NC30 / NC35 Derestriction and 5000RPM misfire

[fastdruid]

Maybe one for a mod to make sticky as these questions keep poping up?

The 'home market' NC30 and NC35 are restricted to 180Km/h (~112mph) due to laws in force in Japan at the time. UK spec NC30 models are not restricted.

The restriction is in the CDI and is triggered by a rotating disc in the back of the speedo that triggers when the needle reaches 180Km/h, disconnecting this results in the bike only running on two cylinders (misfiring) over 5000RPM.

There are eight ways to derestrict.
1) M-Max, HRC or similar de-restrictor. Small box, plugs inline between the speedo sensor and the wiring loom on NC35, in inline between CDI and wiring loom on NC30.
2) Bent tab in the speedo. Essentially you open up the speedo and prevent the disc from triggering the restriction.
3) Remove restriction from speedo. Remove the circuit board from the speedo but leave it connected (wrapped up in something waterproof!)
4) Use a kmh=>mph converter. You'll never reach 180mph so the restriction doesn't cut in.
5) Disconnect the speedo. Only a temporary measure but ideal for a trackday for example.
6) Add a resistor. Add a resistor (2k2) between two wires either at the speedo or CDI end. (I'll edit this later to provide details of which wires).
7) Short two wires. Connect a wire between the same wires as for adding the resistor. While this works it is suggested you add the resistor.
8) Aftermarket ECU. HRC, Ignitech doesn't matter they lose the restriction.

Druid

[Cammo]

Good stuff Druid.

On the nc30 the off the shelf boxes (m-max, hrc etc) plug in between the cdi and cdi connector.

[white wings]

What ever happened to this thread?!!!!!

DOn't you guys like to post pics of the work done, more like a step by step on the proccess?
Kurt

[wullvfr]

well done druid,keeping everyone happy!!!!!

just need to keep a note of it



william

[1990nc30]

I fitted a speedo converter a while back to try and go past 120mph (i know it's meant to be 112mph but mines cuts out at 120) and with the converter fitted it still doesn't go past 120? It just cuts out and you have to ease the throttle back off a bit to keep going!?
Does anyone know were my bike is restricted? I wouldn't of thought it's 33bhp, i was told it was 60bhp but had no proof. Please help!!!

[wullvfr]

that's a little strange,obviously the restriction works when the needle hit's 180kph triggering the switch and with the converter fitted the needle should never reach 180 as this would now be 180mph...............

i don't think it is because of a 33bhp restriction because the bike would not reach full speed or the speed you are sayng(120mph)...i think that is down to speedo error,mines cuts out at 116mph according to twat nav.



william

[1990nc30]

It is strange, bloody anoying too! Oh well getting a b1h soon! what do you mean speedo error?

[wullvfr]

when your sppedo say's your doing 100mph but you are really doing say 95mph etc.

i think to be honest though my needle passes the 180kph mark before the miss-fire kicks in,what about yours?




william

[1990nc30]

It must do because it says i'm doing 120mph and 180kph is 112mph init, now the converters in it obviously doesn't go anywere near the 180kph (i wish )

[wullvfr]

so the needle is at 120kph with the converter fitted!!!!!! a bit fucked up that!!!!!

before the converter was fitted did the needle go way past the 180kph before mis-firing?or did it work on the 180kph?



william