just less getting through??

Post by **masterofinsanity** » Fri Sep 29, 2006 11:50 pm

but then if the same amount of fuel is getting through there must be excess fuel sitting around the restrictor plates which will flood the plugs ???

mongo · Post by **mongo** » Sat Sep 30, 2006 3:25 pm

Nah theres not that much fuel, only occasionally will you see some on the restrictor plates.

masterofinsanity wrote:but then if the same amount of fuel is getting through there must be excess fuel sitting around the restrictor plates which will flood the plugs ???

Post by **deviant** » Mon Oct 02, 2006 7:50 pm

masterofinsanity wrote:but then if the same amount of fuel is getting through there must be excess fuel sitting around the restrictor plates which will flood the plugs ???

if that happened, it would happen every time you ran on part throttle. the restrictor plates do exactly the same thing as a part open throttle.

if the carbs are properly adjusted, they should put the right amount of fuel in for the amount of air that is going through.

or that's what I think anyway...