DERESTRICTING 400H

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richyrd5
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Joined: Fri Feb 05, 2016 12:26 pm
My Bike: 400h

DERESTRICTING 400H

Post by richyrd5 »

Hi.need some advice on derestricting my 400h...its got kmh clocks and red A label cdi...what needs to be done if I put a blue M uk cdi and mph clocks on..is it just plug and play??..any advice helpful as I've read through topics on here but didn't really get a definitive answer. :smt017..
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banner001
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Re: DERESTRICTING 400H

Post by banner001 »

you cant use a M box as thats L only, you need to read rob's posts on derestricting, as far as i know it involves a 1W 10kOhm resistor on the pink wire from the clocks to the CDi? viewtopic.php?f=1&t=7393&st=0&sk=t&sd=a ... r&start=15

if you want to use a M spec CDI you will need to change the rotor pickup to the L varient, and ensure that you wire in the H loom to the L model CDi...not impossible, but you will need to make the connections yourself.

there are colour versions of the L and H looms on the site for you to use.
UK ZXR400 L3 (1993) - Fully restored and on the roads, my green beast!
JPN ZXR250 A2 (1990) - Revs to 19,200rpm... 'nuff said :smt003
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banner001
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Re: DERESTRICTING 400H

Post by banner001 »

or you can use a speedo changing thig thas a series of gears that changes the revolutions of your speedometer cable down by a factor of 1.6...that way your kph clocks now read a true mph instead and thats no mods needed on the electrical side.

you cant use mph clocks from a uk bike unless you use a L loom and L cdi otherwise your bike will be restricted to 10k rpm (from what i remember as the H loom and CDi will read it as a cut pink wire).
UK ZXR400 L3 (1993) - Fully restored and on the roads, my green beast!
JPN ZXR250 A2 (1990) - Revs to 19,200rpm... 'nuff said :smt003
richyrd5
Posts: 63
Joined: Fri Feb 05, 2016 12:26 pm
My Bike: 400h

Re: DERESTRICTING 400H

Post by richyrd5 »

Ah.thats excellent cheers banner...that makes things a lot clearer..think i will go for the resistor mod as the clocks are £50 and £30 for igniter..and cant be arsed swapping pickups/looms/chopping wires.etc...cheers biggrin
richyrd5
Posts: 63
Joined: Fri Feb 05, 2016 12:26 pm
My Bike: 400h

Re: DERESTRICTING 400H

Post by richyrd5 »

But...what does the converter do to overcome the electronic restriction in the speedo cable....if I can get a cable converter won't it still be restricted to 10000 revs??
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banner001
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Re: DERESTRICTING 400H

Post by banner001 »

if you put in the resistor the bike doesnt know that you have gone over 180kph as it sees no change in the resistance on the pink wire...

if you mod the speedo drive then as you will never hit 180MPH (aka what the clock sees as 180KPH) you will never hit the restrictor, so you can leave your loom uncut...

your bike is restricted to 10k rpm if you cut the pink wire entirely (from what i remember - ive only ever worked on L bikes), i.e. if you swap to mph clocks as the ignitor cant see a signal at all...this means you need to keep the kph clocks at all times, unless you swap the loom/cdi/fusebox/pulsar for the L bike.
UK ZXR400 L3 (1993) - Fully restored and on the roads, my green beast!
JPN ZXR250 A2 (1990) - Revs to 19,200rpm... 'nuff said :smt003
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banner001
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Re: DERESTRICTING 400H

Post by banner001 »

i cant vouch for it as ive never needed to use one, but this is like what you want:
http://geargremlin.com/products/bike_ma ... _gg401.php

then your kph clocks become mph, you will never go over 180 so you will be on full power, and as you are keeping your kph clocks/pink wire unmolested you wont be limited to 10k rpm
UK ZXR400 L3 (1993) - Fully restored and on the roads, my green beast!
JPN ZXR250 A2 (1990) - Revs to 19,200rpm... 'nuff said :smt003
richyrd5
Posts: 63
Joined: Fri Feb 05, 2016 12:26 pm
My Bike: 400h

Re: DERESTRICTING 400H

Post by richyrd5 »

:smt003 .excellent.thanks chap....sorted
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