VFR400 speedo / derestricting question

lalaland · Borekit Bruiser Joined: 01 May 2004 Karma :

Hi,

I have just bought a Jap import VFR400 that's retricted to 113mph by Jap law. When you reach this speed two of the cylinders stop firing aparantly and you can't get any more power until you drop below 113mph.

I have heard of ways of removing this, mainly either cutting two wires to the speedo or changing the speedo to MPH from KPH by adding a converter to the cable. This then means that when doing 113mph the restricter doesn't think you are going as fast as 113mph isn't as high up the clock as what ever it's kph equivelant is.

I prefer the second option as I would like to convert my reading to MPH and leave the KPH clocks in place. It's easier and cleaner to just add something rather than chop something and I would like to know my MPH speed instead of KPH. I wouldn't change the clock though, just leave the KPH in place.

Does anyone know if this works?

My VFR is the 400 NC30 1992 import version.

Thanks
(anyone know what the top end is when derestricted?)

Stew · Posted: 15:37 - 10 May 2004 Post subject:

Yes it does work. The restriction only kicks in when the speedo needle reaches 180kmh. With one of these little converters in place the needle never gets round that far (if your NC30 can do 180mph could I have it please) and therefore removes the restriction.
The other way of doing it requires you to open the clocks and either bend or remove the little bit of metal that is on the back of the clocks at the 180kmh mark, afaik you must make sure that you leave the metal bit that is at 0kmh though.

Oh and you should be able to get about 135mph (speedo reading) probably about 130mph real speed.
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lalaland · Borekit Bruiser Joined: 01 May 2004 Karma :

Stew · Posted: 20:57 - 10 May 2004 Post subject:

Bod · Traffic Copper Joined: 18 Mar 2004 Karma :

so instead of looking at the stickers for mph, the kmh becomes mph?

fazed · Korn is my hero! Joined: 21 Apr 2004 Karma :

Bod · Traffic Copper Joined: 18 Mar 2004 Karma :

Stuff it then, I'll do that instead. I was looking out for a MPH speedo for my ZXR400 but may do that instead.
Cheers

lalaland · Borekit Bruiser Joined: 01 May 2004 Karma :

Does anyone know if it passes the MOT with the clocks showing KPH as their scale but actually giving MPH readings?

Bod · Traffic Copper Joined: 18 Mar 2004 Karma :

how wud they notice?

Laura · Playboy Bunny Joined: 28 Jul 2003 Karma :

When a 400 starts doing 180 mph but no I wouldnot have htought this would have been a problem for the mot ask kev.
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lalaland · Borekit Bruiser Joined: 01 May 2004 Karma :

I think I'll just do it anyway, my MOTs not until January anyway and if it's a problem then it won't be hard to uncouple the connector before getting to the MOT station.

carvell · Scuttler Joined: 05 Sep 2003 Karma :

lalaland · Borekit Bruiser Joined: 01 May 2004 Karma :

Not really, just make a note of the KMs that you've done and then add them to the miles when done.

Shouldn't be a problem surely?

jasthabass · L Plate Warrior Joined: 21 Dec 2009 Karma :

Hey Guys n Girls!!

I hadn't found ANY images on the VFR400 NC30 speed restrictor! (pain in the ass) I looked at the posts and all people would say is "Just bend this or that" but when i opened up the speedo there wasnt anything to bend.

So after a while looking at the insides i ripped this piece of metal out that went in between 2 magnets when the speedo reached 180 to limit the speed of the VFR 400 NC30.

See the photos! Just tested it about 20 mins ago and the needle goes deep into blank space!

Word of advice! (be careful with the speedo needle (the one that points at your speed) it breaks VERY easily!!!

https://www.unitedwebsitedesign.com.au/images/nc30-speed-restrictor.jpg

stinkwheel · Bovine Proctologist Joined: 12 Jul 2004 Karma :

You can also bypass the restriction by attaching a resistor between two of the wires on the CDI.

I did work this out with someone a while back for his track bike but the thread must have been removed in one of the forum clear outs.
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