Vfr400 nc30 restriction

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Romney1
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Vfr400 nc30 restriction

Post by Romney1 » Tue Jan 23, 2018 11:07 pm

Can someone advise me iv seen people selling there nc30 saying its the full hp modle and un restricked ecu .

How can i tell if mine is full power ? Cheers

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NGneer
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Re: Vfr400 nc30 restriction

Post by NGneer » Wed Jan 24, 2018 11:12 am

Some bikes had their power output restricted to (allegedly) 33HP,through the use of a restriction washer in each of the rubber sections between the carbs and cylinder inlet. These can be easily removed thus returning the bike to is full 59HP.

However in addition, due to most of the 400's coming from the Japanese market, 400 cc motorcycles were once restricted by top speed. The VFR was restricted by means of an optical sensor inside the speedometer, and a black sector attached to the indicator needle shaft. When needle swings round to 180 km/h (110 mph) the sector starts to block the sensor, ignition is cut to the front two cylinders, the effect is similar to hitting a rev-limiter, thereby reducing power such that the motorcycle can not accelerate further.

There are a number of ways to remove this 180KMH speed limitation such as a plug in de-restrictor box, Wiring a resistor in line, fitting an aftermarket (or HRC) ECU. Whichever way you choose, once done it should allow a well sorted bike to carry on to circa 130MPH.......obviously only ever done on the track or on the German autobahns :whistle:

Romney1
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Re: Vfr400 nc30 restriction

Post by Romney1 » Wed Jan 24, 2018 3:06 pm

Thanks for the information my bike is a mix of uk and jap bike so not sure on the wiring loom side the ecu is completely black no markings or stickers and i have another ecu box with a lightning bolt symbol on ,in the box of spares i have . the speedo head is the uk version not just a face change job . There are no inlet washers and also suspect the head Is ported / polished as the uk engine inlets are smaller with a rough finish where my bike are larger and smoother faced . I cant get my head around why the uk engine has been removed as it turns over and looks good but i didnt fancy swapping it to find out why possibly gear box related !i suspect the jap 1992 engine have been tuned im just keeping hold of the engine to give the next owner incase they decide to return it to all uk .

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Re: Vfr400 nc30 restriction

Post by Neosophist » Wed Jan 31, 2018 11:12 am

ecu could be a chinese copy job.. some of these besides the lack of speedo restriction circuit also have no rev limiter so make it very easy to overrev the bike which can result in a lot of engine damage...
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...


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